Weigh Less, Live Longer: Strategies for successful weight loss

| September 1, 2006

Weigh Less, Live Longer: Strategies for successful weight loss

If you've struggled to lose weight, you're certainly in good company. Two of every three Americans are overweight a trend that's prompted us to spend about $50 billion on weight-loss products and services each year. More worrisome is the growing number of people whose weight is endangering their health. Since 1980, the prevalence of adults who have obesity* has doubled, from about 15% to 30%. Excess weight raises the risk of numerous health problems, including some of the nation's leading killers namely, heart disease, stroke, and certain cancers. In fact, experts fear that the rising obesity rates in today's children may mean the next generation will have a shorter life span than their parents.

Despite the many reports heralding discoveries of genes that cause obesity, most people recognize that environmental and social factors are largely to blame for Americans' expanding girth. Of course, the easy availability of high-calorie foods is part of the problem. Lack of regular exercise, combined with long commutes to largely sedentary jobs, is another. But there's a growing awareness that other factors, such as increased stress and lack of adequate sleep, can wreak havoc with the body's internal balancing system, which can also contribute to weight gain.

This report explores the various reasons people gain weight and what they can do to lose it. Many people have unrealistic expectations about how much weight they need to lose. Losing just small amounts of weight about 10% of your body weight can lead to improvements in your health. The emphasis has shifted more toward trying to eat a healthy diet, rather than trying to become thin. Exercise is important, too. Not only does exercise burn calories both while you're doing it and afterward (by boosting your metabolic rate), it also helps curb your appetite.

This report also provides details on the science behind many popular weight-loss diets, as well as information on programs to help people shed pounds, from organized self-help programs to medically supervised, hospital-based services. You'll learn which weight-loss supplement ingredients to avoid and which you might (cautiously) consider trying. Information on prescription drugs for weight loss is also included, as well as descriptions and illustrations of the two most common surgeries for weight loss. Finally, there's a section on weight-loss maintenance that includes tips on keeping weight off which can be just as challenging as losing weight in the first place.

*When possible, this report follows an emerging trend among medical experts, who prefer to use "person with obesity" instead of "obese person." This change reflects an effort to reduce bias against people who have this condition.

Are you overweight?

Health care providers use body mass index (BMI), an approximate measure of body fat based on a person's height and weight, to determine whether a person's weight falls within a healthy range (see below). Another simple measurement is waist circumference. There are also several methods of estimating the percentage of your weight that is fat, including skin-fold measurement, bioelectric impedance, and underwater weighing.

What's your BMI?

To calculate your BMI, follow these four steps:

Measure your height in inches (without shoes) and your weight in pounds (without clothing).
Multiply your weight by 703.
Divide that number by your height.
Divide again by your height.

http://nhlbisupport.com/bmi You can also use a Web-based calculator at or simply look up your BMI in Table 1. These categories were established after several studies examined the BMIs of millions of people and correlated them with rates of illness and death. The studies showed that the BMI range associated with the lowest rate of illness and death is approximately 1925 in men and 1825 in women, so people with BMIs in this healthiest range are considered to be of normal weight. Higher BMIs are associated with progressively higher rates of illness and death. People with BMIs of 2530 are considered overweight, and those with BMIs of 30 or higher are considered to have obesity. Obesity has been further subdivided into mild (BMI of 3035), moderate (3540), and severe (BMI of 40 and above). Severe obesity is roughly equivalent to being 80 pounds overweight if you are a woman or 100 pounds if you are a man.

If your BMI is lower than 18, you are considered underweight. Underweight people also have higher death rates than people of normal weight do, but many people in this category are underweight because they already have a severe illness, such as cancer, chronic infections, or anorexia.

Table 1: What's your body mass index?
The body mass index (BMI) is an index of weight by height. The definitions of normal, overweight, and obese were established after researchers examined the BMIs of millions of people and correlated them with rates of illness and death. These studies found that the BMI range associated with the lowest rate of illness and death is 1925.
Height	Weight in pounds
4'10"	91	96	100	105	110	115	119	124	129	134	138	143	167	191
4'11"	94	99	104	109	114	119	124	128	133	138	143	148	173	198
5'0"	97	102	107	112	118	123	128	133	138	143	148	153	179	204
5'1"	100	106	111	116	122	127	132	137	143	148	153	158	185	211
5'2"	104	109	115	120	126	131	136	142	147	153	158	164	191	218
5'3"	107	113	118	124	130	135	141	146	152	158	163	169	197	225
5'4"	110	116	122	128	134	140	145	151	157	163	169	174	204	232
5'5"	114	120	126	132	138	144	150	156	162	168	174	180	210	240
5'6"	118	124	130	136	142	148	155	161	167	173	179	186	216	247
5'7"	121	127	134	140	146	153	159	166	172	178	185	191	223	255
5'8"	125	131	138	144	151	158	164	171	177	184	190	197	230	262
5'9"	128	135	142	149	155	162	169	176	182	189	196	203	236	270
5'10"	132	139	146	153	160	167	174	181	188	195	202	209	243	278
5'11"	136	143	150	157	165	172	179	186	193	200	208	215	250	286
6'0"	140	147	154	162	169	177	184	191	199	206	213	221	258	294
6'1"	144	151	159	166	174	182	189	197	204	212	219	227	265	302
6'2"	148	155	163	171	179	186	194	202	210	218	225	233	272	311
6'3"	152	160	168	176	184	192	200	208	216	224	232	240	279	319
6'4"	156	164	172	180	189	197	205	213	221	230	238	246	287	328
BMI	19	20	21	22	23	24	25	26	27	28	29	30	35	40
	NORMAL						OVERWEIGHT					OBESE

What's your body shape?

Your body shape depends largely on where you tend to carry your weight, usually centered on either your waist or your hips and thighs. If you carry fat mainly around the middle of your body (known as "apple-shaped"), you're more likely to develop diabetes and related health problems than if you tend to be heavier around your hips and thighs ("pear-shaped"; see Figure 1). To measure your waist circumference, place a cloth tape measure around your bare abdomen just above your hipbones. Make sure the tape is snug and parallel to the floor. A waist circumference of more than 35 inches for women and more than 40 inches for men indicates a higher than normal risk. (See "Do you have metabolic syndrome?")

Figure 1: Apples and pears

Apples and pears

People who are "apple-shaped," or who store fat in the abdomen rather than the hips, are more prone to diabetes and cardiovascular disease than are those who are "pear-shaped," who tend to store fat in the hips and thighs.

What's your body fat percentage?

You can estimate your body fat percentage by several different methods, but be aware that these tools aren't always accurate and doctors don't consider them useful to guide treatment. In general, these methods tend to be less accurate in people with obesity than in people who are slightly overweight or at a normal weight. But some athletes and people who are trying to tone their bodies while losing weight may find it motivates them to keep tabs on their body fat percentage. Healthy adult men have body fat percentages between 10% and 25%, whereas the range for women is between 18% and 32%. Higher percentages are considered abnormal and consistent with obesity. In children, body fat percentages above 25% in boys and 30% in girls are associated with being overweight.

Skin-fold thickness. A technician or health professional uses calipers, a measuring instrument, to gauge the thickness of a fold of skin on the body at several different sites, such as the upper arms, waist, and thighs. The measurements are entered into a formula to produce an estimate of body fat percentage. This method gives a reasonable estimate, but results often vary when different people take the measurements, making this test not very reliable.

Bioelectric impedance. This test uses a small, harmless electrical current to measure the electrical resistance of the body, based on the principle that lean body mass conducts electricity faster than fat body mass. Special "body fat" scales that use this principle in combination with your height and weight can calculate your body fat percentage. Results can vary with the amount of water in your body and are considered unreliable in people with obesity.

Underwater weighing. This test, based on the principle that fat tissue is less dense than muscle and bone, uses a special bathtub-sized tank to weigh a person underwater. That weight is then compared to the person's weight on land; a formula identifies the percentage of body fat that would account for the difference. Underwater weighing is considered the most accurate method, but it is generally available only at universities and research facilities.

Weight and health

Excess body weight increases your risk for more than 50 different health problems (see Figure 2). These health conditions include the nation's leading causes of death heart disease, stroke, and certain cancers as well as less common ailments such as gout and gallstones.

Figure 2: Medical complications of excess weight

Medical complications of excess weight

Excess weight increases a person's risk of more than 50 different medical conditions that affect all the major systems of the body. One of the most common is type 2 diabetes, which can lead to serious complications in the heart, kidneys, nerves, and eyes.

A Harvard study that combined data from more than 50,000 men (participants in the Health Professionals Follow-up Study) and more than 120,000 women (from the Nurses' Health Study) revealed some sobering statistics about weight and health. The volunteers provided their height and weight, as well as details on their diets, health habits, and medical histories. Researchers tracked the volunteers over more than 10 years, noting the occurrence of illnesses and comparing those developments with each subject's BMI.

Obesity increased the risk of diabetes 20 times and substantially boosted the risk of developing high blood pressure, heart disease, stroke, and gallstones. Among people who were overweight or obese, there was a direct relationship between BMI and risk: the higher the BMI, the higher the likelihood of disease.

Greater weight, shorter life?

Journal of the American Medical Association Because excess weight plays a role in so many common and deadly diseases, overweight and obesity can cut years off your life. A study of more than one million adults showed that the lowest death rates were among men with a BMI of 23.5 to 24.9 and women with a BMI of 22 to 23.4. Severe obesity can lower life expectancy by an estimated 5 to 20 years, according to a 2005 report in the .

American Journal of Cardiology, In addition, several studies have hinted that low-calorie diets can slow the aging process. In one such study, published in 2006 in the researchers compared heart function in people who ate restricted-calorie diets (between 1,400 and 2,000 calories per day) with people who ate typical Western diets (between 2,000 and 3,000 calories daily). They found that the hearts of the people who ate low-calorie diets were more elastic and resembled those of younger individuals.

Sleep apnea: Serious complications that start with snoring

If you snore loudly and temporarily stop breathing many times during the night, waking suddenly with a snort or choke, you probably have sleep apnea, another common disorder that's more prevalent with overweight and obesity. Your bedmate will probably notice these symptoms, while you may not. People with sleep apnea don't realize they've been awakened because they don't become fully conscious, but these awakenings can disrupt sleep. Not only does sleep apnea often lead to daytime sleepiness, it also increases the risk of high blood pressure, heart attack, and stroke.

Health benefits of weight loss

Losing excess weight can make you feel better both physically and emotionally and can help you live a longer, healthier life. Especially encouraging is the fact that you don't have to lose a tremendous amount of weight to become healthier. Even a modest weight loss of 5%10% of your starting weight can lead to significant health benefits.

New England Journal of Medicine One major trial to show the benefits of lifestyle changes (including losing weight and exercising) was the Diabetes Prevention Program, published in the in 2002. It involved more than 3,200 people who were at risk for developing type 2 diabetes. Researchers found that people who lost just 7% of their weight and exercised about 30 minutes a day cut their risk of diabetes by nearly 60%.

