New United States research has found that individuals with a healthy body mass index (BMI) but who lead a sedentary lifestyle may be at the same risk for cardiovascular disease (CVD) as those who are overweight.
Carried out by researchers at the University of Florida, the new study looked at more than 43,000,000 adults aged 40 to 79 years who had taken part in the National Health and Nutrition Examination Survey, a nationally representative study that collects data from a combination of interviews, physical examinations and laboratory tests.
The participant sample included individuals with a healthy BMI (between 18.5 to 24.9) and an overweight BMI (between 25 to 29.9), with the researchers also measuring the participants’ sagittal abdominal diameter, which is a measure of fat in the gut region, and waist circumference.
Participants also self-reported on the amount of moderate to vigorous physical activity they engaged in, the amount of time spent sitting and whether they experienced shortness of breath either when hurrying or walking up a slight hill.
In addition, the team also calculated the participants’ American College of Cardiology and the American Heart Association, or ASCVD risk score, which takes into account factors such as age, sex, race/ethnicity, smoking status, diabetes status, cholesterol and more to calculate an individual’s risk of having a heart attack or stroke within the next 10 years. A score of 7.5 percent or higher is considered high risk.
None of the participants had a previous diagnosis of coronary heart disease, stroke or heart attack.
The findings, which can be found online ahead of print in the American Journal of Cardiology, showed that participants with a healthy BMI but an unhealthy sagittal abdominal diameter, unhealthy waist circumference, shortness of breath, and a more sedentary lifestyle, as suggested by engaging in lower than recommended levels of physical activity, showed similar rates of a high ASCVD risk as those who had an overweight BMI.
On the other hand, individuals with a healthy BMI and healthy lifestyle factors were significantly less likely than overweight adults to be at high risk for CVD.
“We have traditionally thought that people with a normal BMI are healthy and at low risk for heart disease, but increasingly we are finding that how much you weigh is not necessarily a measure of good health,” said lead investigator Arch G. Mainous III, Ph.D.
“Our study demonstrates that a sedentary lifestyle counters the benefit of being at a normal weight when it comes to heart disease risk,” he added. “Achieving a body mass index, or BMI, in the normal range shouldn’t give people a false sense of confidence they’re in good health. If you’re not exercising, you’re not doing enough.”
For those who want to increase their activity level, Mainous suggests following the Centers for Disease Control and Prevention’s physical activity guidelines, which recommend at least 150 minutes of moderate intensity exercise a week for adults, including both aerobic activity and strength training. JB