Blueberries may help reduce belly fat, diabetes risk

NEW YORK A new University of Michigan Cardiovascular Center study suggested that a blueberry-enriched diet can reduce belly fat and diabetes risk.

The new research, presented April 19 at the Experimental Biology convention in New Orleans, gives tantalizing clues to the potential of blueberries in reducing risk factors for cardiovascular disease and metabolic syndrome. The effect is thought to be due to the high level of phytochemicals – naturally occurring antioxidants – that blueberries contain.

The researchers studied the effect of blueberries (freeze dried blueberries crushed into a powder) that were mixed into the rat diet, as part of either a low- or high-fat diet. They performed many comparisons between the rats consuming the test diets and the control rats receiving no blueberry powder. All the rats were from a research breed that is prone to being severely overweight.

In all, after 90 days, the rats that received the blueberry-enriched powder, measured as 2% of their diet, had less abdominal fat, lower triglycerides, lower cholesterol, and improved fasting glucose and insulin sensitivity, which are measures of how well the body processes glucose for energy.

The rats in the study were similar to Americans who suffer fatty liver disease and metabolic syndrome as a result of high-fat diets and obesity. Metabolic syndrome is a group of health problems that include too much fat around the waist, elevated blood pressure, elevated blood sugar, high triglycerides, and together these conditions increase the risk of heart attacks, strokes and diabetes.

While regular blueberry intake reduced these risks for cardiovascular disease and metabolic syndrome, the health benefits were even better when combined with a low-fat diet.

“Some measurements were changed by blueberry even if the rats were on a high fat diet,” says E. Mitchell Seymour, M.S., lead researcher and manager of the U-M Cardioprotection Research Laboratory. “We found by looking at fat muscle tissue, that blueberry intake affected genes related to fat-burning and storage. Looking at muscle tissue, we saw altered genes related to glucose uptake.”