The Best Time to Get a DEXA Scan? Earlier Than You Think

She was 29, an elite triathlete, and by every visible measure — lean, strong, disciplined — the picture of health. But she’d fractured bones twice in 18 months. When I ordered a DEXA scan, it showed she already had osteopenia, the precursor to the bone-thinning disease osteoporosis. I had her add calories and high-dose vitamins D and K, temporarily reduce her training intensity, and add resistance training to get her bone density back up to healthy levels. 

That scan probably saved her from a catastrophic fracture long before she would have had her first routine screening. It also changed how I think about using DEXA scans.

In traditional medicine, physicians generally recommend DEXA — short for dual-energy X-ray absorptiometry —  scans after age 65 for females and 70 for males to screen for osteoporosis.¹

However, in longevity medicine, we recommend full-body DEXA scans decades earlier to analyze and track three key longevity markers:

• bone mineral density
• muscle mass
• fat mass

Repeated over time, DEXA scans provide a comprehensive snapshot of your bone density and metabolic health, giving doctors a way to test whether lifestyle changes and medications are improving them. Getting a DEXA at an earlier age offers something rare in traditional medicine: a hyperpersonalized prescription for optimized health and longevity. 

What DEXA Scans Measure

DEXA uses low-dose X-rays to create a detailed picture of your bone density, muscle, and fat mass. This information helps longevity physicians catch developing health problems before they progress to disease.² 

Bone mass and density 

Most people don’t worry about bone health until after midlife, when declining estrogen and testosterone accelerate bone loss. Women can lose up to 20% of their bone density in the five to seven years following menopause.³ Men face similar risks as testosterone declines, which happens at a rate of 1%–2% per year, starting around age 35.⁴ 

By the time your doctor recommends a DEXA scan in your 60s or 70s, bone loss may have been progressing silently for decades. Osteoporosis makes bones porous and prone to fracture. Hip fractures, which are common after bone loss, are the most severe. After breaking a hip, up to 20% of formerly independent people end up in long-term nursing care, 40% never walk independently again, and 60% require assistance for as long as a year. One quarter of adults never regain full physical function, and nearly 1 in 4 people pass away within 12 months.^{5 6}

How earlier DEXA scans can help 

A baseline DEXA in a woman’s early 30s might reveal bone loss that can be reversed or at least significantly improved with strength training or consuming more calcium-rich foods.

After age 65, medications can improve bone density but will never fully restore it. Those same medications are more effective in premenopausal women with bone loss because younger bones have more active cells that are better at building new bone than breaking it down.⁷ For that reason, it’s critical to catch developing bone loss decades earlier, when bone-strengthening measures can still restore bone density to healthy levels.

When it comes to improving bone mass, there are two windows of opportunity:

• Before age 30: Weight-bearing exercise and a healthy diet function like a bone mineral savings account, prompting cells to deposit more minerals into bone than they remove.⁸ 
• Ages 30–55: A healthy lifestyle can help you maintain your existing bone mass—but it won’t allow you to significantly expand it. You can increase bone mass after 55, but it’s more challenging, as breakdown outpaces formation. 

Fat mass and visceral fat

Between ages 40–66, the typical person gains 0.6–1.1 pounds of fat per year.⁹ Age-related slowing of fat metabolism makes it harder to prevent this creeping fat gain, even when you haven’t changed what you eat or how much you move. In one study, metabolism decreases led to an average weight gain of 20% over 13 years.¹⁰ 

The concern is less about total fat mass than where it accumulates. As sex hormone levels shift with age in men and women, excess body fat tends to accumulate in the midsection, around the liver, kidneys, and intestines. This fat — visceral fat — releases inflammatory chemicals directly into the bloodstream, increasing the risk for: ¹¹ 

• Heart disease
• High blood cholesterol
• High blood pressure
• Insulin resistance and diabetes

One study showed that the amount of visceral fat you have in your 30s or 40s can predict atherosclerosis (plaque buildup in the arteries) decades later.¹² Visceral fat is also closely tied to metabolic syndrome and fatty liver disease, and can predict your risk of dying prematurely from any cause.¹³

How earlier DEXA scans can help

A DEXA scan can give you a detailed picture of your body composition, which is a proportion of three body fat metrics that predict your future health and longevity:

• Total body fat percentage: the percentage of body fat compared to muscle, bone, and lean tissue
• Visceral adipose tissue (VAT): the amount of fat deposited in the abdomen around the internal organs 
• Regional composition: how much fat you carry in your arms, legs, or trunk, as well as whether your fat storage takes a gynoid (pear) or android (apple) shape.

Without a DEXA scan, visceral fat accumulates undetected. 