Earlier, smaller studies offer additional evidence. In one, people with hypertension who lost a modest 10 pounds over 6 months reduced their systolic blood pressure by 2.8 mm Hg and their diastolic blood pressure by 2.5 mm Hg. These reductions in blood pressure were equivalent to the reductions brought about by treatment with blood pressure medications. Weight loss is so effective that many people with high blood pressure can stop taking blood pressure medicine after they lose weight, for as long as they are able to keep it off.

Why people become overweight

Everyone knows some people who can eat ice cream, cake, and whatever else they want and still not gain weight. At the other extreme are people who seem to gain weight no matter how little they eat. Why? What allows one person to remain thin without effort but demands that another struggle to avoid gaining weight or regaining the pounds he or she has lost previously?

On a very simple level, your weight depends on the number of calories you consume, how many of those calories you store, and how many you burn up (see "The calorie equation"). But each of these factors is influenced by a combination of genes and environment. Both can affect your physiology (such as how fast you burn calories) as well as your behavior (the types of foods you choose to eat, for instance). The interplay between all these factors begins at the moment of your conception and continues throughout your life.

The calorie equation

The balance of calories stored and burned depends on your genetic makeup, your level of physical activity, and your resting energy expenditure (the number of calories your body burns while at rest). If you consistently burn all of the calories that you consume in the course of a day, you will maintain your weight. If you consume more energy (calories) than you expend, you will gain weight.

Excess calories are stored throughout your body as fat. Your body stores this fat within specialized fat cells (adipose tissue) either by enlarging fat cells, which are always present in the body, or by creating more of them. If you decrease your food intake and consume fewer calories than you burn up, or if you exercise more and burn up more calories, your body will reduce some of your fat stores. When this happens, fat cells shrink, along with your waistline.

Genetic influences

To date, more than 400 different genes have been implicated in the development of overweight or obesity, although only a handful appear to be major players. Genes contribute to obesity in many ways, by affecting appetite, satiety (the sense of fullness), metabolism, food cravings, body-fat distribution, and the tendency to use eating as a way to cope with stress.

Science A 2006 report in that studied more than 900 people showed that those who have two copies of a specific gene variant (called Insig-2) were 22% more likely to have a BMI higher than 30. Researchers believe the gene variant affects the regulation of another gene involved in fat production. In follow-up studies of more than 9,000 people (including people with Western European ancestry, African Americans, and children), they found that about 10% carried two copies of the gene variant.

Proceedings of the National Academy of Sciences, In another 2006 study, published in the researchers studied the activity levels of three different genes in fat samples from people who were normal weight, overweight, or obese. They took fat samples from around the participants' internal organs and under their skin and found different levels of activity (known as gene expression) in the different samples. In overweight people, increased expression of two of the genes correlated with a tendency to be "apple-shaped." These and related studies have helped researchers better understand how and why obesity occurs. They may also spur the development of new weight-loss treatments.

The strength of the genetic influence on weight disorders varies quite a bit from person to person. Research suggests that for some people, genes account for just 25% of the predisposition to be overweight, while for others the genetic influence is as high as 70% to 80%. Having a rough idea of how large a role genes play in your weight may be helpful in terms of treating your weight problems (see "How much of your weight depends on your genes?").

How much of your weight depends on your genes?

Genes are probably a significant contributor to your obesity if you have most or all of the following characteristics:

You have been overweight for much of your life.
One or both of your parents or several other blood relatives are significantly overweight. If both of your parents have obesity, your likelihood of developing obesity is as high as 80%.
You can't lose weight even when you increase your physical activity and stick to a low-calorie diet for many months.

Genes are probably a lower contributor for you if you have most or all of the following characteristics:

You are strongly influenced by the availability of food.
You are moderately overweight, but you can lose weight when you follow a reasonable diet and exercise program.
You regain lost weight during the holiday season, after changing your eating or exercise habits, or at times when you experience psychological or social problems.

These circumstances suggest that you have a genetic predisposition to be heavy, but it's not so great that you can't overcome it with some effort.

At the other end of the spectrum, you can assume that your genetic predisposition to obesity is modest if your weight is normal and doesn't increase even when you regularly indulge in high-calorie foods and rarely exercise.

People with only a moderate genetic predisposition to be overweight have a good chance of losing weight on their own by eating fewer calories and getting more vigorous exercise more often. These people are more likely to be able to maintain this lower weight.

What are thrifty genes?

When the prey escaped or the crops failed, how did our ancestors survive? Those who could store body fat to live off during the lean times lived, and those who couldn't, perished. This evolutionary adaptation explains why most modern humans about 85% of us carry so-called thrifty genes, which help us conserve energy and store fat. Today, of course, these thrifty genes are a curse rather than a blessing. Not only is food readily available to us nearly around the clock, we don't even have to hunt or harvest it!

In contrast, people with a strong genetic predisposition to obesity may not be able to lose weight with the usual forms of diet and exercise therapy. Even if they lose weight, they are less likely to maintain the weight loss. For people with a very strong genetic predisposition, sheer willpower is ineffective in counteracting their tendency to be overweight. Typically, these people can maintain weight loss only under a doctor's guidance. They are also the most likely to require weight-loss drugs or surgery.

The prevalence of obesity among adults in the United States has been rising since the 1970s (see Figure 3). Genes alone cannot possibly explain such a rapid rise. Although the genetic predisposition to be overweight varies widely from person to person, the rise in body mass index appears to be nearly universal, cutting across all demographic groups. These findings underscore the importance of changes in our environment that contribute to the epidemic of overweight and obesity.

Figure 3: Trends in adult weight

Trends in adult weight

Percent of adults ages 2074* who were at a healthy weight, overweight, or obese

*Data are age-adjusted to the 2000 U.S. standard population.

Healthy weight, body mass index (BMI) = 18.524; overweight, BMI = 2529; obese, BMI ?30.

Cancer Trends Progress Report Sources: National Health and Nutrition Examination Survey (National Center for Health Statistics); 2005 Update (National Cancer Institute, 2005).

Environmental influences

Genetic factors are the forces inside you that help you gain weight and stay overweight; environmental factors are the outside forces that contribute to these problems. They encompass anything in our environment that makes us more likely to eat too much or exercise too little. Taken together, experts think that environmental factors are the driving force for the dramatic increase in obesity.

Environmental influences come into play very early, even before you're born. Researchers sometimes call these in-utero exposures "fetal programming." Babies of mothers who smoked during pregnancy are more likely to become overweight than those whose mothers didn't smoke. The same is true for babies born to mothers who had diabetes. Researchers believe these conditions may somehow alter the growing baby's metabolism in ways that show up later in life.

After birth, babies who are breast-fed for more than three months are less likely to have obesity as adolescents compared with infants who are breast-fed for less than three months.

Childhood habits often stick with people for the rest of their lives. Kids who drink sugary sodas and eat high-calorie, processed foods develop a taste for these products and continue eating them as adults, which tends to promote weight gain. Likewise, kids who watch television and play video games instead of being active may be programming themselves for a sedentary future (see "The trouble with TV: Sedentary snacking").

Many features of modern life promote weight gain. In short, today's "obesogenic" environment encourages us to eat more and exercise less. And there's growing evidence that broader aspects of the way we live such as how much we sleep, our stress levels, and other psychological factors can affect weight as well.

Other causes of obesity

Clearly, our responses to today's obesity-promoting environment, in tandem with genetic influences, are the most significant causes of overweight and obesity. But in some people, drug side effects, illnesses, and genetic disorders can also play a role.

When to see a doctor

Not everyone needs to see a doctor in order to lose weight, but some people might want to consider this route for two reasons. The first is to get professional guidance. If you haven't been able to lose weight on your own by dieting and exercising, your doctor may be able to help by making specific recommendations. The second reason to see a doctor is to be evaluated for health complications that might be associated with your excess weight. It's important to have a medical evaluation if you are over 40, or if you are younger and have any health problems. Such an assessment can provide you with added motivation to lose weight to help lower your blood pressure; to reduce your risk of developing heart disease, diabetes, or cancer; or to live a longer, healthier life.

Chances are, your primary care physician can perform this evaluation. Depending on what the doctor finds, he or she may refer you to a nutritionist or dietitian to assess your eating habits, or to a therapist to address any psychological issues that may be interfering with your ability to attain a healthy weight. If you have obesity or if you are overweight and have obesity-related conditions your doctor may refer you to a medical group that specializes in weight loss or to a hospital-based weight-loss center.

Medical evaluation for weight loss

Whether you start by seeing your own doctor or a weight-loss specialist, the evaluation will begin with your complete medical history. The doctor will ask you how long you've been overweight. This is an important question because it narrows down the possible causes of your excess weight as well as the effective treatments. If you have been overweight since childhood, you probably have a strong genetic predisposition to be overweight. A lifelong weight problem is usually harder to treat without drugs or surgery than one that developed in adulthood. On the other hand, if you've gained weight recently, a program of dieting, exercise, and behavior modification may be enough to help you lose weight and keep it off.

The doctor will also want to know what you have done on your own to lose weight. What diets have you tried? Did you lose weight on any of these plans? How long did you keep off the weight, and how much did you regain? This information can help your doctor determine strategies that might be more successful.

In addition to your personal history, the doctor will ask you about your family history. Are your biological parents overweight? Does obesity run in at least part of your family? If so, the chances are that genetics plays a large part in your problem. Do you have a family history of disorders that can be caused by obesity, such as type 2 diabetes, high blood pressure, or breast cancer? If so, you, too, are at high risk for these problems. In particular, you will be at higher risk for such conditions than if you were overweight but had no family history of them. Such information can also suggest whether you might need aggressive weight-loss treatments, such as medication or surgery.

As part of your medical history, the doctor will need to know the names of all the medications you have been taking. Several drugs can cause weight gain, increase appetite, or interfere with weight-loss efforts. If your weight gain came on soon after you began taking one of these drugs, it may be the cause of your problem. Depending on your condition, you may not be able to stop taking the drug. But if you can substitute or add another drug, you might be able to lose the extra weight.

Other important information concerns symptoms, both physical and emotional. Do you have any symptoms of obesity-related conditions such as heart disease, stroke, hypertension, or type 2 diabetes? Do you have mood swings or other symptoms of depression, such as insomnia? If so, you may need additional tests to evaluate and diagnose these problems. If you appear to have depression, anxiety, or an eating disorder, your doctor may refer you to a psychologist or psychiatrist.

Screening tests

After the medical history, you will need a physical examination and certain screening tests. Part of the physical exam is to measure your height and weight accurately in order to determine your BMI, which indicates the severity of your weight problem. The doctor may also measure the circumference of your waist and hips (see "What's your body shape?").

