Throughout my career, I’ve met many people who were clinically overweight but incredibly fit. I’ve also met numerous people who were normal weight by definition and incredibly unfit. Any practitioner worth her salt knows that weight—or even body fat percentage—isn’t a standalone measure of fitness. And now a new study published in the European Heart Journal shows that "fat but fit" adults may be at no greater risk of developing or dying from heart disease or cancer than normal-weight fit individuals.
In the study, researchers found that among more than 40,000 adults, those who qualified as obese did not experience an increased risk of disease or early death if they were healthy (in terms of parameters like normal cholesterol levels and ideal blood pressure) and fit (as indicated by how well their heart and lungs performed).
At the start of the study, scientists measured participants’ heights, weights, waist measurements, and body fat percentages. The subjects also completed detailed questionnaires about their medical and lifestyle histories, had physicals, and performed treadmill tests, a measure of cardio-respiratory fitness. They were then followed for more than two decades or until they died.
The data revealed that 46 percent of the obese participants were considered “metabolically healthy,” and these fit-but-obese people had a 38 percent lower risk of death from any cause compared to their unfit obese peers. In addition, no significant difference was seen between the healthy/obese and the healthy/normal weight participants—the risk of developing or dying from heart disease or cancer was 30 to 50 percent lower for both healthy groups.
The conclusion: Fitness and health trump weight and body composition when it comes to long-term wellness. This is a notion I’ve been preaching for some time (check out my previous post about how to determine your ideal weight), and I think it’s critical because I’ve seen many people worsen their health and fitness in the pursuit of thinness. I’ve also worked in oncology and cardiac rehab, and there were thin patients in both settings.
Unfortunately our society is programmed to believe that weight determines health, or that you can’t possibly be obese and healthy, and neither it true. That doesn’t mean you need to abandon your weight-loss goals if you truly want to shed pounds. But it does mean that at any size, fitness and health should be your primary goals.
Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV, she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is S.A.S.S! Yourself Slim: Conquer Cravings, Drop Pounds and Lose Inches.