Researchers at the Peninsula Medical School in Plymouth, England, say resveratrol -- also present in seeds, peanuts and red wine -- can protect against cellular damage to blood vessels caused by high production of glucose in diabetes.

Principal investigator Dr. Matt Whiteman says elevated levels of glucose that circulate in the blood of patients with diabetes causes micro- and macrovascular complications by damaging mitochondria -- the tiny power plants within cells responsible for generating energy. When they are damaged they can leak electrons and make highly damaging "free radicals."

"Resveratrol or related compounds could be used to block the damaging effect of glucose which in turn might fight the often life threatening complications that accompany diabetes," Whiteman said in a statement. "It could well be the basis of effective diet-based therapies for the prevention of vascular damage caused by hyperglycemia in the future."

The findings are published in the journal Diabetes, Obesity and Metabolism.