For years, Dr. Steven Blair of the Cooper Institute in Dallas asserted in media nationwide that regular vigorous exercise would protect people from a heart attack, no matter what their body size. Corpulent himself, Dr. Blair religiously got on a treadmill several times a week.
“Too bad he was wrong,” observes Dr. William McCarthy, UCLA School of Public Health and member of the Pritikin Scientific Advisory Board. Recently, Dr. Blair has been suffering heart problems.
And recently, research has found that it’s not okay to be fit and fat. A study of 27,000+ women found that those who were overweight and physically active were significantly less heart-healthy than those who were both normal weight and active.*
11 Biomarkers Measured
The scientists examined the effect of physical activity and body mass index (BMI) separately and in combination by measuring 11 different biomarkers for cardiovascular health, including LDL “bad” cholesterol, total cholesterol, triglyceride fats, and inflammatory markers like C-reactive protein. Average age of the women was 54.
Lower levels of physical activity and higher BMIs were each associated with adverse levels of nearly all biomarkers, but high BMI proved even nastier in its effects than sedentary living. “High BMI was more strongly related to adverse cardiovascular biomarker levels than physical inactivity,” stated lead investigator Samia Mora, MD, and colleagues from the Center for Cardiovascular Disease Prevention at Brigham and Women’s Hospital in Boston.
The worst-case scenario was being overweight and sedentary. And yes, exercise did provide some protection. For all categories of weight, from thin to obese, a physically active lifestyle was associated with more favorable heart biomarkers than a sedentary lifestyle.
But being active was not as protective as being normal weight. Sedentary normal-weight women tended to be more heart-healthy than overweight women who exercised.
Most Favorable Combination
And finally, having both – a normal-weight body and an active lifestyle – netted the most favorable heart biomarkers of all.
Agrees Dr. McCarthy of UCLA: “A physically active lifestyle will not by itself protect a person against heart disease if that person does not also eat healthfully. Steve Blair has long enjoyed steaks. Admittedly, it took awhile, but eventually his diet caught up with him.”
JAMA, 2006; 295:1412