Up to half of women with a BMI in the normal range (18.5–24.9) have body fat in excess of 32%–35%, which is in the overfat to obese range.¹⁴ In a study of 5,944 people with normal BMIs, those with excess visceral fat were at increased risk of developing metabolic syndrome over the next six years.¹⁵

Muscle mass 

Skeletal muscle is one of the most important — and most overlooked — longevity organs in the body. It burns calories, regulates blood sugar, slows cellular aging, and secretes anti-inflammatory proteins that protect our tissues as we age.^{16 17}

Muscle mass starts to decline around age 30, typically by around 3%–5% per decade. The older you get, the faster the rate of decline. By midlife, the typical person loses 0.5%–1% of their muscle mass per year.¹⁸

This gradual muscle loss — sarcopenia — is directly associated with age-related increases in fat mass and is a key driver of aging, disability, and shortened life, contributing to some of the most prevalent diseases of aging:^{19 20 21 22 23 24}

• Insulin resistance 
• Type 2 diabetes
• Heart disease
• Lung disease 
• Dementia

Magnetic resonance imaging (MRI) and computed tomography (CT) scans are considered gold-standard tests for measuring muscle mass, but they’re more expensive, less widely available, and, for CT scans, deliver much more radiation than DEXA.^{25 26}

How earlier DEXA scans can help

Getting a DEXA scan at an earlier age helps identify muscle loss when it’s easier to reverse. I like to use DEXA to track body composition before and after patients start taking weight loss medications such as semaglutide (Ozempic, Rybelsus) and tirzepatide (Mounjaro, Zepbound). 

After taking tirzepatide for six months, one 42-year-old’s DEXA revealed that he had lost a stunning 7 pounds of

muscle mass — a change invisible on a traditional scale. Targeted increases in protein intake, resistance training, and creatine supplementation stabilized his lean mass on the next scan while fat loss continued. Without that monitoring, the loss would have gone undetected and compounded. 

Resting Metabolic Rate (RMR)

Each pound of muscle burns calories just to maintain itself. So resting metabolic weight (RMR) is the number of calories your body needs to maintain your weight at rest.²⁷

Many people make the mistake of overly restricting calories in an effort to lose weight. By aiming too low, they do, in fact, lose weight, but they also lose a significant amount of muscle tissue and bone, research shows.²⁸ Less muscle equals a slower metabolism. This, in turn, creates a vicious cycle of having to eat less to avoid weight gain, further eroding muscle tissue and bone, and increasing the risk of developing osteoporosis and sarcopenia. 

How earlier DEXA scans can help

DEXA software uses your lean and fat tissue readings to estimate your resting metabolic rate, which can be helpful when making decisions about how much to eat and how much to exercise. 

Overall health

For many diseases, a change in body composition is often the first hint that something is developing. Muscle loss, for example, is common in people with rheumatoid arthritis, cancer, eating disorders, and irritable bowel disease. ^{29 30 31 32}

Identifying these shifts through repeated DEXA scans creates an opportunity for earlier investigation and intervention. 

Who Benefits Most From DEXA Scans? 

Getting a DEXA scan at a younger age is a simple, cost-effective way to optimize health and fitness and reduce disease risk.

Health and fitness enthusiasts 

Though just about everyone would benefit from knowing their body composition, this metric is especially useful for:

• Executives and other high-performers who need to be at the top of their game, mentally and physically 
• Athletes who must maintain tight control of their body composition to excel in competition
• People taking GLP-1 medications, which can reduce lean muscle mass
• Anyone pursuing longevity optimization

Sometimes when we do a baseline DEXA, it confirms that someone’s lifestyle is perfectly calibrated. Hone Health CEO Saad Alam underwent his first DEXA scan in his early 40s at  BodySpec, a national provider of clinical-grade DEXA body composition scans. His total body fat was 16.7%, and his visceral fat was 0.35 pounds, indicating that he was healthier than 92% of men his age. His lean mass was 21.4 kg/m² — better than 82% of men his age. His average bone mineral density was 1.52 g/cm², higher than that of 89% of men. No interventions were needed. 

Other times, these baseline scans indicate that changes are in order — the case with the 29-year-old triathlete I mentioned earlier.

Because muscle and fat levels both respond quickly to lifestyle changes, we typically recommend DEXA scans once every six to 12 months. Monitoring the results from these scans helps me offer patients more detailed, personalized suggestions for nutrition, exercise, and supplements.

Anyone seeking to monitor and prevent disease

For patients whose primary goal is long-term disease prevention, getting a DEXA every year or two is generally sufficient to see if your diet and exercise habits and any medications you’re taking are affecting your body composition. 

Some types of people have a higher risk of bone loss and would benefit from more frequent screenings: ³³

• Small body frames
• Thyroid disease
• Eating disorders
• Extremely restrictive diets that omit most calcium-rich foods
• A history of gastrointestinal surgery 
• Health conditions that are treated with steroids and other bone- weakening medicines
• Medical conditions associated with low bone mass, including celiac disease, cancer, and rheumatoid arthritis 
• Alcohol use disorder

For people considered low risk for developing osteoporosis, we generally recommend a baseline DEXA scan around age 30, with follow-up scans every 5 years. If their baseline scan reveals low bone mass, we follow up more often, every 1 to 3 years.

FAQs 

About the author

James R. Staheli, D.O., is the Medical Director for Broad Health, Hone Health’s affiliated medical practice and a family medicine doctor in Atlanta, Georgia.