Even if you are only mildly overweight, abdominal obesity increases your risk for type 2 diabetes, heart disease, and stroke. Excess fat around the abdomen helps make the body resistant to insulin, the hormone that enables blood sugar to enter the cells where it can be used as fuel. When insulin doesn't act effectively, the pancreas secretes more of it; excess insulin increases blood pressure and triglycerides and lowers the level of HDL ("good") cholesterol.

The doctor will also take your blood pressure to check for hypertension and will draw blood to check for other problems, such as high levels of cholesterol, triglycerides, and glucose. High levels of LDL ("bad") cholesterol and triglycerides are risk factors for heart disease. An abnormally high level of glucose is a sign of type 2 diabetes. Finally, if the doctor suspects a hormonal abnormality, such as hypothyroidism or adrenal gland hyperactivity, he or she will test your levels of thyroid-stimulating hormone and cortisol.

Designing a treatment program

If you have a health problem related to being overweight, the doctor will recommend a treatment for that condition. You may need medication for high blood pressure, high cholesterol, type 2 diabetes, or other complications. If you have depression, your doctor may recommend an antidepressant, psychotherapy, or both before you start a weight-loss program. But treating the health problems associated with overweight cannot help you lose weight. You will need a weight-loss plan not only to reduce your weight, but also to aid in the treatment of any obesity-related problems.

The plan that your doctor recommends will depend on several factors, including your BMI, whether you have obesity-related health problems, and the degree of your past success in losing weight. If you are mildly overweight and in relatively good health, your doctor may be able to provide guidance on diet and exercise having you come in for regular office visits to monitor your progress and helping you overcome the common weight-loss plateaus. Or your doctor may recommend weight-loss programs offered locally by self-help organizations, companies, registered dietitians, or hospitals. You can find a registered dietitian in your area by calling the American Dietetic Association (see "Resources").

But in some cases for example, if you are extremely overweight or if you have obesity-related health problems and haven't been able to control your weight on your own a weight-loss program that involves dieting, exercise, and social support may not be enough. In such cases, your doctor will probably refer you to a weight-disorders specialist or to a hospital-based weight-loss program to consider whether one or more of the medical options, such as a very low-calorie diet, weight-loss medication, or bariatric surgery (see "Weight-loss surgery"), might be appropriate for you.

In discussing the various weight-loss options, your doctor may ask you about your goals and expectations: How much weight do you expect to lose? How much of an improvement in health and emotional well-being do you expect this weight loss to provide? The purpose of these questions is to find out how realistic your expectations are. Don't be surprised or get discouraged if your doctor tells you to set more modest goals. Your doctor will help you set realistic goals about how much weight you need to lose, how much you can expect to lose, and how much you can expect to keep off in the long run that is, for a year or more.

Such considerations are important because many overweight people begin a weight-loss program expecting to shed many more pounds than will be possible for them. In one study of women with obesity in a weight-loss program, the women said that they wanted to reduce their weight by 32%. That's significantly more than even the best weight-loss programs achieve with weight-loss drugs and diets. Most people who go through weight-loss programs lose 5%10% of their initial weight. Moreover, the National Institutes of Health (NIH) now defines a successful weight-loss effort as one in which a person loses and keeps off 10% or more of his or her initial weight.

How to lose weight

Eat less, exercise more. If only it were that simple! As most dieters know, losing weight can be very challenging. As we've seen, a range of influences can affect how people gain and lose weight. But a basic understanding of how to tip your energy balance in favor of weight loss (see Figure 5) is a good place to start.

Figure 5: A balancing act

A balancing act

To lose weight, you must take in less energy (fewer calories) through food than you expend through exercise and metabolism. Some diets may succeed (in the short term, at least) simply because they lead to a reduced calorie intake even if their methods are not explicitly grounded in calorie reduction.

Counting calories: Doing the math

Start by determining how many calories you should consume each day. To do so, you need to know how many calories you need to maintain your current weight. Doing this requires a few simple calculations.

First, multiply your current weight by 15 that's roughly the number of calories per pound of body weight needed to maintain your current weight if you are moderately active. Moderately active means getting at least 30 minutes of physical activity a day in the form of exercise (walking at a brisk pace, climbing stairs, or active gardening). Let's say you're a woman who is 5 feet, 2 inches tall and weighs 150 pounds, and you need to lose about 12 pounds to put you in a healthy weight range. If you multiply 150 by 15, you will get 2,250, which is the number of calories per day that you need in order to maintain your current weight (weight-maintenance calories). To lose weight, you will need to get below that total.

For example, to lose 1 to 2 pounds a week a rate that experts consider safe your food consumption should provide 5001,000 calories less than your total weight-maintenance calories. If you need 2,250 calories a day to maintain your current weight, reduce your daily calories to 1,2501,750. If you are sedentary, you will also need to build more activity into your day. In order to lose at least a pound a week, try to do at least 30 minutes of physical activity on most days, and reduce your daily calorie intake by at least 500 calories. However, calorie intake should not fall below 1,200 a day in women or 1,500 a day in men, except under the supervision of a health professional. Eating too few calories can endanger your health by depriving you of needed nutrients.

Calories from drinks
Beverage	Amount	Calories
Lemonade	8 ounces	60
White wine	4 ounces	100
Beer	12 ounces	150
Cola	12 ounces	154
Gin and tonic	8 ounces	171

Meeting your calorie target

How can you meet your daily calorie target? One approach probably the most accurate is to add up the number of calories per serving of all the foods that you eat, and then plan your menus accordingly. You can buy books that list calories per serving for many foods. In addition, the nutrition labels on all packaged foods and beverages provide calories per serving information. Make a point of reading the labels of the foods and drinks you use, noting the number of calories and the serving sizes. Many recipes published in cookbooks, newspapers, and magazines provide similar information.

If you hate counting calories, a different approach is to restrict how much and how often you eat, and to eat meals that are low in calories. Indeed, dietary guidelines issued by the American Heart Association stress common sense in choosing your foods rather than focusing strictly on numbers, such as total calories or calories from fat. Whichever method you choose, research shows that a regular eating schedule with meals and snacks planned for certain times each day makes for the most successful approach. The same applies after you have lost weight and want to keep it off. Sticking with an eating schedule increases your chance of maintaining your new weight.

What determines your metabolic rate?

Total metabolism is the rate at which you use energy (measured in calories) when you're exercising or doing anything else (including sleeping). Resting energy expenditure is the rate at which you burn calories when you are not being physically active. Resting energy expenditure varies from person to person and is affected by your age, sex, genetic makeup, psychological state, and level of physical activity. For example, pregnancy and illness both tend to increase resting energy usage. Both total metabolism and resting energy expenditure influence your weight by affecting how many calories you burn in the course of a day.

Some people focus on reducing the fat in their eating plan because, at 9 calories per gram, fat by weight contains more than twice as many calories as carbohydrates or proteins (4 calories per gram). By substituting lean cuts of meat for fatty ones, avoiding high-fat packaged foods and snacks, and refraining from fat-rich products such as butter, mayonnaise, and salad dressings, you can cut out dozens or even hundreds of calories per day. On the other hand, many people mistakenly think that cutting fat always means cutting calories. Some fat-free foods actually contain more calories than the regular versions because manufacturers use extra sugar to make up for the flavor lost in removing the fat. Moreover, low-fat or nonfat foods are not low-calorie if you consume them in large quantities.

Here are some guidelines to follow when straight calorie counting is impractical.

Eat foods that are filling and low in calories. That means meals and snacks made with whole grains, such as brown rice, whole-wheat bread, and oatmeal, as well as legumes, such as lentils and other beans.
When you eat meat, cut out fat and cut down portion sizes. Choose lean cuts of meat and modest amounts about 3½ or 4 ounces per serving.
Avoid fried foods. Frying foods adds fat and calories. For stovetop cooking, it's better either to stir-fry foods in nonstick pans lightly coated with a cooking-oil spray or to braise them in broth or wine. Baking, broiling, and roasting add no extra fat to your meals.
Use low-fat or nonfat dairy foods. Milk, yogurt, and cheese are good sources of protein and calcium, but the whole-milk versions of these dairy products are very high in fat.
Avoid fast foods. Hamburgers, chicken nuggets, French fries, and other fast-food meals and snacks tend to promote weight gain for two reasons. First, they are high in fat, calories, or both. Second, the "value meals" are often excessively large and tempt you to overeat.
Avoid high-fat and high-carbohydrate snacks. Both types of snacks are high in calories. Even snacks labeled "low-fat" are often high in calories because they contain large amounts of sugars and other carbohydrates.
Watch what you drink. Regular sodas, fruit juices, and, especially, alcoholic beverages are high in calories (see "Calories from drinks").
Eat scheduled meals and snacks. It may seem that skipping meals or cutting out snacks is a smart way to cut out calories, but doing either of these things can work against you. You need to eat regularly, even when you're on a diet. If you don't, you'll feel so hungry that you may give up in frustration.

One weight-loss method

If you are moderately overweight but not obese, here's one way to tip the energy balance in your favor.

If you are moderately active:

Multiply your weight by 15 to get the number of calories that you need each day to maintain your weight. For example, if you weigh 200 pounds, 200 15 = 3,000 weight-maintenance calories.
To lose 1 pound each week, you have to consume 500 fewer calories a day. Thus, for the above example, 3,000 500 = 2,500 calories per day.

If you are sedentary:

Follow the steps above, plus
Get 30 minutes of moderate to vigorous activity on most days. Activity of this intensity and duration will burn 150250 calories a day.

Physical activity: How much is enough?

If one person cuts back on calories without exercising and another person increases exercise without cutting back on calories, the first person would lose weight more quickly. That's because it's easier to cut 500 calories a day from your diet than it is to burn 500 extra calories through exercise. You'd have to walk or run about 5 miles a day or 35 miles a week to lose 1 pound of fat. But if you only cut back on calories, you're more likely to regain the weight you lose. Why? The body reacts to weight loss as if it were starving and, in response, slows its metabolism. When your metabolism slows, you burn fewer calories even at rest. When you burn fewer calories, three things can happen. If you continue eating fewer calories, you will either stop losing weight as quickly as you have been, or you'll stop losing weight altogether. If you increase your calorie consumption, you may actually gain weight more quickly than you have in the past. The solution is to increase your physical activity because doing so will counteract the metabolic slowdown caused by reducing calories.

A regular schedule of exercise raises not only your energy expenditure while you are exercising but also your resting energy expenditure that is, the rate at which you burn calories even when the workout is over and you are resting. Resting energy expenditure remains elevated as long as you exercise at least three days a week on a regular basis. Because it accounts for 60%75% of your daily energy expenditure, any increase in resting energy expenditure is extremely important to your weight-loss effort. The kinds of vigorous activity that can stimulate your metabolism include walking briskly for 2 miles or riding a bike uphill.

For people who have obesity and who have been sedentary, any amount of physical activity is beneficial, including walking, swimming, and water aerobics. But start out slowly, and gradually increase the pace and duration of such activities. Low-intensity activities such as taking a short walk or raking leaves won't raise your resting energy expenditure as much as high-intensity activities will, but they have other advantages. For one thing, they help reduce body fat and build muscles and muscle tissue burns more calories than fat does. Regular weight lifting also builds muscle and has a similar effect.

