Molybdenum

A trace mineral four enzymes need to break down sulfur-containing amino acids, purines and some drugs and toxins. Legumes are the richest sources.

How much you need

The official Recommended Dietary Allowance for adults, per day:

Age	Men	Women	Pregnancy	Breastfeeding
19–50 years	45 mcg	45 mcg	50 mcg	50 mcg
51–70 years	45 mcg	45 mcg	—	—
Over 70	45 mcg	45 mcg	—	—

The requirement rests on two carefully controlled studies in a total of eight young men.

People aged 18 fall in the official 14–18 group — 43 mcg a day, and 50 mcg in pregnancy and when breastfeeding. Its upper limit is 1,700 mcg. Pregnancy and breastfeeding change what you need — confirm yours with your midwife, obstetrician or doctor.

Upper limit

Age	Men	Women	Pregnancy	Breastfeeding
19–50 years	2,000 mcg	2,000 mcg	2,000 mcg	2,000 mcg
51–70 years	2,000 mcg	2,000 mcg	—	—
Over 70	2,000 mcg	2,000 mcg	—	—

The upper limit is the most molybdenum a day that is unlikely to cause harm, not a target. With no human studies to go on, it was based on harm to reproduction and fetal development in rats and mice. The fact sheet does not say whether it covers food as well as supplements; in healthy people, a diet high in molybdenum usually poses no risk, because the excess is quickly excreted.

What it does

Molybdenum is part of molybdopterin, a cofactor for four enzymes that break down sulfur-containing amino acids and compounds including purines and pyrimidines; three of them also help metabolise drugs and toxins ^[1]. Adults absorb 40% to 100% of the molybdenum in food, and the kidneys regulate how much the body keeps ^[1].

Forms

Supplements contain molybdenum chloride, sodium molybdate, molybdenum glycinate or amino acid chelates, in amounts from about 50 to 500 mcg; no studies have compared how well they are absorbed ^[1].

Where it comes from

Black-eyed peas, boiled½ cup288 mcg
Beef liver, pan fried3 ounces104 mcg
Lima beans, boiled½ cup104 mcg
Yogurt, plain, low-fat1 cup26 mcg
Milk, 2% milkfat1 cup22 mcg

How these five were chosen: The five foods with the most molybdenum per serving in the NIH fact sheet's food table. Fortified foods are marked.

How far one serving goes toward a day's molybdenum

How far one serving goes toward a day's molybdenum
Item	Percent of the adult daily amount (45 mcg)
Black-eyed peas	640%
Beef liver	231%
Lima beans	231%
Yogurt, low fat	58%
Milk, 2%	49%

Against the recommended daily amount for adults 19 to 50: 45 mcg. Where a food varies by brand, the bar shows the lowest figure and the label the full range. Computed from the figures on this page, taken from the NIH fact sheet.

Getting the most from it

The molybdenum in food depends on the soil and irrigation water where it was grown ^[1]. Legumes, cereal grains, leafy vegetables, beef liver and milk are the top sources in U.S. diets ^[1]. Food composition data are limited: the USDA database does not list molybdenum ^[1].

In the United States

Most Americans appear to get enough molybdenum ^[1]. The FDA's 1984 Total Diet Study estimated average intakes from food of 109 mcg a day for men and 76 mcg for women, and in 1988–1994 supplements added an average of 23 to 24 mcg ^[1].

Who is most likely to run low

No groups of people are known to be likely to have inadequate molybdenum intakes ^[1]

What deficiency looks like

Molybdenum deficiency has not been reported, except in people with a rare genetic disorder that stops the body making molybdopterin, which causes severe brain damage and usually death within days of birth ^[1]. One case of acquired deficiency occurred in 1981 in a patient on intravenous feeding without molybdenum ^[1].

What the evidence supports, and what it doesn't

Established. Molybdenum is essential for four enzymes that metabolise sulfur-containing amino acids and other compounds ^[1].

Not supported by trials. Molybdenum is not a standard treatment for any disease or disorder ^[1].

Too much

In healthy people, a diet high in molybdenum usually poses no risk, because the excess is quickly excreted in urine ^[1]. In an area of Armenia with very high soil molybdenum, people eating 10 to 15 mg a day had aching joints, gout-like symptoms and high blood uric acid ^[1]. Acute toxicity is rare and comes from mining and metalworking exposure ^[1].

Medicines that interact

Molybdenum has no known clinically relevant interactions with medicines ^[1]. If you take medicines regularly, your doctor or pharmacist can still tell you whether any supplement suits you.