Grapes protect against diabetes in rodents

A new study published in the May edition of the Journal of Nutrition shows that consuming grapes protected against the destruction of insulin-producing beta cells in the pancreas, significantly reducing the incidence of diabetes in laboratory rodents. Scientist believe that naturally-occurring antioxidants contained in grapes, known as polyphenols, are responsible for this beneficial impact.

The results of this study showed that grapes reduced the infiltration of immune cells into the islets of Langerhans, the specific area of the pancreas where the insulin-producing beta cells reside, thus preventing their damaging effects on the beta cells. Grapes also reduced the levels of an inflammatory protein in spleen cells, known as tumor necrosis factor-alpha.

Commenting on the results, principal investigator Susan Zunino stated that, "in this study, we observed first-hand [the effect of grapes] on two of three critical components for the prevention of type 1 diabetes: the preservation of the beta cells and the inhibition of inflammation. Other studies have shown that quercetin and anthocyanins, which are phytonutrients present in grapes, enhanced insulin secretion and sensitivity, which is the third critical component. Clearly more studies need to be done to fully define the mechanisms of action for the grapes and their potential as a dietary intervention for diabetes."