What a Body Composition Screening Is — and What It Says About Your Health
Health ConditionsGeneral Health

What a Body Composition Screening Is — and What It Says About Your Health

What a Body Composition Screening Is — and What It Says About Your Health
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Published on October 22, 2025
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A body composition test measures percentages of fat, bone, and muscle in the body. It can provide a snapshot of your overall health, inform strategies to improve health, and help gauge progress toward health and fitness goals.

Body composition scans are becoming increasingly accessible and are even offered at many gyms and fitness studios as an alternative to body mass index (BMI) measurements.

What Is a Body Composition Test?

There are various types of body composition tests (more on these below). Still, each one measures the percentages of fat and fat-free mass (muscle and bone) in the body. Knowing these percentages can help identify health risks like excess visceral fat (a type of fat located around the abdomen and organs that is more strongly associated with chronic diseases than other types of fat) and low bone density (a condition where bones have less mineral content than they should, increasing the risk of osteoporosis and fractures).

It can also help gauge progress in exercise and nutrition efforts that the scale may miss, such as muscle gain.

These tests typically involve a quick, noninvasive body scan using a machine.

A body composition scan provides a more accurate snapshot of overall health than a BMI score. Whereas a body composition test identifies how much body fat you have and where it’s distributed in the body — along with muscle and bone — BMI estimates body fat by using just weight and height. This simple weight-to-height ratio doesn’t account for what makes up the body weight, whether it’s muscle, bone, or fat.

Relying only on BMI to calculate body fat, for example, may misclassify muscular people as being overweight or having obesity. “Their BMI may be in the obese range, but they don’t have a lot of visceral fat, and, therefore, are likely at a lower risk of developing diseases that we associate with higher fat proportions,” says Angela Cavanna, DO, clinical associate professor of medicine at the Touro College of Osteopathic Medicine in Middletown, New York.

Body composition tests are available in many physicians’ offices and fitness and personal training facilities. They typically cost between $50 and $175 out of pocket. However, tests may be covered by insurance if they’re ordered by a physician and you have risk factors for health conditions such as osteoporosis.

Who Should Get Body Composition Screening?

Knowing your body composition can help you manage your weight and assess the effectiveness of your diet or exercise program.

 A body composition test can reveal a decrease in body fat and an increase in muscle mass, proving that your efforts are working even if the scale suggests otherwise, Dr. Cavanna says.
Body composition testing can also help identify certain health issues. Older adults, for instance, may maintain a stable weight while losing muscle and gaining fat. This age-related shift may not be apparent solely from body weight or BMI. “That can put them at risk of various diseases and also for falls,” Cavanna says.

A body composition scan can also be helpful for people who have a health condition that’s making them underweight (such as undernourished individuals or someone with a muscle-wasting syndrome like HIV) or overweight (such as those with type 2 diabetes or congestive heart failure), Cavanna adds. It can help determine whether their body weight is primarily made up of fat (a cause for concern) or muscle.

Types of Body Composition Tests

There are several types of body composition tests. They work in different ways and have different costs. Some providers may allow you to receive these body composition tests without a prescription, but others may require a doctor’s approval.

Dual Energy X-Ray Absorptiometry (DEXA/DXA) Scan

A DEXA scan, also known as a DXA scan, is the name of a body composition test that’s commonly used to measure bone density to diagnose osteoporosis, and is performed using a machine made by different manufacturers. It also measures body fat and muscle to determine your muscle-to-fat ratio and visceral fat.

 This test is considered more accurate than other methods, such as bioelectrical impedance (covered below). It uses low-dose X-rays to directly measure body composition, whereas the accuracy of methods like bioelectrical impedance can be affected by hydration and food intake.

For the test, you’ll lie down and remain still as a scanner passing a high- and low-energy X-ray beam moves over your body.

 It takes about 15 minutes to complete.

 A DEXA scan typically costs $160 to $175 without insurance.

A DEXA scan can help you manage weight and screen for bone diseases such as osteopenia and osteoporosis, says Russell F. Camhi, DO, a primary care sports medicine physician with the Northwell Health Orthopedic Institute in Great Neck, New York.

DEXA isn’t recommended for children or pregnant women because of the radiation in the X-rays, and the equipment can’t accommodate those with a BMI of 35 or higher (this is considered a severe category of obesity).

 It’s also unsafe to get a DEXA scan if you have surgical implants or a heart pacemaker.

Bod Pod

The Bod Pod is a human-sized, egg-shaped device that uses air displacement to determine your body fat and lean body mass.

 It’s considered the gold standard of body composition measurement.

 Currently, the Bod Pod is also the only device available that uses air displacement plethysmography, a technique for measuring body composition by calculating the volume of air it displaces.
The procedure typically takes 15 minutes and involves sitting inside the device while wearing form-fitting clothing and a swim cap. The Bod Pod collects your body’s volume and mass by measuring changes in air pressure when you’re inside the chamber, and then calculates your body density and composition.

 There are no restrictions, but the Bod Pod may feel uncomfortable for those who don’t like small spaces.

The Bod Pod can also determine your metabolic rate (the number of calories your body needs to perform basic functions) and total energy expenditure (the total number of calories your body needs each day). It typically costs less than $100.

Bioelectrical Impedance Assessment (BIA)/InBody Scan

BIA technology uses an electrical current to measure body fat, muscle mass, and water content. The current passes through body fluids, fat, muscle, and bone at different speeds. The BIA device collects this data and uses it to calculate your body composition.

