By Craig T. Zebuda, MD, DipACLM
Chief Medical Officer, Yunara Life
One of the most common questions I hear from patients interested in preventive health and longevity is, “What should I actually be measuring?”
It’s a reasonable question. We live in a world of wearables, health apps, blood tests, and endless streams of health data. With so much information available, it can be difficult to know which measurements truly matter.
After years practicing emergency medicine and urgent care, I’ve become increasingly interested in the metrics that help us identify risk before it becomes disease. Among the tools we use in preventive medicine, DEXA is one of the most informative because it provides insight into several important aspects of aging that are often overlooked until problems develop.
Most people associate DEXA scans with osteoporosis screening, and for good reason. DEXA remains the gold standard for measuring bone mineral density and identifying osteopenia or osteoporosis before a fracture occurs. What many people don’t realize is that modern DEXA technology can provide a much broader picture of health than bone density alone.
For much of modern medicine, body weight served as a convenient proxy for health. Increasingly, we recognize that body composition is often the more meaningful measure. Muscle mass, visceral fat, and bone density each provide important information about how we are aging and the health risks we may face in the future. DEXA allows us to evaluate all three in a single examination, making it one of the most valuable tools available for understanding the physical changes that influence healthspan and longevity.
Weight alone tells us remarkably little. Two individuals can weigh exactly the same amount and have dramatically different levels of muscle, body fat, visceral fat, and metabolic risk. Even body mass index, while useful at a population level, often fails to capture these important differences. Body composition tells a more complete story.
One area that receives increasing attention in longevity research is skeletal muscle. We naturally lose muscle mass as we age, a process known as sarcopenia. This loss is associated with reduced strength, impaired mobility, increased risk of falls, loss of independence, and higher rates of illness and mortality. Preserving muscle is increasingly recognized as one of the most important components of healthy aging.
Visceral fat deserves equal attention. Unlike subcutaneous fat, which sits beneath the skin, visceral fat surrounds internal organs and is strongly associated with insulin resistance, cardiovascular disease, metabolic dysfunction, and chronic inflammation. Because visceral fat cannot be accurately assessed from body weight alone, many patients are surprised to learn how much additional information body composition testing can provide.
Bone health is another area where prevention matters. Osteoporosis often develops silently, with many individuals remaining unaware of declining bone density until a fracture occurs. Early identification creates an opportunity to intervene through resistance training, nutrition, lifestyle modification, and medical treatment when appropriate.
For some patients, we also perform vertebral fracture assessment, or VFA, at the time of the DEXA scan. Vertebral compression fractures frequently go undiagnosed because they may develop gradually or be mistaken for routine back pain. Identifying these fractures can be clinically important because a prior vertebral fracture substantially increases the risk of future fractures and may influence treatment recommendations.
When viewed together, bone density, muscle mass, and visceral fat provide a much more comprehensive understanding of health than a number on a scale ever could.
Longevity is often discussed in terms of lifespan, but most patients are interested in something more meaningful. They want to remain active, independent, strong, and healthy for as long as possible. They want to continue traveling, exercising, playing with grandchildren, pursuing hobbies, and maintaining the quality of life that makes those additional years worthwhile.
Those outcomes are influenced by many factors, but body composition and bone health are among the most important and measurable. DEXA provides a window into both, allowing us to identify risks earlier and make more informed decisions about how to age well.