Another benefit of regular physical activity of any sort is that it temporarily curbs your appetite. Of course, many people joke that after a workout they feel extremely hungry and promptly indulge in a snack. But because exercise raises resting energy expenditure, people continue to burn calories at a relatively high rate. So a moderate snack after exercising does not erase the benefits of exercise in helping people control their weight.

Calories burned in each mile of walking or jogging
Body weight (pounds)	Calories
100	67
110	74
120	83
130	89
140	95
150	100
160	108
170	115
180	121
190	128
200	135
210	141
220	148

Starting an exercise program

Many people are daunted by the prospect of starting an exercise program, but it doesn't need to be overwhelming. One approach is to look at your schedule and determine where you can regularly fit in a 30-minute exercise session. For some people, this may mean getting up a half-hour earlier. For others, lunchtime or after work is most convenient. Your goal is to improve your health and lose pounds by doing 30 minutes or more of an activity that's moderately intense, five days a week. If you don't reach this goal at first, it's good to know that any increase in physical activity is better than none.

For some people, a less structured approach may work. You don't have to work out at the gym or participate in a sport, although some people find that these things help them stick to a routine. Many ordinary everyday activities count as moderate-intensity exercise: taking the stairs instead of the elevator, walking instead of driving, cutting the lawn with a push mower, or playing with the children. A significant plus for busy people is that the physical activity doesn't have to be done in a single session. You can break up the 30 minutes for example, by taking a 10-minute walk to the post office and later having a 20-minute bike ride with the kids. Research has shown that breaking up physical activity into 10-minute spurts throughout the day burns up at least as many calories as exercising in a single block of time. Once people get into the habit of setting aside time on most days for physical activity, they tend to be more open to new kinds of activities because they feel stronger and more capable of exerting themselves. People who had never considered taking up a new sport might find themselves wielding tennis racquets, strapping on cross-country skis, or joining a recreational volleyball team. Becoming more active over time helps the effort to keep pounds off.

Exercise prescription

Everyone is different, so there's no such thing as a one-size-fits-all exercise plan. But following this prescription is a good place to start, especially if you haven't yet made exercise part of your daily routine.

Increase the beat. Focus at first on activities or exercises that make the heart and lungs work harder. These include walking, jogging, swimming, cycling, dancing, gardening, playing racquetball, and a host of others.

Make it last. Aim for at least 30 minutes of activity in a day. If you can do it all at once, great. If not, three 10-minute bursts of activity are fine, too. Don't hesitate to go beyond that 30-minute target the longer you are active, the more you benefit.

Do it often. Be active on most days of the week.

It's okay to be moderate. Exercises or activities that are low to moderate in intensity are fine, and are safer for many people. If you like vigorous activity, do it.

Be strong. Add some weight lifting or other resistance exercises to your aerobic activities. Choose weights that let you do 1215 repetitions of exercises that work your arm, leg, shoulder, and hip muscles.

Limber up. Gentle stretches can warm up your muscles before exercise. They can also improve your balance and flexibility.

Behavior modification: Adopting healthier habits

Calorie restriction and exercise help many people lose weight, but only for as long as they keep up the effort. And the same environmental and psychological factors that accounted for the weight gain in the first place can play a role in causing someone to stop exercising or start consuming too many calories. The difficulty in sustaining a diet and exercise routine is one of the main reasons that people who lose weight fail to keep it off. But the difference between long-term success and failure is the ability to make the changes in your diet and activity level permanent.

Certain strategies are useful for everyone who wants to lose weight, regardless of the main causes or severity of their obesity. Many of the following strategies seem like common sense, but they are easily overlooked. You're most likely to follow them if you plan for them in advance.

Eat slowly. Chewing and swallowing your food at a leisurely pace can help you keep from overeating. Here's why: It takes about 20 minutes for your brain to "tell" you when you feel full. Until then, you continue to feel hungry and want to eat. If you eat quickly, you'll end up consuming more than you need to feel full. But eating slowly gives your brain the time it needs to signal that you've had enough.

Make changes gradually. Don't expect to change your diet and activity level overnight. Instead of switching all at once to a low-calorie eating plan, try gradually decreasing the calories of your meals and snacks. For example, start by cutting out snacking or limiting yourself to certain snacks at certain times of day (such as a mid-morning banana or a late-afternoon apple). Also, gradually reduce the calorie content of particular foods. For example, if you're used to drinking whole milk, first switch to milk with 2% fat; then, as you get used to the taste of less fat, go on to milk with 1% fat and finally to skim milk. Another strategy is to lower the calorie content of one meal at a time. In the first week, you might want to eat a low-calorie breakfast, but keep lunch and dinner the same as before. During the second week, you might reduce the calorie content of your lunch. Finally, you can begin eating low-calorie dinners.

Keep a record. Keeping a daily log of what you eat and what physical activities you engage in can help keep you motivated to stay with your diet and exercise plan. Looking over a week's worth of entries can tell you how successful you've been and can help you identify areas where you need to improve.

Seek social support. You'll find it easier to maintain behavioral changes if you have the support and encouragement of others. Social support can come in many forms and from various people. For starters, ask your family members to keep high-calorie foods out of the house, or at least to refrain from eating them in front of you. You might even try to enlist your family to eat the same meals you do. Exercise with someone else, or join a support group. The camaraderie can help keep your spirits up during the inevitable periods when you become discouraged with your progress.

Use a list when buying food. Stick to your grocery list, and steer clear of those aisles or areas with the kinds of calorie-dense foods that you need to avoid.

Out of sight, out of mind. At home, put the most tempting foods high up in the cupboard, at the very back of the fridge, or in other inconvenient spots. Replace the cookie jar and candy bowl with a fruit bowl. Never eat directly out of a large package; many small containers are better than a few large ones, because they provide convenient stopping points. And don't put out too many different varieties of the same kind of food you'll be tempted to sample from each one and eat a lot more than if you were faced with fewer choices.

Don't go all out when eating out. Eat a low-calorie snack before going out; you're less likely to go off your diet if you're feeling full when you get to the party or restaurant. Go elsewhere for after-dinner coffee so you are less tempted to segue right into dessert.

Make a plan for special occasions. Decide how much you're going to eat before an event, and do your best to stick with that plan. Set some limits before you go to the movies or watch the Sunday afternoon football games. It's so easy to mindlessly munch when you're in front of a screen of any kind.

Be a copycat. When eating with a group of people, look around. Who's eating the least? Who has the healthiest food on their plate? Model your eating habits on those people's.

Find physical activities that you enjoy. For example, if you don't like exercising outdoors on cold days, join a fitness club, or get an exercise bicycle and hand weights to use at home. If the problem is a time crunch, exercise in increments of 10 minutes whenever you have the time before work, after work, or during your lunch hour.

Reduce stress. If you overeat when you are under stress, find a stress-reduction method that works for you: meditation, relaxation techniques, listening to music, exercising, or talking to a friend.

Table 2: How to burn about 150 calories

Washing and waxing a car for 4560 minutes

Washing windows or floors for 4560 minutes

Playing volleyball for 45 minutes

Playing touch football for 3045 minutes

Gardening for 3045 minutes

Wheeling self in wheelchair for 3040 minutes

Bicycling 5 miles in 30 minutes

Dancing fast (social) for 30 minutes

Pushing a stroller 1½ miles in 30 minutes

Raking leaves for 30 minutes

Walking 2 miles in 30 minutes (15 min/mile)

Water aerobics for 30 minutes

Swimming laps for 20 minutes

Wheelchair basketball for 20 minutes

Basketball (playing a game) for 1520 minutes

Bicycling 4 miles in 15 minutes

Jumping rope for 15 minutes

Running 1½ miles in 15 minutes (10 min/mile)

Shoveling snow for 15 minutes

Climbing stairs for 15 minutes

Physical Activity and Health: A Report of the Surgeon General, Source: U.S. Department of Health and Human Services, 1996.

Popular diets

The answer to the perennial question "What's the best diet for losing weight?" is any diet that you can stick with for a long time. It should be as good for your overall health your heart, bones, colon, and psyche as it is for your waistline. It should offer plenty of good-tasting and healthy choices, banish few foods, and not require an extensive and expensive list of groceries or supplements.

Many different weight-loss diets have been in the limelight, from very low-fat diets (such as the Ornish and Pritikin diets) to low-carbohydrate diets (such as Atkins and South Beach) as well as combination diets (such as the Zone). Other trends include calorie-density diets (Volumetrics) and Mediterranean-style diets (such as Sonoma).

Here are short summaries of some of the most popular types, followed by a "bottom line" assessment of their effectiveness.

Low carbohydrate

Low fat

Correct carbohydrates

Perfect proportions and careful combinations

Calorie-density diets

Behavior change

Mediterranean style

The diet studies

Journal of the American Medical Association, What do scientists say about how the different diet plans compare? The results of studies often suggest that it's not the diet plan but whether you stick with it that makes the difference. For example, in a 2005 study published in the researchers randomly assigned a group of 160 overweight and obese adults to one of four popular diet plans: the Atkins diet, the Ornish diet, Weight Watchers, and the Zone diet. After one year, nearly half of the participants had dropped out of the study. But those who completed the study lost similar amounts of weight (about 5 to 7 pounds each, on average). They also lowered their blood levels of cholesterol and several other markers linked to heart disease and diabetes to a similar degree. People assigned to the Atkins and Ornish diets were more likely to drop out of the study, suggesting that many people found these plans too extreme. But for certain people, the structure of a restricted plan may be helpful.

British Medical Journal A similar study, published in the in 2006, compared four programs: the Slim-Fast plan (a meal-replacement approach), Weight Watchers, the Atkins diet, and Rosemary Conley's "Eat Yourself Slim" low-fat diet and fitness plan (which includes a weekly group exercise class). All the diets helped people shed pounds and fat, but many more than half of the participants dropped out of the study after eight weeks. About 45% of people in the Rosemary Conley and Atkins groups who completed the six-month study lost 10% of their body weight. For the Weight Watchers and Slim-Fast groups, success rates were slightly lower: only 36% and 21%, respectively, lost 10% of their weight.

Another line of evidence about effective weight-loss strategies comes from a few carefully controlled trials in which volunteers with obesity were blindly assigned to either a standard low-fat diet or a low-carb, high-protein diet. Over all, these trials showed that a low-carb, high-protein diet leads to quicker weight loss than a low-fat diet. In the studies that lasted for a year or longer, though, weight loss was about the same regardless of diet type. These studies focused primarily on weight, and were too short to track other important consequences of diet, such as heart disease, diabetes, bone strength, and cancer.

The overall results mask some startling individual differences. In one trial, on both low-carb and low-fat diets, some people lost weight while others gained. In the low-fat group, the range was from 53 pounds lost to 31 pounds gained. In the low-carb group, it was from 65 pounds lost to 18 gained.

