Forrest H. Nielsen
Health and supplement stores now have a large number of powders, beverages and formulas containing vanadium, a mineral element unfamiliar to many consumers. The products are being sold as muscle, strength or performance enhancers, or found in supplements to improve glucose metabolism and prevent diabetes. Although there is some evidence that a little vanadium is beneficial for health, the amounts found in these products is alarming and may have toxic consequences.
Vanadium's emergence as a supplement came about because of the discovery that the mineral mimics insulin in animals treated to develop diabetes. Insulin helps build skeletal muscle by increasing amino acid incorporation into protein (muscle is protein) while retarding protein breakdown. Some people inferred that vanadium should act similarly in people, enhancing muscle building, strength and performance.
Disturbingly, the supplement makers have disregarded the fact that the amount of vanadium needed to mimic insulin in animal studies was extremely high--to the point of being toxic. These doses commonly caused poor appetite, poor growth, diarrhea, and death in many of the animal studies. Moreover, vanadium can cause biochemical changes in cells. These changes suggest that it has the potential to cause cancer when taken in high doses for an extended period of time.
Research at the Grand Forks Human Nutrition Research Center suggests that vanadium is an essential nutrient beneficial for thyroid hormone metabolism. I have suggested that the requirement to prevent possible deficiency is only about 10 to 20 micrograms (millionths of a gram) a day. That's about one- thousandth of that found in supplements, which contain milligram amounts of vanadium. Mineral elements when consumed at 1000 and often at 100 times the requirement are generally toxic.
Researchers have attempted to treat diabetics with vanadium, giving 100 to 125 milligrams a day for two to three weeks. These doses produced only mild beneficial effects. They were about one hundredth the dose needed to get good responses in animal studies, suggesting that much higher doses of vanadium are needed to markedly affect glucose metabolism in people. However, evidence exists that signs of vanadium toxicity appear in people with long term intakes of 10 to 20 milligrams per day, or about one- fifth the doses that gave the mild beneficial effects.
Taken together, these findings show that there is no nutritional basis for touting vanadium supplements as useful for the prevention or treatment of diabetes. And it is dangerous to attempt to use it in high doses for any purpose, such as building muscle and enhancing performance. Most diets provide enough vanadium to fill nutritional needs -- between 15 and 30 micrograms per day. Foods rich in vanadium include shellfish, whole grains, mushrooms and spices.
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