Vanadium has been known to be essential in rats and chickens longer than it has in humans. Rats store vanadium primarily in their bones and teeth. Vanadium is needed by some bacteria and can occasionally substitute for molybdenum. The ascidian worms use vanadium in their blood cells as hemovanadium, which makes green-colored blood cells.

Vanadium is present in our soil, though the amount varies; its distribution is similar to that of selenium. Some studies have shown decreased rates of heart disease in vanadium- and selenium-rich areas, such as many South American countries. Modern humans get vanadium contamination through the air from burning petroleum. With age, it may accumulate somewhat in the lungs, though it seems to be fairly nontoxic.

Vanadium absorption is modest at best, probably about 5-10 percent of that ingested. It is, however, used fairly rapidly. Most of it is eliminated in the feces; whatever is absorbed and not used is eliminated in the urine. In humans, vanadium is stored mainly in fat.

Sources: Vanadium content in the vegetable kingdom varies, mostly according to soil differences. It is generally present in low amounts in foods, probably most available in fats and vegetable oils, especially the unsaturated variety. Soy, sunflower, safflower, corn, and olive oils and the foods these oils come from all contain fair amounts of vanadium. Buckwheat, parsley, oats, rice, green beans, carrots, and cabbage also contain vanadium. Dill and radish have fairly high concentrations, while eggs have a moderate amount. Most fish are low, though oysters and herring have good levels.

Functions: Not much is known about vanadium function. Vanadium seems to be involved in catecholamine and lipid metabolism. It has been shown to have an effect in reducing the production of cholesterol. This may be related to the cholesterol-lowering potential of polyunsaturated oils (good sources of vanadium). Other research involves its role in calcium metabolism, in growth, reproduction, blood sugar regulation, and red blood cell production. The enzyme-stimulation role of vanadium may involve it in bone and tooth formation and, through the production of coenzyme A, in fat metabolism.

Uses: Since vanadium has been shown to help reduce cholesterol levels in some people, it may be helpful in treating atherosclerosis and heart disease and could play a role in reducing incidence of heart attack. It may also help in lowering elevated blood sugar levels. The 1932 and 1957 editions of Dorland's Medical Dictionary recommended use of vanadium in the treatment of diabetes, of neurasthenia, and, with selenium, of cancer. In 1958, it was further recommended for the treatment of atherosclerosis.

Deficiency and toxicity: Vanadium has been thought to be essentially nontoxic in humans, possibly because of poor absorption. However, recent studies have revealed elevated levels of vanadium in patients with mania and depression. Some toxicity can occur in rats. Vanadium is more commonly an industrial and environmental pollutant, though this has not been shown to be a concern. There is some vanadium in the air, more in winter because of burning of petroleum. Workers who clean vanadium-containing petroleum storage tanks inhale and absorb additional vanadium. The dust can be a bit irritating to the lungs, and the tongue may become somewhat green, neither of which seems to be a serious problem.