The take-home lesson is that it is okay to experiment on yourself. If you give a diet your best shot and it doesn't work, maybe it wasn't the right one for you, your metabolism, or your situation. Don't get too discouraged or beat yourself up because a diet that "worked for everybody" didn't pay off for you. Try another.

The glycemic index and obesity

The glycemic index is a measure of how quickly the carbohydrate derived from a particular food is absorbed into your bloodstream. Of course, the amount of carbohydrate you eat also affects your blood sugar and insulin levels.

Doctors originally developed the index to help people with diabetes avoid foods that increase blood sugar too quickly, but some experts think it can also help people avoid obesity-related health problems.

The glycemic index ranks foods on a 100-point scale, with 100 being the fastest rate of absorption. Foods with sugars that are absorbed quickly have high glycemic indexes; those with sugars that are absorbed slowly have low glycemic indexes. When sugar is absorbed quickly, it increases the release of insulin, the hormone that transports sugar to the cells for fuel. Spikes in insulin levels, if they occur regularly, may promote insulin resistance, a condition in which the body doesn't respond normally to the hormone. When insulin doesn't function properly, levels of blood sugar and fats rise, increasing the risk for diabetes, coronary heart disease, and possibly stroke, kidney failure, and cancer.

In general, high-carbohydrate foods have the highest glycemic indexes; proteins and fats have glycemic indexes that are close to zero. Proponents of low-carbohydrate diets cite the glycemic index in justifying systematic reductions in carbohydrates. However, most scientists disagree. In cutting back on all foods with relatively high glycemic indexes, you would end up avoiding many healthy foods, including carrots (glycemic index of 71), sweet potatoes (glycemic index of 54), and brown rice (glycemic index of 55).

Some experts argue that people should avoid certain foods that are high on the glycemic index or should eat them only in moderation because they may cause insulin resistance and obesity, although this view remains controversial. The principal suspects are foods heavy in simple sugars, such as candy bars and cookies, and processed carbohydrate foods, such as potato chips, breakfast cereals, and many of the low-fat foods that are on the market. In addition to wreaking havoc with your insulin levels, such foods tend to be high in calories, and excess calories translate to excess pounds.

Glycemic indexes of popular foods
Food	Glycemic index
Yogurt, low-fat with artificial sweetener	14
Milk, whole	27
Kidney beans	27
All-bran cereal	30
Milk, skim	32
Yogurt, low-fat with fruit and sugar	33
Apple	36
Spaghetti, whole wheat	37
Chocolate	49
Rice, white	50
Banana	53
Rice, brown	55
Spaghetti, white	57
Bread, whole wheat	58
Cheese pizza	60
Ice cream	61
Bread, white	72
Corn flakes	77

Weight-loss programs

Each year, millions of Americans enroll in weight-loss programs. These include well-known commercial programs such Weight Watchers and Jenny Craig and organized self-help programs such as Overeaters Anonymous. Fewer people may be familiar with medically supervised programs, which include hospital-based programs or individual care from a physician. Internet-based commercial weight-loss programs have grown in popularity.

The commercial programs charge a fee for meetings. They offer nuts-and-bolts diet and exercise regimens and, in some cases, sell prepared foods and diet aids. The self-help programs tend to focus mainly on providing emotional support and encouragement in sticking with a weight-loss plan. Clinical programs, which are provided through a doctor's office or hospital clinic, offer comprehensive diet, exercise, and behavior-modification programs, supplemented as needed with prescription treatments, such as very low-calorie diets, weight-loss medications, and, increasingly, surgery.

It's important to note that none of the programs can guarantee that you will lose a particular amount of weight. With the exception of the clinical programs, these approaches are adjuncts to, not substitutes for, professional guidance for those who need it. Indeed, the self-help and commercial plans encourage participants to consult with health care professionals about weight-loss strategies. Here is a description of the various categories of weight-loss programs, what you can expect from them, and their relative costs.

Commercial programs

Like self-help programs, the commercial programs hold regular meetings to provide encouragement and support. But a significant difference between the two categories of program is money. The commercial programs charge fees to participate in meetings and also sell diet plans, as well as prepared foods and diet aids to go along with those plans.

Weight Watchers. The most popular of the commercial programs, Weight Watchers, has more than 25 million participants worldwide. The heart of the Weight Watchers program is its points system, which attempts to take the guesswork out of calorie counting. Weight Watchers scientists assigned a point value to various foods based on their calories, fat, and nutrients. When you start, the Weight Watchers staff will tell you, based on your weight, how many points you can eat each day to lose weight. You will also receive literature listing the point values of a wide range of foods. You can eat whatever you like, as long as you don't exceed your daily point total. There's no need to buy Weight Watchersbrand foods. The program encourages members not only to follow the points system, but also to get regular exercise.

Weight Watchers doesn't promise that you will lose a certain amount of weight on its points system. Two published trials showed that people who went to Weight Watchers meetings regularly lost about 5% of their weight over three to six months. Weight Watchers charges about $12 per meeting, although the fee varies slightly by region. Including membership fee, the approximate cost for three months is $167. Meetings are led by people who have successfully lost weight and kept it off through the Weight Watchers program. There is also an online version of the program, which costs about $65 for three months.

Jenny Craig. This is the other leading commercial weight-loss program, and it is only for women. Jenny Craig consists of about 640 weight-loss centers around the world. To get started, you visit a local Jenny Craig center and have your weight analyzed by a staff member. These staff members are not dietitians or other health professionals, but they're trained in the Jenny Craig program, which, according to the company, was developed by dietitians. Based on your weight, the staff member recommends a dieting, exercise, and behavior-modification program to help you lose about 1 pound a week.

In general, members are advised to eat three meals a day and three snacks, as well as to drink eight 8-ounce glasses of water each day and to increase their physical activity as much as they can. Jenny Craig also sells a wide array of packaged foods, diet aids, vitamin and mineral supplements, and even devices. One such device, used by many programs, is a pedometer, a small, pager-sized box you wear that counts the number of steps you take, helping you estimate your activity level. People have the option of preparing their own meals, but the prepared foods have been shown to help them stick with the diet. Adding together the membership fee and meal plan costs, the approximate cost for three months is $1,249.

Internet-based diet plans

These plans are another development in commercial weight-loss programs. Shape Up America!, a nonprofit weight-management organization, provides a list of online programs on its Web site (see "Resources"). Some of the better-known programs include eDiets, NutriSystem, DietWatch, and online programs from Weight Watchers and WebMD.

Obesity Research For example, the eDiets program, which charges $65 for three months, provides subscribers with lists of low-calorie recipes and foods based on the dieter's likes and dislikes. You then choose 1 of more than 20 different diets, for which you buy and make your own food. All the meal plans represent low-calorie diets designed to help you lose about a pound or 2 a week. The company also offers online chats with other subscribers and free e-mail advice from experts, including psychologists and dietitians. However, a 2004 study in compared eDiets with the LEARN (Lifestyle, Exercise, Attitudes, Relationships, and Nutrition) Program for Weight Management, a weight-loss program developed by a Yale University researcher; eDiets users lost just 1.1% of their weight after one year, whereas the LEARN users lost 4%.

Self-help programs

These nonprofit programs have local chapters around the country. They make no promises that they will help you lose any weight. However, they aim to improve your odds of doing so by holding regular (usually weekly) meetings where members share success stories and frustrations and offer one another encouragement and personal tips. Meetings are run by volunteer group leaders. Each self-help program has a different focus.

Overeaters Anonymous. This is a 12-step program modeled after Alcoholics Anonymous for people who suffer from compulsive overeating. The main purpose of the meetings is to help people stop overeating by exploring their underlying emotional issues. Overeaters Anonymous has chapters around the world. It is free, although members are asked to contribute what they can. A special feature of the program is a buddy system in which you have another member to call if you feel the urge to overeat. Whether this approach is appropriate or effective for overeaters remains controversial.

Take Off Pounds Sensibly (TOPS). This program takes a practical approach, giving members incentives to follow whatever diet plan has been recommended by their health care practitioners. One program that TOPS recommends is the "exchange" diet established by the American Dietetic Association and the American Diabetes Association, but TOPS asks that members check with their doctors first.

Upon joining, members record their weight and then compete to see who can lose the most. Winners get rewards. Weekly meetings begin with members weighing themselves (although not necessarily revealing their weight to the group) and then discussing their successes and difficulties in reaching their weight-loss goals. Some chapters arrange for doctors, nutritionists, and other weight-loss experts to speak at meetings. TOPS also holds retreats and rallies to give members extra incentives to stay with their weight-loss plans.

TOPS charges an annual membership of $24, as well as dues. The dues vary from chapter to chapter, but are usually less than $5 per month. Members receive a monthly magazine that contains low-calorie recipes as well as inspirational stories by members who have met their weight-loss goals.

Clinical programs

These programs are run by health care professionals, either in private practice or at hospital-based centers. Many of these programs are staffed by multidisciplinary teams that may include doctors, dietitians, exercise therapists, and psychologists or social workers, who provide a wide range of services, such as nutrition education, medical care, behavioral therapy, and guidance on exercise.

The mainstay of clinical programs used to be a very low-calorie diet of 800 or fewer calories a day, which is at least 400 calories per day less than conventional diets. Very low-calorie diets feature commercially prepared liquid formulas, such as Optifast, that replace all of the food in a patient's diet and induce a rapid loss of about 20% of his or her initial weight over 12 to 16 weeks as much as 5 pounds a week. This type of diet is considered appropriate only for patients with a BMI greater than 30 who need to lose weight quickly and for health reasons. Other clinical programs offered in the United States include Health Management Resources and Medifast/Take Shape for Life.

As part of the program, people on very low-calorie diets should have regular medical checkups to identify any adverse health effects. Patients should also have counseling to help them adjust to the diet, as well as guidance on how to reintroduce regular food once the diet is over. Many programs also offer support groups to help people maintain their weight loss by adhering to a low-calorie diet and getting regular physical exercise. Very low-calorie diet programs usually cost between $1,000 and $2,000 for three months.

Today, however, clinical programs are now inclined to recommend a more moderate low-calorie diet in conjunction with a program of exercise and behavior modification. For one thing, very low-calorie diets have been associated with complications in some people, including chemical abnormalities and irregular heartbeats. And in the long run, such diets are no more effective than conventional low-calorie diets in which people consume about 1,200 calories daily. For patients with obesity and for those who are overweight but at high risk for obesity-related complications clinical programs now often combine behavioral-based treatment with weight-loss medications or surgery.

Weight-loss aids: Buyer beware

American Family Physician, According to a 2004 review in Americans spent more than $1.3 billion on weight-loss supplements in 2001. Advertisements for weight-loss supplements seem to be everywhere television infomercials, popular magazines, even your e-mail inbox. "Eat the foods you love and still lose weight" and "Exercise in a bottle" are among the marketing ploys that sound too good to be true. And, for the most part, they are.

