Vanadium has been recognized by the American Dietetic Association as an essential mineral in human nutrition. Most research into vanadium has centred on its role in improving insulin action. In animal studies, it has been shown to improve glucose tolerance, inhibit cholesterol synthesis, and improve mineralization of the teeth and bones .
The following foods have the highest concentration of vanadium. For a more expansive list on food sources of specific nutrients visit Health Canada's Dietary Reference Intakes for Elements or USDA's National Nutrient Database
Some studies have shown that greater than 99% of the vanadium ingested is not absorbed.
Other food sources include:
- To improve insulin action: Vanadium has been used for diabetics and body builders in the form of vanadyl sulfate in order to improve insulin action. However, the clinical studies to support this use are lacking. Some preliminary studies have shown encouraging results 
No real signs and symptoms of vanadium deficiency have been established. Some researchers say that signs and symptoms of deficiency may include: 
In a study done on feeding goats a vanadium-deficient diet for 3 years resulting in: 
- birthing kids with irreversible bone deformities (some kids died within 3 days)
- the mother producing significantly less milk
Toxic signs and symptoms that have shown up during animal studies have included: 
- elevation in blood pressure
- reduction in coenzyme A and coenzyme Q10 levels
- stimulation of monoamine oxidase inhibitors
- interference with cellular energy production
In studies with humans, high dosages have resulted in: 
- no negative side effects were seen in non-insulin-dependent diabetic participants.
One other concern with vanadium is that high levels of vanadium have been found in the hair samples of patients with manic depression.
- Vanadyl and vanadate are the most biologically significant forms of vanadium. Vanadyl sulfate is the most popular form .
- The recommended dosages varies based on age and health status. To determine what your specific requirements are talk to your naturopathic doctor or other trained medical professional.
There is no established RDA for vanadium. 10-60mg daily appears to be safe and probably adequate.
- General Adverse Effects: The typical amount found in the diet (<30 mcg/day) appears to have low toxicity. Some experience gastrointestinal symptoms such as nausea, vomiting, diarrhea, cramps, and a green tongue .
- Precautions: those with hypoglycemia should avoid
- Interactions include: 
- Murray Michael T (2005) Encyclopedia of Nutritional Supplements, The Essential Guide for Improving Your Health Naturally, Prima Publishing
- Medlineplus 
- Bralley J Alexander and Lord Richard S (2005) Laboratory Evaluations in Molecular Medicine, Nutrients, Toxicants, and Cell Regulators Institute for Advances in Molecular Medince, GA
- Hendler Sheldon S., Rorvik David (Editors) (2008) PDR for Nutritional Supplements, Medical Economics Company Inc.