Hi Paul,
If you Google "bilberry and diabetes" you will get a ton of hits, but I soon spotted that they are all from organisations who are trying to sell bilberry leaf concoctions and I could find absolutely nothing on research into its effectiveness except this from The University of Maryland Medical Centre:
"Bilberry leaves have traditionally been used to control blood sugar levels in people with diabetes. Animal studies suggest bilberry may be effective, but no human studies have been done, so bilberry is not recommended for this use."
Edited by Dennis
Sorry - forgot to add this bit:
"Anthocyanosides found in bilberry fruits may also be useful for people with vision problems. During World War II, British fighter pilots reported improved nighttime vision after eating bilberry jam. Studies have shown mixed, mainly negative results, however. Bilberry has also been suggested as a treatment for retinopathy (damage to the retina) because anthocyanosides appear to help protect the retina. Bilberry has also been suggested as treatment to prevent cataracts. However, studies are lacking in both areas."
