Weight

What Your Waist Circumference Says About Your Health

Because BMI can only show so much

Kristen Fischer,

AARP

Published April 14, 2026

Close-up of a person measuring their waist with a tape measure

Getty Images

Key takeaways

Waist circumference can flag weight-related health risks that BMI can’t.
People with a normal BMI can still have greater health risks if they have a lot of belly fat.
Your doctor may not use waist circumference, but it’s simple to measure at home.

Hopping on a scale is a good way to keep tabs on your weight, but wrapping a tape measure around your waist may be a better way to assess weight-related health risks.

Waist circumference is a better indicator of health risks compared to body mass index (BMI), some research shows.

For decades, experts have tried to characterize obesity with BMI, explains Dr. Sohail Zahid, a cardiology fellow at Johns Hopkins School of Medicine. The problem is that some people may have a low BMI but a lot of belly fat, which is linked to a host of health problems. Other people have good muscle mass and less belly fat but high BMI readings, Zahid notes. Those people may be better off because they have more muscle, even though they are classified negatively.

Subcutaneous fat beneath the skin around most of your body differs from deeper visceral fat, or belly fat, which is stored around organs. Visceral fat is associated with type 2 diabetes, liver disease, stroke and cognitive decline.

BMI can be a good screening tool, but it’s not the end-all, be-all on an individual level, Zahid says. Waist circumference is “another way to personalize your risk for fat-related issues,” Zahid says. Though we know BMI can lie in terms of risks, it’s a useful tool to provide an initial assessment of risk, he adds.

You don’t have to pick one over the other, but it helps to know how to use these measurements to determine your risks.

BMI vs. waist measurements

Here are a few ways to measure fat and body composition.

BMI

BMI divides your weight in kilograms by your height in meters squared. If your BMI is under 18.5, you’re classified as underweight. A BMI of 18.5 to 24.9 is considered normal, a BMI of 25 to 29.9 is deemed overweight and a BMI of 30 and up is obese.

Waist circumference

To calculate, wrap a tape measure around your waist to determine how many inches it is. To do that, stand up and find the top of your left and right hip bones (the iliac crests). Place the tape measure just above that, around your entire waist, and connect the two points, making sure the tape is parallel to the floor and positioned snugly against the skin, says Kamil Faridi, an assistant professor in cardiovascular medicine at Yale School of Medicine. For some people, the tape measure covers the belly button. As long as you measure in the same spot consistently, that can help you monitor your waist circumference.

Ideally, women should have a waist circumference of less than 35 inches, and men less than 40 inches, for optimal health. Asian adults have lower cutoffs: approximately 35.5 inches for men and 31.5 inches for women, Faridi notes.

Most Popular

Waist-to-hip ratio

Waist-to-hip ratio divides your waist circumference by your hip circumference, the largest measurement around your hips. A 2023 report in JAMA Network Open followed 387,672 participants until their deaths, tracking those who developed weight-related health problems like high blood pressure, heart disease and type 2 diabetes. Waist-to-hip ratio was a better indicator of future health issues than BMI, as it probably better reflected how much visceral fat people had, according to the study.

Waist-to-height ratio

Waist-to-height ratio is calculated by dividing your waist circumference by your height. When researchers compared waist-to-hip and waist-to-height ratios, they found people with higher numbers for each had poorer physical performance, a 2025 study in Aging said. Waist-to-height ratio was better than BMI in predicting heart disease risk, a 2025 report in The Lancet Regional Health showed.

Medical imaging

The dual-energy X-ray absorptiometry (DXA) scan can gauge body composition, but it exposes you to radiation and can be costly: It’s usually not covered by insurance for body composition evaluation purposes.

Waist circumference versus BMI

Although there is fairly good evidence that waist circumference is superior to BMI, you shouldn’t discount BMI entirely, experts say.

“We’re not saying BMI serves no purpose,” notes Dr. JoAnn Manson, chief of the preventive medicine division at Brigham and Women’s Hospital in Boston.

A waist-based reading is helpful independently of BMI and even for people with normal BMI, Manson says. If your waist circumference is high and your BMI is normal, the waist measurement can still spot increased risk while the BMI can’t, Manson adds.

Where fat fits in

Before you roll out a measuring tape, it’s a good idea to understand how fat influences your health risks.

Abdominal fat tends to be a greater risk factor for chronic disease compared to fat around other parts of our bodies, Manson says.

“When it’s in the abdomen, it tends to be more strongly associated with inflammation and with insulin resistance,” Manson adds.

Visceral fat can be bad for you because it releases hormones that can lead to inflammation and a stress response, Zahid says. It also can impact how your body uses and stores fat.

“Fat is not just inert; it can be harmful if it’s in excess,” Zahid points out.

Measuring your waist

Zahid believes health care providers should monitor waist circumference more regularly, though doing so is not the norm yet.

If your doctor does not use waist circumference and uses only BMI, you can ask them to measure your waist or do it yourself.

If you monitor your waist size weekly or monthly, it can give you a glimpse into your risk — if the number increases, you may be packing on more fat and your health risks could go up, but knowing this means you can intervene.

How to shed fat

If your waist circumference is higher than the suggested range, contact your health care provider so they can evaluate cardiovascular risk factors like blood sugar, blood pressure, cholesterol and kidney function, says Faridi.

While you can’t target losing visceral fat over subcutaneous fat, you can lower the amount of fat in your body by burning more energy than you take in, creating a calorie deficit.

Eating a plant-rich, high-fiber diet can help too, as can avoiding too much sugar, saturated fat, sodium, tobacco and ultra-processed foods, Faridi says. He recommends exercising at a moderate to vigorous level for at least 150 minutes per week. Steering clear of too much alcohol is also key to improving waist circumference and overall health, he adds.

“When all these habits are combined, they result in health benefits that go far beyond weight control, including prevention of heart disease, stroke and cancer, and can dramatically improve mental health and quality of life,” he says.

Obesity in Older Adults

The prevalence of obesity is about 46 percent in people ages 40 to 59. That number drops to about 39 percent in those over 60. Obesity is linked to chronic diseases, mobility issues, sleeping and breathing problems and a decline in the ability to perform activities of daily living.

Waist-based measurements can be especially useful for older adults who may have a decline in BMI due to a loss of muscle mass, says Manson.

High BMI isn’t the only weight concern for older adults, though. A loss of lean body mass can contribute to a lower BMI, which is linked to health issues such as frailty, as well as mortality.

%{postComment}%

The key takeaways were created with the assistance of generative AI. An AARP editor reviewed and refined the content for accuracy and clarity.

Kristen Fischer is a contributing writer at AARP based at the Jersey Shore. She has also written for Health, WebMD, and McKnights and is the author of Zoo Zen: A Yoga Story for Kids.

Unlock Access to AARP Members Edition

Join AARP to Continue

Already a Member? Login

Losing Weight as You Age

Maintain a Healthy Weight