Take a look at the fine print on these products for the disclaimer that none of their statements have been verified by the FDA, which is responsible for ensuring the safety of all foods and medications on the market. In the case of medications, the FDA is responsible for testing effectiveness. For example, a cold medicine that claims to relieve nasal congestion must be proven to do so. However, weight-loss aids fall into a gray area in FDA regulation.

Weight-loss aids are neither foods nor drugs; rather, they are classed as dietary supplements. Congress created the category of dietary supplements under the Dietary Supplement Health and Education Act of 1994, in response to public pressure to loosen the FDA's tight control over a variety of products. As a result, individual nutrients, herbs, and "phytomedicinals" (plants supposed to have medicinal value) can be sold without being tested for effectiveness or safety, so long as they do not make direct health or therapeutic claims. Within these limits, manufacturers cannot say that their weight-loss aids will cure obesity or make you lose weight, but they can make indirect claims and this has led to a wide array of unfounded assertions on labels and in advertisements.

Some manufacturers of dietary supplements have been fined for false advertising. In 2006, the Federal Trade Commission ordered sellers making questionable weight-loss claims for skin gels and diet supplements to pay $3 million to settle fraud charges under federal law. For example, the skin gel ads claimed the gels would melt away fat wherever applied on a user's thighs, tummy, and even double chin.

But the FDA cannot take a product off the market unless it is found to be unsafe. Because the agency cannot test every one of the thousand supplements on the market, most face no danger of being removed.

Ma huang In 2004, however, the FDA banned the sale of ephedra ( in Chinese) after the compound was linked to a number of deaths and very serious side effects, including heart attacks, strokes, and seizures. In 2001, ephedra products comprised fewer than 1% of all dietary supplement sales, yet they were responsible for 64% of all herb-related complications reported to the U.S. Poison Control Centers during the same year. Despite the fact that ephedra-containing supplements are the only dietary supplements shown to help people lose weight (at least for up to six months), the potential risks far outweigh the benefits.

Despite the ban on ephedra itself, supplements containing ephedra-like compounds (which include ephedrine, norephedrine, and methylephedrine) are widely available over the Internet and in stores. They are often found in combination with caffeine or plant sources of caffeine, such as guarana and yerba mate, in weight-loss supplements. Note that two other ingredients found in some supplements, bitter orange and country mallow, contain chemicals related to ephedra and should also be avoided.

You should also steer clear of chitosan and guar gum, two more compounds found in weight-loss supplements. That's not because of any evidence that they are unsafe, but rather because studies show they don't help people lose weight. The FDA has also deemed spirulina (blue-green algae) ineffective for weight loss, and no information about its safety is available.

Making an informed decision

When you buy a commercial weight-loss formula or pill, it's important to know what you are buying. Inside that bottle bearing an enticing name, there may be as many as 1520 different substances, few if any of which will help you lose weight. Many supplements contain stimulants such as caffeine or herbs that contain caffeine, and some contain ingredients such as those related to ephedra that are known to be dangerous. Read the ingredients label carefully, and look up the ingredients in Table 3. Or, if they are not listed and you are not sure what the substances are, reconsider whether this product is a healthy choice.

American Family Physician What about the approximately 50 other different substances found in weight-loss supplements? The evidence as to whether they work is unclear, because study results are either insufficient or conflicting. And although some of them appear to be safe, others have unknown safety profiles. As a result, the authors of the study (all doctors at Harvard Medical School) say that people should be cautious about using any of these supplements. Table 3 summarizes their advice on common weight-loss supplements. You should let your doctor know if you choose to take one, and alert him or her immediately if you experience any side effects.

Table 3: Advice on ingredients found in common weight-loss supplements

Use with caution

These products appear to be safe but have unknown effectiveness:

Glucomannan
L-carnitine
Vitamin B5
Green tea
Psyllium

Use with extra caution

These products have unknown safety and effectiveness:

Apple cider vinegar
Cascara
Chromium picolinate
Conjugated linoleic acid (CLA)
Dandelion
Ginseng
Guggul
Hoodia (Hoodia gordonii)
Hydroxycitric acid (HCA) (Garcinia cambogia)
Laminaria
Licorice
Pyruvate
St. John's wort

Avoid as ineffective

These substances are not effective in promoting weight loss:

Chitosan
Guar gum

Avoid as dangerous

These substances have known or possible safety issues:

Ephedra alkaloidcaffeine combinations
Bitter orange
Country mallow

Weight-loss medications

Diet drugs have gotten a lot of press. In June of 2007, an over-the counter version of the fat-blocking drug orlistat (Xenical) hit drug store shelves. Dubbed Alli, the drug works by blocking fat absorption in the intestines and must be taken before every fat-containing meal. Many physicians and patients were enthusiastic about rimonabant (Acomplia), a drug that works by blocking the same receptors in the brain that cause the "munchies" in marijuana users. Rimonabant is currently available in many European countries. But in 2007, a federal advisory committee recommended against the drug's approval in the US, citing concerns that rimonabant may leave people vulnerable to neurological and psychiatric problemsincluding a higher risk of suicide.

Other currently available prescription weight-loss drugs include those that suppress or regulate appetite by altering levels of brain chemicals namely, sibutramine (Meridia) and phentermine (Adipex, Ionamin, others).

Of course, weight-loss drugs don't do the job by themselves. But for people whose health is at risk and who are struggling to reduce their weight through diet and exercise, drug therapy may increase the odds of success. Experts agree that weight-loss drugs, which all have side effects, are not for the mildly overweight or those who just want to lose a few pounds to improve their appearance.

Researchers have learned a lot about the biological causes of weight disorders, such as how genes influence the many systems that control weight. Weight-loss drugs can temporarily manipulate these systems. More than 200 drugs currently are in the testing phase.

Weight medications have a history of safety concerns. In the 1950s and 1960s, dieters took amphetamines to quell their appetites and boost their metabolisms until it was discovered that the pills were addictive and caused paranoia. The combination of fenfluramine and phentermine, popularly known as fen-phen, was widely used in the mid-1990s, until fenfluramine and another drug, dexfenfluramine, were linked to heart valve disease and withdrawn from the market. (Phentermine, the weaker but safe half of fen-phen, is still used.)

Until sibutramine was approved in 1997 for long-term use in obesity, the FDA had required that most such medications be prescribed for no longer than three months. Both sibutramine and orlistat are approved for use up to one year, but physicians may prescribe them for longer. Sibutramine is considered effective and safe for up to two years, although it can increase blood pressure and thus requires monitoring. Orlistat, which inhibits the body's ability to absorb fats, can interfere with the absorption of fat-soluble vitamins. Moreover, little is known about how safe it is to use weight-loss drugs for more than two years.

On the other hand, these medications have a role to play in medical treatment, especially now that obesity is recognized as a metabolic disease and not a failure of motivation or willpower, as was once thought. Clinicians are finding that obesity, like other chronic conditions, is often easier to manage with judicious, long-term medication use.

Who should take them?

One way to minimize the risks of these drugs is to prescribe them only for people who need them for health reasons: those who have obesity-related conditions such as type 2 diabetes or hypertension, or those at high risk for developing such disorders. Guidelines issued by the National Institutes of Health (NIH) advise that weight-loss drugs be given only to people with a BMI of 30 or more, or in the case of those with weight-related health problems a BMI of 27 or more. The use of diet drugs by people with lower BMIs is likely to pose more risks than benefits.

Be aware that weight-loss drugs aren't effective for everyone. Clinical guidelines suggest that if a person hasn't lost at least a pound a week in the first month on a weight-loss medication, she or he is unlikely to benefit from the drug. A drug that helps one person may be no better than a placebo for someone else. For example, people who overeat because of stress, bad habits, or emotional issues may benefit less from appetite suppressants than do people who overeat because of hunger. For them, psychotherapy or behavioral therapy may be a more appropriate first step.

How should they be taken?

The NIH guidelines make clear that weight-loss drugs should be used only in combination with lifestyle modifications. To lose weight over the long term, you need to recognize and change the behaviors that led to the weight gain. Otherwise, any weight you lose is likely to return.

New England Journal of Medicine Drug therapy works better when it's paired with an overall program of lifestyle change. A study published in 2005 in the showed that after one year, Meridia users who participated in a comprehensive counseling program that promoted a low-calorie diet and 30-minute daily walks lost twice as much weight as subjects who received counseling alone or Meridia alone.

Among its most important benefits, counseling can help establish realistic goals. The idea behind using weight-loss medications is to improve health and reduce disease risk, not to achieve an ideal body weight. A 5%10% reduction in weight over time is one common goal. But even more modest weight loss helps. One study of women with obesity demonstrated that those who intentionally lost any amount of weight experienced a 40%50% decrease in death from obesity-related cancers and a 30%40% decline in death from type 2 diabetes.

How do they work?

The prescription weight-loss medications on the market as of summer 2006 generally fall into three categories. (See Table 4 for details on each of these drugs.)

Noradrenergic agents. These medications increase levels of norepinephrine (also known as noradrenaline), a brain chemical that helps regulate appetite and resting energy expenditure (the amount of calories the body needs during inactivity). Phentermine is the safest. On average, people taking phentermine lose 213 pounds over a 6-month period. After that, weight loss tends to level off, as it does with other diet drugs. These drugs have several side effects; patients should be carefully re-evaluated after three months before continuing to take them.
Serotonin-norepinephrine reuptake inhibitors. The only weight-loss drug in this category is sibutramine (Meridia). It works by increasing the availability of serotonin and norepinephrine, brain chemicals that make people feel full and stimulate resting energy expenditure. Initial weight loss with sibutramine predicts long-term response to the drug: One study showed that people who lost more than 4 pounds in the first month were more likely to lose 10% of their body weight after 1 year than those who lost less weight initially.
Lipase inhibitor. The only lipase inhibitor currently available in the United States is orlistat (Xenical), which works by blocking the action of lipase, an enzyme released by the pancreas and intestine that helps digest dietary fat. It works about as well as the other medications, helping people lose about 5%8% of their body weight.

Other medications that are not specifically approved for weight loss cause some people to shed pounds. They include certain drugs used to treat depression, seizures, and diabetes.

Antidepressants. Certain antidepressant drugs, particularly bupropion (Wellbutrin), are sometimes prescribed on a short-term basis because they've been found to help some people lose weight. Most doctors prescribe this medication only for people who have mild to moderate obesity who also have symptoms of depression. Short-term studies showed that people taking bupropion lost about 4%5% of their weight, compared with less than 2% in people taking placebos.
Antiseizure drugs. Two medications used to treat seizure disorders, topiramate (Topamax) and zonisamide (Zonegran), are being studied as possible treatments for obesity. But topiramate's side effects (confusion and other thinking problems) make it unacceptable for most people. Zonisamide caused a 6% loss of body weight, compared with 1% in a control group, in one study. The main side effect was fatigue. But further, longer studies are needed before this medication is widely recommended.
Diabetes drugs. Most medications used to treat people with type 2 diabetes tend to cause weight gain, but two, metformin (Glucophage and others) and exenatide (Byetta), have the opposite effect for some people. In the Diabetes Prevention Program study, people taking metformin lost an average of 4% of their body weight over one to two years. Exenatide has similar effects, although it must be injected and may cause gastrointestinal problems. Both drugs should be taken only by people who have (or are at a high risk for developing) type 2 diabetes and are being closely monitored by a doctor.

