Molybdenum

Nov 07, 2023

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This is a fact sheet intended for health professionals. For a general overview of Molybdenum, see our consumer fact sheet on Molybdenum.

Molybdenum is an essential trace element that is naturally present in many foods and is also available as a dietary supplement. Molybdenum is a structural constituent of molybdopterin, a cofactor synthesized by the body and required for the function of four enzymes: sulfite oxidase, xanthine oxidase, aldehyde oxidase, and mitochondrial amidoxime reducing component (mARC). These enzymes metabolize sulfur-containing amino acids and heterocyclic compounds including purines and pyrimidines [1,2]. Xanthine oxidase, aldehyde oxidase, and mARC are also involved in metabolizing drugs and toxins [3-6].

Molybdenum appears to be absorbed via a passive nonmediated process, though where absorption occurs in the intestinal tract is not known [1]. Adults absorb 40% to 100% of dietary molybdenum [2,7-10]. Infants absorb almost all of the molybdenum in breast milk or formula [11,12].

The kidneys are the main regulators of molybdenum levels in the body and are responsible for its excretion [1,2]. Molybdenum, in the form of molybdopterin, is stored in the liver, kidney, adrenal glands, and bone [2,7,13].

Because molybdenum deficiency is rare [14], molybdenum status is not assessed in clinical settings. According to a small study of 30 healthy men and women, serum levels of molybdenum range from 0.28 ng/mL to 1.17 ng/mL, and their average is 0.58 ng/mL [15]. In another small study of four healthy young men, plasma levels of molybdenum reached 6.22 ng/mL with a molybdenum intake of 1,490 mcg per day for 24 days [10]. The average concentration of urinary molybdenum is 69 ng/mL, but urinary molybdenum does not reflect molybdenum status [1].

Intake recommendations for molybdenum and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board (FNB) at the National Academies of Sciences, Engineering, and Medicine [1]. DRI is the general term for a set of reference values used for planning and assessing nutrient intakes of healthy people. These values, which vary by age and sex, include:

The basis for the EAR for molybdenum consists of two carefully controlled balance studies in a total of eight young men. The EAR for children and adolescents is extrapolated from adult values. Table 1 lists the current RDAs for molybdenum [1].

FoodLegumes are the richest sources of molybdenum [16]. Other foods high in molybdenum include whole grains, nuts, and beef liver [1,14,17,18].

The top sources of molybdenum in U.S. diets are legumes, cereal grains, leafy vegetables, beef liver, and milk [17]. Milk and cheese products are the main sources of molybdenum for teens and children [19].

The amount of molybdenum in food depends on the amount of molybdenum in the soil and in the water used for irrigation [1,2]. Drinking water generally contains only small amounts of molybdenum [17]. However, according to 2017 data from the U.S. Environmental Protection Agency, 0.8% of drinking water samples had molybdenum levels above 40 mcg/L [20]. The U.S. Department of Agriculture’s (USDA’s) FoodData Central [21] does not list the molybdenum content of foods or provide lists of foods containing molybdenum. Therefore, the amount of information on molybdenum levels in foods is quite limited.

*DV = Daily Value. The U.S. Food and Drug Administration (FDA) developed DVs to help consumers compare the nutrient contents of foods and dietary supplements within the context of a total diet. The DV for molybdenum is 45 mcg for adults and children age 4 years and older [22]. FDA does not require food labels to list molybdenum content unless molybdenum has been added to the food. Foods providing 20% or more of the DV are considered to be high sources of a nutrient, but foods providing lower percentages of the DV also contribute to a healthful diet.

Dietary supplementsMolybdenum is available in dietary supplements containing molybdenum only, in combination with other minerals, and in multivitamin/multimineral products. Amounts range from about 50 mcg to 500 mcg. Forms of molybdenum in dietary supplements include molybdenum chloride, sodium molybdate, molybdenum glycinate, and molybdenum amino acid chelate [23]. No studies have compared the relative bioavailability of molybdenum from these different forms.

Most Americans appear to consume adequate amounts of molybdenum. Although national surveys no longer collect data about molybdenum intake, the FDA’s 1984 Total Diet Study estimated that average daily molybdenum intakes from foods were 109 mcg in men and 76 mcg in women [24]. According to the 1988–1994 National Health and Nutrition Examination Survey (NHANES), molybdenum intakes from dietary supplements averaged 23 mcg/day for men and 24 mcg/day for women [25]. Intakes of molybdenum from drinking water collected from the 100 largest cities in the United States are estimated to be about 3 mcg/day based on intakes of 2 liters of water per day [26].

Molybdenum deficiency has not been reported, except in people with a genetic mutation that prevents the synthesis of molybdopterin and therefore of sulfite oxidase [14]. In this rare metabolic disorder, known as molybdenum cofactor deficiency, mutations in one of several genes prevent the biosynthesis of molybdopterin. The absence of molybdopterin impairs the function of enzymes that metabolize sulfite, leading to encephalopathy and seizures [1,14,27-29]; the neurological damage is severe and usually leads to death within days after birth [18,30].

A single reported incident of acquired molybdenum deficiency occurred in 1981 in a patient receiving total parenteral nutrition that was devoid of molybdenum. The patient developed tachycardia, tachypnea, headache, night blindness, and coma. These effects resolved with molybdenum administration [1,31].

No known groups of people are likely to have inadequate molybdenum intakes.

Molybdenum is not a standard treatment for any disease or disorder.

Acute molybdenum toxicity is rare, but it can occur with industrial mining and metalworking exposure. In healthy people, consumption of a diet high in molybdenum usually does not pose a health risk because the molybdenum is rapidly excreted in urine [1,14,18]. One study assessed the effect of high dietary intakes of molybdenum (10–15 mg/day) in an area of Armenia where the soil contains very high levels of molybdenum. The affected individuals experienced achy joints, gout-like symptoms, and abnormally high blood levels of uric acid [14].

Given the absence of human studies, the FNB established ULs for molybdenum for healthy individuals based on levels associated with impaired reproduction and fetal development in rats and mice [1].

* Breast milk, formula, and food should be the only sources of molybdenum for infants.

Molybdenum has no known, clinically relevant, interactions with medications.

The federal government's 2020–2025 Dietary Guidelines for Americans notes that "Because foods provide an array of nutrients and other components that have benefits for health, nutritional needs should be met primarily through foods. ... In some cases, fortified foods and dietary supplements are useful when it is not possible otherwise to meet needs for one or more nutrients (e.g., during specific life stages such as pregnancy)."

For more information about building a healthy dietary pattern, refer to the Dietary Guidelines for Americans and the U.S. Department of Agriculture's MyPlate.

The Dietary Guidelines for Americans describes a healthy dietary pattern as one that:

This fact sheet by the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) provides information that should not take the place of medical advice. We encourage you to talk to your health care providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.

Updated: March 30, 2021 History of changes to this fact sheet