8 Ways Sugar Ages You

What is ‘added sugar’?

The sugars that occur naturally in fruits, vegetables, grains and dairy are essential to a healthy diet, providing energy and acting as a delivery device for the thousands of nutrients in these foods. Indeed, they’ve been found to reduce the risk of chronic diseases such as diabetes, heart disease and even some cancers.

Added sugars, on the other hand, are the compounds that humans put into their food — from the spoonful of sugar in your coffee to the factory-made sweeteners manufacturers add to processed foods to increase flavor and extend shelf life. These are the sugars that are harmful and accelerate aging. On food labels, they are often the ingredients ending in “ose,” such as high-fructose corn syrup, sucrose, dextrose and maltose, among others. “Natural” sweeteners can have the same age-promoting effects: Cane sugar is almost entirely sucrose. Agave is mostly fructose.

Fructose may be more harmful than other sugar molecules because it is primarily metabolized by the liver, where it is readily converted into fat; in excessive amounts, it leads to increased fat accumulation and scarring in the liver. Manufacturers are now required to document added sugars on food labels, so there’s an obvious tip-off if the product contains harmful sugar.

Think of added sugars the way you’d think of alcohol: The extent of damage to your body is proportionate to the amount you consume, what scientists call “dose dependent.” Every gram of sugar interacts with your body in some way, Lustig says, but it’s the cumulative impact that portends the most damage and drives accelerated aging.

What sugar really does to your body

When sugar molecules bind to proteins and lipids in the body, they form harmful compounds called advanced glycation end products (AGEs). These AGEs accumulate in tissues, reducing their plasticity and flexibility, increasing inflammation, and creating oxidative stress in cells — all of which produce diseases, says Monica Serra, a health scientist administrator for the National Institute on Aging. In blood vessels and arteries, they can increase the risk of heart disease or strokes. In the kidneys, they can contribute to insulin resistance, and in the skin, they can deplete collagen and add to the appearance of aging.

“They affect every tissue in a negative way and across your entire lifespan, which is why we try to emphasize healthy habits in childhood,” says Serra. “By the time you get older, you see the impact of these dietary choices, at a time when you have less resilience.”

This is where fructose does its worst damage, says Lustig. “Every time glucose or fructose binds to a protein, you get an oxygen radical. If your body is making radicals faster than you can quench them, your cells undergo damage, and they eventually die. Fructose makes the reaction occur seven times faster and generates 100 times the number of oxygen radicals as glucose. Every time this process occurs, you age faster.”

8 ways sugar can harm your health

Sugar places an increased burden on an already aging body, says Dorothy Chiu, a postdoctoral scholar at the UCSF Osher Center for Integrative Health and coauthor of the UCSF study. Getting older puts us at greater risk for disease, she says, but “sugar is the icing on the cake.” Here’s what sugar can do:

1. Raises dementia risk

Excessive amounts of sugar can increase inflammation and weaken the blood-brain barrier, which can trigger cognitive decline, Serra says. In one study, researchers found that in older adults (average age 79), consuming more sugar may double the risk of developing dementia later in life. “People at highest risk got 32 percent of their calories from sugar versus the low group consuming only 17 percent of calories from sugar,” says Puja Agarwal, assistant professor of internal medicine at the Rush Alzheimer’s Disease Center at Rush University Medical Center and lead author of the study. “This study tells us consuming higher sugar or calories from sugar may impact risk for dementia.”

2. Makes your belly bigger

When you eat excess sugar, your liver metabolizes the fructose compound and converts it to fat, which accumulates in the liver. You gain weight when your liver stores excess fat instead of burning it off as energy. Fat accumulation can lead to higher cholesterol, insulin resistance and cardiovascular disease.

3. Hampers your nutritional status

As we get older, our need for calories declines, so to maintain the same body weight we need to eat less, says Alice H. Lichtenstein, senior scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University. “Consuming a diet high in sugar makes it challenging to also include enough healthy foods so that we balance calorie needs and meet our nutrient needs.”

4. Damages your liver

High sugar intake, especially fructose, can lead to nonalcoholic fatty liver disease, which is an excessive amount of fat in the liver that is associated with an increased risk of developing liver cancer.

5. Increases your risk of heart disease and stroke

Added sugar can elevate your blood pressure, promote chronic inflammation and increase levels of triglycerides, a type of fat that builds up in the bloodstream and increases your risk of heart disease. Excessive sugar intake damages the arteries and puts stress on the heart.

6. Ups your diabetes risk

Sugar causes rapid spikes in blood sugar levels, which can contribute to insulin resistance, a precursor to type 2 diabetes, and drives other major chronic diseases in older adults. In addition to aging and stress, sugar “can wreak havoc on insulin sensitivity and through various pathways accelerate aging in the body’s systems,” says UCSF’s Epel. “This is one of the most important metrics of health and aging.”

7. Worsens menopause symptoms

Postmenopausal women are more vulnerable to the effects of sugar because they have lower levels of estrogen and progesterone and become more insulin resistant. Some studies show that high sugar levels are also associated with more hot flashes in menopausal women. It may be because they cause spikes in blood sugar and dramatic drops. “It’s reasonable to conclude that reducing sugar may help reduce hot flashes for some individuals, but it has not been tested,” Epel adds.

8. Promotes tooth loss

Sugar can foster bacterial growth in the mouth, which, in turn, can produce acid that erodes the enamel on your teeth, causing cavities. Excess sugar can also lead to inflammation of the gums, leading to gum recession and tooth loss.

Bottom line: The occasional sugar indulgence isn’t harmful, but “be selective and only indulge when the option is your favorite,” Lichtenstein says. So yes, have the slice of birthday cake. But don’t have a party every day, OK?