Vanadium
Vanadium is also a trace element found in several foods, including breakfast cereals, sunflower seeds, different vegetables, and in grains, wine, and beer. Vanadium may have direct insulin-like activity and may increase tissue sensitivity to insulin. However, there is insufficient evidence to set a recommended daily allowance as well as an adequate intake. The National Academy of Sciences set an upper intake level, based on kidney toxicity in laboratory animals, at 1.8 mg per day. Vanadium may produce various adverse GI effects, greenish tongue discoloration and it may accumulate in various tissues, and is toxic in high doses. It may potentiate the effects of digoxin, and with antiplatelet agents it may produce additive hypoglycemia with secretagoguges. It has been studied in both type 1 and type 2 diabetes, but only in a very small number of patients.
