When lean healthy young adults gained about 9 pounds, the functioning of their blood vessel lining became impaired -- but shedding the weight restored proper functioning, according to a Mayo Clinic research report.
The finding is important because this vessel disorder, known as endothelial dysfunction, is a predictor of heart attacks and stroke, and the effects of modest weight gain on the disorder were not previously known.
The Mayo Clinic team presented the findings at the American Heart Association's Scientific Sessions 2007.
Significance of the Mayo Clinic Study
The study is the first randomized, blinded, controlled trial to assess the effects of weight gain -- and subsequent weight loss -- on endothelial function. Endothelial cells line the blood vessels. When not functioning correctly, they impede blood flow, which can predispose a person to heart attack or stroke. Determining how modest weight gain affects the condition was important due to the growing number of overweight adults worldwide.
“The effects of obesity on heart health receives a lot of attention, but less scrutiny has been given to the impact on the endothelium of modest weight gain in otherwise healthy people,” says Virend Somers, M.D., Ph.D., Mayo Clinic cardiologist and senior author. “In fact, many adults accept this kind of weight gain -- 9 or 10 pounds -- as just part of aging. The assumption has generally been that a modest rise in body fat was more an issue of going up a clothing size, not a health issue. This study suggests otherwise, providing evidence that may help change our cultural attitude to the implications of modest weight gain as we age -- and perhaps strengthen the argument for diet and exercise to control weight as a means of protecting against cardiovascular disease.”
The study's first author, Abel Romero Corral, M.D., of Mayo Clinic, says, “There are three parts to the take-home message here: One is that in healthy people, modest weight gain results in impaired endothelial function -- even in the absence of changes in blood pressure. The second is the encouraging news: endothelial function recovers after weight loss. The third point is that it is visceral fat -- the abdominal fat that surrounds internal organs -- rather than fat deposited as subcutaneous fat, just under the skin, that predicts endothelial dysfunction.”
About the Study