Table 4: Medications used for weight loss
Drug	How it works	Possible side effects	Comments
FDA-approved for treating obesity
Orlistat (Xenical, Alli)	Cuts fat absorption in the intestine by up to 30%.	Oily stool leakage, gas, bloating, malabsorption of fat-soluble vitamins (A, D, E, and K).	₁₂ People taking orlistat should take supplements of fat-soluble vitamins and be closely monitored for vitamin B and iron deficiencies.
Phentermine (Adipex-P, Ionamin, others)	Increases levels of norepinephrine; increases energy expenditure; suppresses appetite.	Rapid heartbeat and high blood pressure, nervousness, restlessness, diarrhea.	Should not be taken by people with a history of heart disease, cardiac arrhythmia, stroke, or uncontrolled high blood pressure. Heart rate and blood pressure should be checked weekly for the first four weeks and after any change in dosing.
Sibutramine (Meridia)	Increases levels of norepinephrine and serotonin; increases energy expenditure; reduces food intake.	Elevated blood pressure.	Should not be taken by people with a history of heart disease, cardiac arrhythmia, stroke, or uncontrolled high blood pressure. Heart rate and blood pressure should be checked weekly for the first four weeks and after any change in dosing. Avoid if taking selective serotonin reuptake inhibitors (SSRIs) such as Prozac.
Approved for other indications but sometimes prescribed for weight loss
Bupropion (Wellbutrin, Zyban)	Increases levels of norepinephrine and dopamine and may help control appetite.	Dry mouth, agitation, constipation or diarrhea, headache, insomnia.	Approved for treating depression (Wellbutrin) and smoking cessation (Zyban).
Exenatide (Byetta)	Lowers blood sugar levels and stimulates a sense of fullness.	Acid or sour stomach, belching, diarrhea, dizziness, nervousness.	Given by injection only; approved for treating type 2 diabetes.
Metformin (Fortamet, Glucophage, Glumetza, others)	Lowers blood sugar levels.	Loss of appetite, metallic taste in mouth, stomachache, passing gas.	One of the few drugs used to treat type 2 diabetes that does not cause weight gain. Should not be taken by people who have kidney or liver disorders.
Topiramate (Topamax)	Mechanism unknown.	Vision problems, prickling or tingling sensations, dizziness, drowsiness, problems with thinking and memory.	Used to treat seizure disorders and migraines. Especially helpful in treating weight gain caused by antidepressants or other psychiatric medications.
Zonisamide (Zonegran)	Mechanism unknown.	Drowsiness, loss of appetite, upset stomach, vomiting, dizziness.	Used to treat seizure disorders.
*All medications are prescription-only except Alli, which will be an over-the-counter (lower-dose) version of Xenical, pending final FDA approval as of 2006.

Weight-loss surgery

For people with severe obesity, diet and medications may have little effect. In some cases, their best chance for long-term weight reduction and improved health may be surgery to promote weight loss, called bariatric surgery. The long-term results of bariatric surgery are impressive. Even more than a decade after surgery, 90% of those who've undergone gastric bypass, the most common bariatric procedure, manage to keep off an average of 50% of the excess weight. The result is a cure or substantial improvement in diabetes, sleep apnea, degenerative arthritis, and hypertension, and a reduction in risk factors for heart disease, including elevated cholesterol.

Surgeons have been doing bariatric surgery for several decades, but the number of people undergoing the procedure (most of whom are women) has soared from 36,700 in 2000 to 171,000 in 2005, according to figures from the American Society for Bariatric Surgery. The surge has been influenced not only by the growing number of people with severe obesity, but also by improved surgical techniques and high-profile success stories, such as NBC television weatherman Al Roker's loss of 100 pounds after gastric bypass in 2002.

Like all major operations, bariatric surgery has risks and severe obesity adds to those risks. Surgical treatment also requires lifelong medical monitoring and major changes in diet and lifestyle. But for most people with severe obesity, the health benefits far outweigh the risks.

Figure 6: Gastric bypass (Roux-en-Y)

Gastric bypass (Roux-en-Y)

Roux-en-Y (pronounced roo-en-why) gastric bypass was developed in the late 1960s after surgeons noticed that overweight patients who underwent similar gastric surgery for stomach ulcers lost weight. The upper part of the stomach is converted into a small pouch about the size of an egg. The small intestine is cut and one end is connected to the stomach pouch; the other end is reattached to the small intestine, creating a Y shape. This allows food to bypass most of the stomach and the upper part of the small intestine, although both continue to produce the gastric juices, enzymes, and other secretions needed for digestion. These drain into the intestine and mix with food at the crook of the Y.

Advantages: Patients lose weight rapidly for up to two years after surgery. Many maintain a loss of 60%70% of excess weight for 10 years or more. Gastric bypass is more effective in curing or improving obesity-related health problems than banding procedures. About 80% of people with type 2 diabetes who undergo the procedure are cured.

Disadvantages: Gastric bypass is more difficult to perform (whether done as open surgery or laparoscopically) than gastric banding and has a somewhat higher complication rate. It's also associated with a higher risk of vitamin and mineral deficiencies, which may require lifelong supplementation.

Annals of Internal Medicine National Institutes of Health (NIH) guidelines recommend bariatric surgery only for highly motivated people with a BMI of 40 or more and no success or only temporary success with other approaches to weight loss (see "Are you a candidate for bariatric surgery?"). This therapy may also be appropriate for people with moderate obesity (with BMIs between 35 and 40) if they have an obesity-related health problem, such as type 2 diabetes, heart disease, or sleep apnea. Some experts believe that certain people with milder obesity (BMIs between 30 and 35) might even benefit from this treatment. A 2006 study in the compared laparoscopic gastric banding with nonsurgical treatment (which involved a very low-calorie diet, weight-loss drugs, and behavioral change to improve diet and exercise habits) in 80 people with mild obesity. After two years, members of the surgery group had lost nearly 22% of their body weight, compared with 5.5% in the nonsurgical group. And those who had undergone surgery reported a better quality of life.

Table 5: Are you a candidate for bariatric surgery?
Bariatric surgery may be appropriate for people with BMIs of 40 or higher, along with people whose BMIs fall between 35 and 40 who also have an obesity-related health problem such as type 2 diabetes, heart disease, or sleep apnea.
Height	5' 2"	5' 6"	6'	Category
Body weight in pounds	136158	155179	184213	Overweight (2529 BMI) People in this category generally are not candidates for bariatric surgery.
164213	186241	221287	Obesity (3039 BMI) People with a BMI of 35 or over can be candidates if they also have an obesity-related health problem such as diabetes, heart disease, or sleep apnea.
?218	?247	?294	Severe obesity (40 BMI and over) People in this category can be good candidates.

Only experienced bariatric surgeons should perform the surgery (research suggests it's best to choose one who has performed at least 100 procedures), and patients should receive extensive medical, nutritional, and counseling services before and after surgery.

Bariatric techniques promote weight loss by various mechanisms, not all of them fully understood. Some procedures, such as gastric banding (see Figure 7) restrict food intake by making the stomach smaller, and also change the absorption of some fats and other nutrients. But stomach restriction and preventing nutrient absorption aren't the whole story. Experts believe that obesity surgery also acts through hormonal and neurohormonal pathways that change the body's response to food. People tend to feel fuller and less hungry. With gastric bypass, diabetes may resolve within two weeks of surgery. These changes can't be accounted for just by the weight loss. There are some hormonal changes throughout the body after the surgery that cause you to lose weight and correct the metabolic complications of obesity.

Figure 7: Gastric banding (adjustable)

Gastric banding (adjustable)

A silicone band about two inches around restricts stomach size to a small upper chamber, with an opening at the bottom to the rest of the stomach and digestive tract. The size of the band can be adjusted by injecting or withdrawing saline through a port implanted just under the skin. The procedure is sometimes called Lap-Band surgery after the brand name of the device used in the U.S.

Advantages: Gastric banding surgery is usually done laparoscopically with camera-guided instruments inserted through tiny incisions. Compared with more complicated procedures, such as gastric bypass, it has some advantages. It requires less time in the operating room and a shorter hospital stay. There are fewer post-surgical complications. And the band can be removed if necessary.

Disadvantages: Vomiting may occur if food intake is too rapid or the opening into the lower stomach is too narrow. The silicone band may wear, slip, or leak, necessitating another surgery. Compared with gastric bypass, there is generally less weight loss and weight loss is slower. There is less information on its long-term effectiveness.

A lot of research is aimed at finding out why weight-loss surgery is as effective as it is. It's been shown, for example, that levels of ghrelin, a hormone that stimulates appetite, fall after gastric bypass. Scientists have also cured diabetes in animals by simply bypassing the upper part of the intestine (duodenum) without decreasing the size of the stomach. The body's response to insulin and its production may also change. Learning more about these mechanisms may lead to the development of medications and other strategies that could make surgery unnecessary.

If you are considering bariatric surgery, your primary care provider will refer you to a bariatric surgeon or a center that specializes in bariatric procedures, where you'll be evaluated by clinicians specializing in medicine, nutrition, and psychology. The purpose is to make sure you are physically and mentally prepared for surgery (and the accompanying changes), are willing and able to participate in follow-up care and diet, and understand all the potential risks and benefits.

After surgery

₁₂ For the first few months after surgery, your appetite will decrease dramatically and you'll eat substantially less food. If you eat too quickly or too much, your stomach pouch can overfill, and you may vomit or feel pain in the chest and upper abdomen. You may need to take supplementary vitamins (especially vitamins B and D) and minerals (especially calcium and iron). After about a year, most people increase their food intake to 1,200 calories per day. You will need to be closely monitored by a physician, who can help address the common complications of bariatric surgery, such as gallstones, kidney stones, and ulcers. Some people develop other complications, such as a hernia at the incision site, or stenosis narrowing where the stomach is attached to the small intestine. After a high-carbohydrate meal, a person who has had gastric bypass surgery may suffer from "dumping syndrome," a reaction that causes flushing, sweating, severe fatigue, nausea, vomiting, diarrhea, and intestinal gas. People who lose 100 pounds or more sometimes need additional surgery to remove sagging skin that won't return to normal.

Insurance coverage for bariatric surgery is variable but generally improving. In February 2006, Medicare announced that it will cover most bariatric procedures, including gastric banding and Roux-en-Y gastric bypass, in appropriate patients who are treated at centers endorsed by the American College of Surgeons or the American Society for Bariatric Surgery. This decision may open the door to expanded coverage of other weight-loss treatments as well.

