Fructose, not starches, may up weight

GAINESVILLE, Fla., Dec. 14 (UPI) -- There's a fair amount of evidence that starch-based foods don't cause weight gain like sugar-based foods, University of Florida researchers said.

Senior Author Dr. Richard Johnson, who reviewed several recent studies on fructose and obesity, said many diets are based on the glycemic index, which measures how foods affect blood glucose levels.

Because starches convert to glucose in the body, these diets tend to limit foods such as rice and potatoes, however, table sugar is composed of both glucose and fructose. Eating too much fructose causes uric acid levels to spike, which can block the ability of insulin to regulate how body cells use and store sugar and other nutrients for energy, leading to obesity, metabolic syndrome and type 2 diabetes, Johnson said.

"We think that fructose may have the unique ability to induce insulin resistance and features of the metabolic syndrome that other foods don't do so easily," Johnson said in a statement.

Studies at other institutions have shown that following a low-glycemic diet can reduce the risk for diabetes and heart disease, but the effect could occur because these dieters often are unintentionally limiting fructose as well by cutting out table sugar, Johnson said.

The findings are published in the European Journal of Nutrition.