Vanadium remains a relatively unknown trace element, as its uses are still being targeted in various clinical applications worldwide. There is little information available concerning the biochemical reactions that result upon human ingestion of this trace mineral. Scientists have discovered, however, that like selenium, vanadium’s content in food is directly dependant upon the concentrations present in the soil. Once consumed, vanadium is stored primarily in fatty tissues, with the remaining amounts stored in the kidney, liver, spleen, or bone.
The human body contains roughly 20 - 25 milligrams of vanadium that is distributed throughout the body, mainly in the organs listed above. Because little is known about its functioning in the human body, there is speculation over its essentiality in our daily diet. In the past, vanadium was prescribed as a common ‘cure-all’ when taken in extreme dosages. We now know that excessive intake of vanadium is unnecessary and may possibly contribute to toxicity in humans. More research is necessary to further discover vanadium bioavailability and its targeted application in higher species (i.e. human beings).
Because of the varying amounts in foods due to concentrations present in soil, a food graph is omitted. The richest sources of vanadium are achieved through various oils, including specialized fats, vegetable and olive oils, soy, sunflower, and corn; all have been shown to provide a fair amount of this mineral. Grains and vegetables also contain moderate amounts of vanadium. Sea foods, with the exception of herring and oysters, contain minute amounts and should not be used as a major food source contributor, for achieving proper daily intakes of selenium.
Again, the absorption rate of vanadium varies greatly and is dependent upon the various mineral concentrations of soils in any given geographical region of the world. This variation of available vanadium in soil content directly impacts this trace mineral’s content of the food sources consumed by the population in that particular area. Upon intake, vanadium is used rapidly by the body and we absorb a modest 5-10 percent of this mineral. It is easily processed and rapidly lost via excretion processes of the body.
The efficacy of vanadium supplementation has been widely debated by the medical community. Many researchers feel that there remains an indecisive and undefined use for vanadium in human biology. Although this may be true, extensive and research has been conducted upon animals; there has also been numerous studies applied towards certain conditions in the human body with varying success.
Diabetics are, first and foremost, the major demographic concerning the clinical application associating vanadium supplementation to an irregular condition of the body or disease. Both types of diabetes, both type I and II, may yield moderate benefit when supplemental vanadyl sulfate is added to already existing treatment protocol.  Vanadyl Sulfate may lower blood glucose levels and improve insulin sensitivity in both type I and type II diabetics. In fact, one study in particular not only highlighted vandyl sulfate supplementation successes on glucose levels of those suffering from type II diabetes, but also showed significant reductions in total LDL (bad) blood serum cholesterol levels.  This is thought to be caused by vanadium’s role in lipid metabolism.
Over the past decade, the sports world has been the leader in the nutritional supplementation of vanadium. Nutritional supplements in the form of vanadyl sulfate remain popular to this day. It has been used in body building and as a performance enhancer in other sports; to increase the muscle during rigorous resistance activities performed by these athletes.  Despite its popularity, more vanadium research to warrant vanadyl sulfate supplementation and its purported relationship between muscle growth and performance enhancement; as well as tolerability and safety.
Vanadium also plays an important role as a catecholamine (compound that directly impacts the physiological effects of neurotransmitters and hormone levels), namely, epinephrine, norepinepherine, and dopamine. Due to this characteristic, vanadium levels may be in direct correlation to irregular conditions associated with psychosis of the brain. Bipolar disorder and manic depressive states may be directly linked to elevated levels of vanadium in the circulatory system. [4, 5] According to some practitioners, vanadium supplements may assist individuals suffering from these disorders in times of depression or irregular hormonal fluctuations in the brain, along with assisting one’s overall sense of emotional well being.
There remains a nonattendance for a recommended dietary allowance (RDA) for vanadium. The average median intake for a well-balanced adult diet is approximately 2 milligrams per day. This amount seems adequate in fulfilling the requirements needed to complete the many biochemical processes within the body. However, with the modern inconsistencies found in the typical Western diet, this number is likely much lower than what has been theorized. The most commonly supplemented forms of vanadium are vanadyl sulfate and vanadate.
Because vanadium has not been widely researched in regards to dosages, the effectiveness and safety of vanadium supplementation is a concern. Tolerable upper level intakes achieved from dietary sources range from 0.5 to 1.0 milligrams per day. According to the Food and Nutrition Board and the Institutes of Medicine, no more than 1.8 milligrams should be consumed per day. 
There are no findings regarding vanadium deficiency in a human subject. This is likely due the minuscule requirements needed to fulfill daily tasks, and also because of poor absorption rates by humans.
However, deficiency states may adversely impact cardiovascular and kidney health. Vanadium may also negatively impact the reproductive abilities of both male and females, increase cholesterol and triglyceride levels, and incidence of infant mortality.
A toxicity of vanadium is more likely caused by external pollutants, rather than excessive dosages taken orally. Exposure to vanadium-containing inhalants may result the irritation of the lungs (bronchitis), and after prolonged exposure, the development of asthma.  Higher dosages, often over 15 milligrams per day may also result in kidney or liver damage.
Early signs and symptoms of an overdose may include stomach pain that progresses to diarrhea and/or nausea, vomiting, and flatulence.
1. Cohen N, Halberstam M, Shilimovich P, Chang CJ, Shamoon H, Rosseti L. Oral vandyl-sulfate improves hepatic and peripheral insulin sensitivity in patients with non-insulin dependent diabetes mellitus. J Clin Invest. 1995;95(6):2501-2509.
2. Preuss HG, Jarell ST, Scheckenbach R, Lieberman S, Anderson RA. Comparative effects of chromium, vanadium, and Gymnenma sylvestre on sugar-induced blood pressure elevations in SHR. J Am Coll Nutr. 1998;17(2): 116-123.
3. Kreider RB. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Med. 1999;27(2): 97-110.
4. Naylor GJ, Corrigan FM, Smith AH, Connelly P, Ward Nl. Further studies of vanadium in depressive psychosis. Br J Psychiatry. 1987;150: 656-661.
5. Naylor GJ, Smith AH, Bryce-Smith D, Ward NI. Tissue vanadium levels in manic-depressive psychosis. Psychol Med. 1984;14(4):767-772.
6. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. National Academies Press. 2002. http://www.pdrhealth.com/drug_info/nmdrugprofiles/herbaldrugs/101840.shtml (Chapters 1, 2, and 8)
7. Irsigler GB, Visser PJ, Spangenberg PA. Asthma and chemical bronchitis in vanadium plant workers. Am J Ind Med. 1999;35(4): 366-374.