Endothelial dysfunction is often the first event in cardiovascular disease, stroke, nerve damage, and retinopathy. But the endothelium can be restored with antioxidant therapy --and polyphenols which give fruits and vegetables their vibrant colors--are shown to help. Here's a recent study in diabetics.

Polyphenols present a promising approach to restoring normal endothelial function in people with diabetes, according to a review calling for more research on this potential ‘antioxidant therapy’.