InBody is the brand name of a popular BIA device. To use it, you’ll stand on a scanner with sensor electrodes touching various parts of your body and grip the two device arms.

 Then, a painless, noninvasive electrical current travels through your body for approximately 30 seconds.

 Your results are immediately available on a touch-screen display.

InBody tends to be the quickest and least expensive option (typically costing about $50). However, Cavanna warns that it’s also the least accurate. For example, your ratio of body water to fat can change significantly if you’re sick, dehydrated, or if you’ve lost weight. BIA technology is also less accurate for people with a BMI of 35 or higher.

Understanding Your Body Composition Test Results

Body composition test results typically indicate your percentage of body fat, bone density, and muscle mass. You can present the results of your test to a physician, personal trainer, or nutritionist, who can help create a personalized nutrition plan or make exercise recommendations for you if your results fall outside the normal ranges.

Body Fat

A healthy body fat percentage varies depending on age and sex. The rates range from 25 to 31 percent for women and 18 to 24 percent for men.

Fat is essential for regulating digestion, energy, and hormones. As such, having too much or too little fat can create health issues.

 Excess body fat — visceral body fat, in particular — can increase your risk of obesity, cardiovascular disease, type 2 diabetes, and some cancers.

Too little body fat, on the other hand, can indicate an underlying health issue like cancer or heart or kidney failure.

Bone Density

Measuring bone density is essential, as low bone mass indicates brittle bones that are prone to breaking. Bone density tests (such as DEXA) can also help diagnose bone diseases such as osteoporosis and osteopenia.

Your bone density results are compared with the average results of healthy people of your same sex and ethnicity between the ages of 25 and 35. The difference between your result and the average is called your T-score. A positive T-score means your bones are stronger than normal, while a negative T-score means they’re weaker. A T-score plus or minus 1 indicates normal bone density. A T-score of 1 to 2.5 below indicates low bone mass, and a T-score of 2.5 or more below indicates osteoporosis.

Muscle

There’s no set target for the percentage of muscle mass. Still, it can be helpful to get a baseline of your muscle mass percentage, so it can be compared with future measurements, says Sarah Wick, RD, CSSD, a board-certified specialist in sports dietetics and the sports nutrition program director at The Ohio State University Wexner Medical Center in Columbus.

For older adults in particular, regular measurements can help indicate whether their muscle mass is declining. This helps assess their risk of falls and other health concerns, such as sarcopenia (age-related muscle loss).

But, typically, if you have a health issue that’s associated with declining muscle mass, chances are that your doctor can identify it without the results of a body composition test, due to the presence of other symptoms, Wick says.

Measuring muscle mass percentage can also show progress as you’re following a strength and nutrition program. “It’s great to be able to test and look at changes over time to see how you’re doing,” Wick says.

The Takeaway

  • Body composition scans measure percentages of fat, bone, and muscle in the body. These tests offer a more accurate snapshot of your overall health than a BMI score.
  • Standard body composition tests include DEXA scans, Bod Pod testing, and bioelectrical impedance assessments. These tests vary in cost and are often available at doctors’ offices and fitness centers.
  • Knowing your body composition information can help you gauge your progress during a diet and exercise program. It may also reveal potential health issues to your healthcare providers.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. Body Composition. UC Davis Health.
  2. Tone Your Bones. The University of Alabama at Birmingham.
  3. Body Composition Testing. Appalachian State University.
  4. Muscle Loss in Older Adults and What to Do About It. Tufts University School of Medicine. February 9, 2021.
  5. DXA Body Composition Analysis. UC Davis Health.
  6. Body Fat. Harvard T.H. Chan School of Public Health. August 2022.
  7. How Does Body Composition Test Work? Wooster Community Hospital. June 14, 2019.
  8. Body Composition Testing. UC Berkeley.
  9. InBody Scanning: What You Need to Know. Prince William County Government. November 4, 2024.
  10. Body Fat Percentage vs. BMI — Which Is Important? Baylor College of Medicine. January 4, 2024.
  11. Bone Densitometry. Johns Hopkins Medicine.
  12. Muscle Atrophy. Cleveland Clinic. January 21, 2022.
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Scott Haak, PT, DPT, MTC, CSCS

Medical Reviewer

Scott Haak, PT, DPT, has been a member of the Mayo Clinic staff since 2000. Dr. Haak serves as faculty for the Sports Medicine Fellowship program at Mayo Clinic Florida. He is certified by the NSCA (National Strength and Conditioning Association) as a CSCS (Certified Strength and Conditioning Specialist), is a Certified USA Weightlifting Coach and Certified USA Football Coach, and possesses a MTC (Manual Therapy Certification) from the University of St. Augustine for Health Sciences.

Haak is an exercise enthusiast and enjoys running, weightlifting, and sports performance training. He is the president and director of coaching of a youth tackle football organization, JDL Providence Football, and currently coaches high school football and weight lifting.

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Moira Lawler

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Moira Lawler is a journalist who has spent more than a decade covering a range of health and lifestyle topics, including women's health, nutrition, fitness, mental health, and travel. She received a bachelor's degree from Northwestern University’s Medill School of Journalism and lives in the Chicago suburbs with her husband, two young children, and a giant brown labradoodle.
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