Obesity Influenced by Genetics Less Harmful to Heart Health Than That Linked to Lifestyle, Study Finds

Overweight people with a genetic predisposition for obesity have a lower risk of cardiovascular disease (CVD) compared with those whose obesity is largely driven by lifestyle and other environmental factors, according to a new study in eClinicalMedicine. Still, both groups are at higher risk for CVD compared with non-obese individuals, the research finds. As obesity rates increase worldwide, researchers have worked to tease apart the condition's genetic and environmental causes, but it has remained unclear why the risk of developing CVD varies so widely among obese individuals. To investigate, a team led by Karolinska Institute scientists analyzed data on thousands of people participating in the Swedish Twin Registry, combining polygenic risk scores of body mass index with data on the incidence of CVD among registry participants. They find that, in terms of CVD, obesity influenced by genetic predisposition was less harmful than obesity influenced by environmental factors. The finding, the study's authors write, supports the theory that genetically influenced obesity is not associated with negative health outcomes to the same extent environmentally influenced obesity is, suggesting that obesity in itself does not directly influence CVD risk. They note, however, that obesity was associated with CVD in all cases.