Other weight-loss therapies

Researchers have experimented with novel solutions that go beyond medication and surgery. Two such potential solutions for treating obesity are special devices that help prevent overeating. One is a pacemaker-like device that delivers low-level electric stimulation to the stomach; the other is a silicone stomach balloon filled with salt water. Although both have been tested and are used in other countries, neither has been approved by the FDA for use in the United States (as of 2006). Experts think these devices probably won't prove very effective alone, but may be useful for certain people in combination with other therapies.

Keeping the weight off

There is nothing more discouraging to someone on a weight-loss plan than the oft-cited statistic that 95% of people who lose weight will regain it within a few years. The difficulty in sticking with a long-term weight-maintenance plan is one of the main reasons that weight-loss programs fail. In an effort to uncover clues to successful weight loss, researchers have been collecting information on people who have lost weight and successfully kept it off for many years. This project, known as the National Weight Control Registry (NWCR), records what these people did to achieve their goals. Currently, the NWCR is tracking more than 5,000 people, who receive detailed questionnaires and annual follow-up surveys to examine their behavioral and psychological characteristics, as well as the strategies they use to keep weight off. Note, however, that these people are self-selected (that is, they chose to participate) and therefore represent only successful "losers," not the entire population of people who have tried to lose weight. There is no evidence that the techniques and approaches these people use are the key to success, because many other people have used similar approaches without success. Nonetheless, their stories may prove helpful or inspirational for some people.

Studying success

NWCR findings suggest that people who maintain weight loss over the long term are those who develop methods of incorporating healthy, low-calorie eating and regular physical activity into their daily lives. They are also highly motivated to continue doing so over the long term. Some are motivated by an experience that frightened them for example, finding out that they were at high risk for a serious illness. Others reported feeling extremely unhappy with the way they looked and felt.

Their diet plans and physical activities differ widely, but one thing that these individuals have in common is that they chose strategies that they liked, that fulfilled some personal goal, and that they could stick with. For example, one man reported that, as a teenager, he was able to lose 75 pounds, reducing his weight from 240 to 165 pounds, because he wanted to make himself more attractive to girls. Over the next 19 years, he gradually regained 24 pounds, reaching 189 pounds. At that point, however, he decided to prevent further weight gain by committing himself to regular exercise on a treadmill. Since then, his weight has dropped to 185 pounds, and he has maintained this weight for 2 years.

In what is certainly one of the greatest success stories in the registry, one woman managed to overcome a strong genetic predisposition toward obesity and lose more than half her weight. She had had obesity since childhood, and at age 36 she reached her greatest weight, 325 pounds. The turning point came when an earthquake shut down the elevator in her apartment building, and she found herself unable to climb the stairs to her apartment. Over the next 2 years she lost 160 pounds by dieting and exercising. She ate smaller portions of food, cut back on fat, and started walking regularly. She added biking, weight training, and yoga to her regimen of physical activity. She has maintained her new weight at 165 pounds for 4 years.

Not everyone can rely on an earthquake for motivation, but it is possible to search for motivating factors in your own life. For some people, serious health problems may serve that function; for others, a romantic interest may be key. Likewise, no weight-loss or treatment plan will work for everyone. Ultimately, you have to find a way to eat healthfully and get regular physical activity that you enjoy. For some people, the answer may be a vegetarian diet, scheduled tennis matches, and biking. Others might prefer having at least some lean meat or fish, and taking long walks for exercise.

British Medical Journal Research has shown that the more freedom people have in planning their weight-loss programs, the greater their prospects for success. A study in the compared the outcomes of women following two maintenance-diet plans having lost weight through a medically supervised weight-loss plan. Over a yearlong period, one group of women selected meals and snacks from a menu of foods that added up to a set number of calories per day. The other group could eat whatever they wanted within certain general guidelines. The guidelines involved avoiding fried foods, cutting back or eliminating the use of butter or margarine on bread, eating lean meats, and eating more complex carbohydrates, such as brown rice or whole-wheat bread. After one year, the women on the calorie-restricted diet regained an average of 9 pounds, but those who ate what they wanted within the healthy-eating guidelines regained less than half that amount.

Research has identified several characteristics of people who have successfully kept pounds off. These are listed below. People who want to lose weight might consider following their example.

Many people in the NWCR ate on a schedule of three meals and two snacks a day and didn't deviate from it.
Most also ate healthier foods in smaller amounts and exercised regularly and kept on doing these things even after they reached their target weights.
They generally reduced their consumption of junk foods, such as cookies, donuts, and ice cream.
They typically did not lose weight quickly, but they lost it consistently. Some people lost weight over a period of several years.

Other research shows that among half of all people who lost weight over the long term, frequent contact with a health care practitioner led to more successful weight-loss maintenance. Such visits, even if they lasted only a few minutes and consisted of little more than being weighed by a nurse, helped keep people motivated to eat healthfully and stay active enough to maintain their weight loss.

Glossary

bariatric surgery: One of several gastrointestinal operations that cause therapeutic weight loss.

body mass index (BMI): An estimate of an individual's relative body fat calculated from his or her height and weight.

calorie: The unit for measuring the amount of energy in food.

carbohydrate: The major component in fruits, milk, and starches such as bread, pasta, rice, and potatoes. Carbohydrates are one of the three primary nutrients (along with fats and proteins) and provide most of your body's fuel.

diabetes: A chronic metabolic disorder in which levels of blood glucose, or sugar, are elevated. Excess body weight raises the risk of developing this condition.

fat: One of the three major nutrients (along with carbohydrates and proteins). Fat is found in both animal and plant foods; however, fats from different sources have differing chemical compositions and health effects.

fiber: An indigestible substance found in plant foods.

glucose: The body's chief source of energy; a simple sugar that passes easily from the digestive tract into the bloodstream when you consume carbohydrates.

glycemic index: A scale for evaluating foods, based on the rate at which sugar is absorbed into the bloodstream after eating a specific food.

hypertension: High blood pressure. Individuals who are overweight or have obesity are at greater risk of developing high blood pressure.

low-calorie diet: A weight-loss diet that allows only 8001,500 calories a day.

metabolism: The rate at which your body uses energy, measured in calories.

monounsaturated fats: A type of fat found in peanut oil, canola oil, cashews, peanuts, many other nuts, and avocados.

obesity: Excess body fat, usually defined as a body mass index of 30 or more.

overweight: A condition marked by a body mass index of 25 to 30.

polyunsaturated fat: A type of fat found in corn, soybean, and other vegetable oils. It's also found in seeds, legumes, whole grains, and fatty fish, such as salmon and tuna.

protein: One of the three major nutrients (along with carbohydrates and fats). It is used by the body for building and repairing tissues. Protein is derived primarily from animal sources but can be found in some vegetables as well.

resting energy expenditure: The rate at which you burn calories while at rest. Resting energy expenditure accounts for 60%75% of daily energy expenditure.

saturated fat: A type of fat found in animal foods, such as meat, poultry skin, butter, and dairy products. Also found in palm and coconut oils.

trans fats: Processed fats that are solid at room temperature and include partially hydrogenated or hydrogenated vegetable oils and shortening. These fats are often found in commercial baked goods.

very low-calorie diet: A weight-loss diet that allows 800 or fewer calories per day (usually followed under medical supervision).

Resources

Organizations

American Diabetes Association AskADA@diabetes.org www.diabetes.org 1701 N. Beauregard St. Alexandria, VA 22311 800-342-2383 (toll free)

The leading professional organization devoted to research and treatment of diabetes, a common complication of overweight and obesity. Provides extensive information on nutrition and weight loss for people with diabetes.

American Dietetic Association www.eatright.org 120 S. Riverside Plaza, Suite 2000 Chicago, IL 60606 800-877-1600 (toll free)

A professional organization of registered dietitians. Provides information on nutrition and a list of dietitians in your area.

American Obesity Association www.obesity.org 1250 24th St., NW, Suite 300 Washington, DC 20037 202-776-7711

An advocacy group that works to eliminate laws and policies that negatively affect people with obesity. Also educates the public about obesity issues.

American Society for Bariatric Surgery info@asbs.org www.asbs.org 100 SW 75th St., Suite 201 Gainesville, FL 32607 352-331-4900

The leading professional organization for the study and support of surgical therapies for obesity. Provides public education and patient support programs.

American Society of Bariatric Physicians info@asbp.org www.asbp.org 2821 S. Parker Road, Suite 625 Aurora, CO 80014 303-770-2526

A professional organization of surgeons who perform bariatric surgery for weight loss. Provides names of surgeons in your area.

North American Association for the Study of Obesity www.naaso.org www.obesityresearch.org The Obesity Society 8630 Fenton St., Suite 918 Silver Spring, MD 20910 301-563-6526

The leading professional organization devoted to research and improvement of obesity. Provides public education and patient support programs.

Overeaters Anonymous www.oa.org P.O. Box 44020 Rio Rancho, NM 87174 505-891-2664

A nonprofit organization of support groups. Modeled after the 12-step Alcoholics Anonymous program.

Shape Up America! www.shapeup.org

A not-for-profit organization committed to raising awareness of obesity as a health issue. Provides evidence-based information and guidance on weight management.

Weight-Control Information Network win.niddk.nih.gov 1 WIN Way Bethesda, MD 20892 877-946-4627 (toll free)

An information service of the National Institute of Diabetes and Digestive and Kidney Diseases, which is part of the National Institutes of Health. Provides health professionals and consumers with science-based information on obesity, weight control, and nutrition.

Books

Eat, Drink, & Weigh Less: A Flexible and Delicious Way to Shrink Your Waist Without Going Hungry Mollie Katzen and Walter C. Willett, M.D. (Hyperion, 2006, 288 pages)

Written by a well-known cookbook author and the head of Harvard School of Public Health's Department of Nutrition, this book describes a flexible and medically sound weight-loss program that uses a "Body Score," a number that reflects your eating and exercise habits. The book provides diet and behavioral steps to boost your score and lose weight, as well as healthy, easy-to-prepare recipes.

The No Sweat Exercise Plan: Lose Weight, Get Healthy, and Live Longer Harvey B. Simon, M.D. (McGraw-Hill, 2005, 304 pages)

Written by a leading Harvard Medical School physician, this book introduces an innovative exercise plan that shows how to be healthy and lose weight through day-to-day activities and without working up a sweat. The book is based on sound scientific data and written for people who know they need to exercise to look better and improve their health, but who just aren't into heavy workouts.

The LEARN program for Weight Management, 10th Edition Kelly D. Brownell, Ph.D. (American Health Publishing Company, 2004, 266 pages)

The LEARN program (which stands for Lifestyle, Exercise, Attitudes, Relationships, and Nutrition) was developed by a weight-loss researcher at Yale University. The program describes more than 200 lifestyle changes intended to help people adopt new, healthier habits to lose weight.

Review Date: 2006-09-01

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