DEXA Scan: A Clearer Picture Of Your Bone, Muscle, and Body Composition

Welcome to another edition of the Doctor's Note where we talk about what's on our minds when it comes to your health.

This week I had the pleasure of sitting down with my longtime friend and colleague, Dr. James Denham, at Elite Health and Longevity in Johnson City, TN. We dove deep into the world of longevity medicine, focusing on why accurate measurements like DEXA scans and VO2 max testing are changing the game in preventive health. Dr. Denham shared his personal journey from pathology to longevity—including how a family history of heart disease and his wife's passion for weightlifting led them to open their state-of-the-art clinic. We both agreed that getting reliable data about your body isn’t just motivational—it’s the foundation for building a healthier, longer life.

One of the main takeaways from our conversation is just how transformative data-driven health decisions can be. We discussed how VO2 max, often overlooked outside athletic circles, is actually one of the strongest predictors of longevity. Improving your VO2 max—even by modest amounts—can slash your overall risk of death by up to 50%. We also addressed the importance of muscle mass, grip strength, and visceral adipose tissue (the dangerous fat around our organs) as critical health markers revealed by DEXA scans. If you’re on a medication like GLP-1 for weight loss, these scans are especially vital to ensure you’re not sacrificing muscle for quick results. Our message: don’t just guess about your progress—measure it, track it, and use those insights to optimize your health for years to come.

PODCAST NOTES 

• VO2 max is arguably the single strongest predictor of longevity in the scientific literature. A modest improvement—such as going from the bottom 25th percentile to the 50th percentile for your age and sex—can reduce all-cause mortality by as much as 50%. These gains are not reserved for elite athletes, but are achievable for almost anyone with consistent, thoughtful training. VO2 max reflects your body's ability to utilize oxygen during intense exercise, and the testing methods at clinics like Dr. Denham’s provide reliable, actionable baseline data.

• DEXA scans provide unparalleled detail and accuracy in body composition assessment. Unlike traditional scales or caliper measurements, DEXA breaks down lean muscle mass, bone density, body fat percentage, and, most importantly, visceral adipose tissue. This last category—internal fat around your organs—is a major risk factor for cardiovascular disease, diabetes, cancer, and dementia. Having a precise view of where you stand gives you a powerful tool for measuring progress and motivating long-term change.

• Muscle mass is ‘the currency of aging,’ and it’s non-negotiable for healthy longevity. We lose at least 1% of muscle annually as we age, meaning early and regular measurement is crucial. Muscle directly correlates to bone strength, metabolic health, and overall resilience against age-related decline. Performance Medicine, and now more mainstream practitioners, are focusing on supporting muscle growth through hormones, nutrition, and strength training for both men and women.

• Grip strength is a deceptively simple but vitally important marker of long-term health and functional fitness. Unlike one-off strength exercises, grip strength reflects years of consistent effort and is directly linked to overall strength, nutritional status, and risk for chronic disease. Even basic measures like how long you can dead-hang from a bar can reveal valuable information about your aging trajectory and should be part of routine testing.

• Fitness wearables like Whoop, Garmin, and Oura may be helpful for tracking trends but generally fail on providing accurate VO2 max readings. These devices estimate rather than measure, leading to discrepancies as large as 10 points above or below your true numbers. Clinics equipped with lab-grade treadmills and bikes, plus real-time oxygen/CO2 measurement, are the gold standard for actionable VO2 max testing.

• GLP-1 medications, while effective for weight loss, bring an increased risk of muscle loss if not managed correctly. Dr. Denham highlighted the importance of baseline DEXA scans before starting such drugs, and regular follow-up while on them. Losing muscle alongside fat, especially quickly, can leave someone less healthy despite being smaller. Proper exercise and nutrition—with special attention to protein and resistance training—are essential for maintaining muscle while losing fat.

• Early and regular baseline testing is a critical, often neglected strategy in preventive medicine. Insurance won’t cover DEXA bone density scans until age 65, but bone and muscle loss often start decades earlier. Dr. Denham advocates for scanning by age 40 if possible—which allows for early detection, proactive changes, and a way to monitor interventions without waiting for symptoms to appear.

• Optimal health requires a multifaceted approach: strength training, proper protein intake, possibly creatine supplementation, attention to hormone balance, sleep, and regular objective measurement. Working harder doesn't always mean working smarter—real data makes all the difference. Whether it's preventing dementia or heart disease, or simply staying strong and independent as you age, these combined strategies offer the best chance at extending both lifespan and health span.

As I always say, data doesn’t lie—and neither does a truthful approach to your health. If you’re curious about where you stand or want to optimize your health journey, don’t put it off. Consider getting your baseline measurements now, whether it’s VO2 max, a DEXA scan, or even simple grip strength. Talk to a health professional about your risks and your goals, and make decisions based on real data. If you’re in the Tri-Cities area, I highly recommend you visit Dr. Denham at Elite Health and Longevity—his clinic is setting a new standard for preventive, personalized medicine. 

Stay educated. Stay healthy. 

Till next week.