There’s no such thing as healthy obesity, based on a 30–year study that found obese women with no cardiovascular risk factors still faced increased risk for heart disease. Findings also show normal-weight women with risk factors like high blood pressure and diabetes face increased risk for heart disease, highlighting the importance of prevention.
Published in The Lancet, this study analyzed data from 90,257 women who were followed from 1980–2010. Participants were from the Nurses’ Health Study, which has tracked the health of a group of U.S. female nurses since the 1970s.
The goal of the study was to see how both weight and underlying metabolic health impact risk for heart disease. Metabolic health is a broad term that describes underlying markers of health, which can impact risk for heart disease. In this study, those markers included high blood pressure, high cholesterol and diabetes—all of which greatly increase risk for heart disease.
During the 30-year study, participants completed questionnaires every few years about their health, lifestyle and weight. All were free of heart disease at the start of the study, but 7% had experienced heart attack or stroke during the study period.
After analysis, researchers found that both weight and metabolic health had a significant impact on risk for heart events.
Overall, women who were obese but had no cardiovascular risk factors were 39% more likely to develop heart disease than healthy, normal-weight women. That means obesity, alone, increases risk for heart disease, even when women are otherwise healthy. Findings also cast doubt on the “obesity paradox,” which suggests obesity may have a protective effect on some individuals.
However, findings also suggest that weight isn’t the only factor that impacts risk for heart disease. Even in normal weight women, poor metabolic health increased risk for heart events more than twofold. For overweight and obese women with risk factors, that risk was even higher.
The concern is that even the healthiest women are likely to develop risk factors over time, which eventually puts them at increased risk for heart disease.
In this study, 84% of obese women and 68% of normal-weight women with good metabolic health had developed at least one cardiovascular risk factor after 20 years. Researchers found that risk for heart events was significantly higher in women who developed poor metabolic health over the study period.
The take-home message, according to authors, is that both weight and metabolic health are key to preventing heart disease. On their own, obesity and poor metabolic health can increase risk for heart disease. But together, these risk factors can more than triple risk for heart events like heart attack and stroke.
Therefore, it’s important that women with obesity or any other risk factors like high blood pressure or diabetes take steps to improve their health.