# 11.8 Molybdenum
## 11.8.1 Sources

Although molybdenum can be found in a large number of plant foods its levels depend greatly on the molybdenum soil content in the regions where plants are grown. Legumes, grain products, nuts, and leafy green vegetables are all sources of molybdenum. Animals don’t have concentrations of the mineral that are as high but sufficient quantities for nutritional sources may be found in liver and milk. Reaching the recommended daily intake of dairy will often be an adequate nutritional source of molybdenum in the diet. Average dietary intake of molybdenum is difficult for researchers to determine because there isn’t yet a uniform analytical utilized in studies to determine molybdenum levels. In addition to this reports vary widely across the globe due to the changing levels of the mineral in the soils where crops are grown. Even with variations molybdenum intake is consistently above the daily requirement.

## 11.8.2 Functions

The three primary metalloenzymes which utilize molybdenum are xanthine dehydrogenase/oxidase, aldehyde oxidase, and sulfite oxidase. Xanthine dehydrogenase/oxidase works actively in different types of tissue to convert purines into uric acid. A genetic condition called xanthinuria causes low output of uric acid. This condition may eventually lead to slight myopathy in muscle tissue.
Sulfite oxidase is an enzyme responsible for the conversion of some forms of sulfite into inorganic sulfite. Genetic conditions can cause a deficiency in sulfite oxidase that results in the death of the infant around 2–3 years of age. Varying levels of molybdenum in the diet have not been observed causing toxic effects on this level but researchers believe that these genetic conditions are cause by a failure to synthesize the molybdopterin cofactor of these enzymes
==11.8.3 Requirements==
Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. (2001). Retrieved November 28, 2015, from http://www.nal.usda.gov/fnic/DRI/DRI_Vitamin_A/420-441_150.pdf (Links to an external site.) Molybdenum. (2006). Retrieved November 28, 2015, from https://www.nrv.gov.au/sites/default/files/page_pdf/n35-molybdenum_0.pdf (Links to an external site.)
Molybdenum. (2013, December 4). Retrieved November 28, 2015, fromhttp://www.cdc.gov/biomonitoring/Molybdenum_BiomonitoringSummary.html (Links to an external site.)
Novotny, J., & Turnlund, J. (2006, September 29). Molybdenum Intake Influences Molybdenum Kinetics in Men. Retrieved November 28, 2015, from http://jn.nutrition.org/content/137/1/37.full.pdf (Links to an external site.)

## 11.8.4 Imbalance

Deficiencies in molybdenum have only been recorded in humans in a few cases that have not been replicated. In one study two young men with Crohn’s disease had very extensive losses of trace minerals. These participants had symptoms of elevated uric acid levels in their plasma and urine after infusion with molybdenum, consistent with the purpose of xanthine dehydrogenase/oxidase. While this shows that molybdenum is utilized and essential in trace quantities it does not provide researchers any information with which to calculate a minimum dietary recommendation.
Molybdenum toxicity is known as molybdenosis. Some of the most prevalent symptoms in molybdenum toxicity are actually those of copper deficiency because the excess molybdenum interferes with the utilization of copper by the body. Other effects of toxicity are thought to be kidney damage and reproductive abnormalities. Molybdenosis is very rare in humans and most of the research done on intake of the mineral has been conducted in animal studies. Ruminants, specifically, are more sensitive to molybdenum and therefore can be more easily utilized in studies for toxicity but this often is not relevant information when applied to human health. There are many surfacing claims about other health effects of molybdenum but almost all require further investigation. Molybdenum deficiency has been linked to cancer in both the Bantu tribes of Africa and in the Hunan province of China, where naturally low soil levels of the mineral can be found. Studies that which reported that molybdenum may be anticariogenic, or prevent dental caries, were deemed inconclusive but warranted further investigation. There has also been evidence that areas where Keshan’s disease is prevalent also have low levels of molybdenum in the soil and that upon fertilization with the mineral the prevalence decreased.
Chan S, Gerson B, Subramiam S. (1998) The Roke of Copper, Molybdenum, Selenium, and Zinc in nutrition and health. Clinics in Laboratory Medicine. Dec; 18 (4): 673-85
Panel on Micronutrients. (2001) Dietary Reference INtakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. National Academy of Science. Jan 9. pp 420–441.
Rolfes, S Whitney E. (2016). Understanding Nutrition, 14th Edition. Cengage Learning.
WHO (World Health Organization). 1996. Trace Elements in Human Nutrition and Health. Geneva: WHO. pp. 144–154.