High-Glycemic Foods Linked to Endothelial Dysfunction
Flow-mediated dilation reduced after high-glycemic-index meals in overweight volunteers
13 june 2009-- High-glycemic carbohydrates may be linked to reduced flow-mediated dilation in overweight individuals, perhaps pointing to a connection between such foods and cardiovascular disease risk, according to research published in the June 16 issue of the Journal of the American College of Cardiology.
Talya Lavi, of the Chaim Sheba Medical Center in Tel Hashomer, Israel, and colleagues analyzed data from 56 healthy overweight and obese subjects without diabetes. After fasting overnight, the subjects had a different meal on four mornings spaced a week or two apart -- water (serving as placebo), glucose, cornflakes, or high-fiber cereal.
At 30 and 90 minutes, serum glucose levels were higher after the high-glycemic glucose and cornflake meals than the low-glycemic fiber meal, the researchers note. The percent flow-mediated dilation at two hours after the meal was reduced to a statistically significant level only after the glucose and cornflake meals. The rate of percent flow-mediated dilation reduction was not seen to be correlated with glucose levels during the study period.
"Our study shows that high-glycemic-index carbohydrate meals significantly suppress brachial artery percent flow-mediated dilation in nondiabetic, healthy, overweight and obese volunteers, an effect not necessarily caused by post-prandial blood glucose levels alone. Furthermore, the link between high-glycemic-index foods and endothelial dysfunction could play a major role in the association between high-glycemic-index foods intake and cardiovascular disease risk. Further research examining hormonal and cytokine signals resulting from high-glycemic-index meals and their influence on endothelial function is warranted," the authors conclude.