Zinc

mineralzinc atom

Take with food

What is it

Zinc is an essential trace mineral required for immune function, wound healing, protein synthesis, DNA synthesis, and the sense of taste and smell. It is a cofactor for more than 300 enzymes and structural component of many proteins.

How it works

Zinc is absorbed in the small intestine. Once in cells, it serves as a catalytic, structural, or regulatory component of hundreds of zinc-dependent proteins, including immune signaling enzymes, antioxidant enzymes like superoxide dismutase, and transcription factors that regulate gene expression. The body does not have a large zinc storage system, so adequate daily intake matters. Excess intake reduces copper absorption because both compete for the same transporters — chronic high zinc intake causes copper deficiency. Phytate in whole grains and legumes binds zinc and reduces absorption.

Evidence for 6 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Childhood diarrhea (treatment)

Grade A

Strong evidence

Zinc supplementation during acute diarrhea in young children in low-income countries reduces severity and duration. A WHO-recommended intervention.

Common cold (lozenges within 24 hours)

Grade B

Good evidence

Zinc lozenges (zinc gluconate or acetate at doses providing around 75 to 100 mg elemental zinc per day) shorten cold duration by about 1 to 2 days when started within 24 hours of symptom onset. Most trials use frequent lozenges.

Wound healing

Grade B

Good evidence

Zinc supplementation supports healing in people who are deficient. In replete individuals, additional zinc has not clearly accelerated healing.

Age-related macular degeneration progression

Grade B

Good evidence

The AREDS formula (80 mg zinc plus copper, vitamins C, E, and beta-carotene or lutein/zeaxanthin) slowed progression of intermediate AMD. The benefit comes from the combination.

Acne

Grade C

Moderate evidence

Some trials show modest improvement with oral zinc (around 30 mg per day), particularly for inflammatory acne. Effect is smaller than antibiotics or retinoids.

Male fertility

Grade C

Moderate evidence

Zinc supports sperm health; supplementation may improve outcomes in deficient men. In zinc-replete men, additional zinc has not clearly improved fertility.

6 commercial forms

Zinc picolinate

well absorbed, popular general-use form

Bound to picolinic acid. Considered well absorbed and gentle on the stomach. Common in general-purpose zinc supplements.

Zinc gluconate

well absorbed, used in cold lozenges

Common in lozenges for cold treatment and in oral supplements. Inexpensive and effective.

Zinc citrate

similar bioavailability to gluconate

Comparable to gluconate. Common in supplements and may be more palatable in lozenges.

Zinc acetate

preferred form for cold lozenges in trials

Some research suggests zinc acetate lozenges may be most effective for cold duration reduction.

Zinc sulfate

well absorbed, can cause stomach upset

An inexpensive form used in many trials. More likely than other forms to cause nausea.

Zinc oxide

poor oral absorption, mainly topical

Used in sunscreens and diaper creams. Oral absorption is poor compared to other forms.

Dosage

The RDA is 11 mg per day for adult men and 8 mg for women. Pregnant women need 11 mg and breastfeeding women 12 mg. Common supplements provide 15 to 50 mg. The tolerable upper limit is 40 mg per day for adults — chronic intake above this causes copper deficiency and impaired immune function.

When and how to take it

Zinc absorbs best on an empty stomach but commonly causes nausea that way. Most people do better taking it with food, even though absorption is slightly reduced. Avoid taking zinc at the same meal as high-calcium or high-iron supplements, which compete for absorption. For cold treatment, zinc lozenges work best when started within 24 hours of symptom onset and used every 2 to 3 hours while awake. The lozenge must dissolve slowly in the mouth — chewing or swallowing reduces effectiveness.

Food sources

Food	Amount	%DV
Oysters (cooked), 3 oz	32 mg	291%
Beef (chuck roast), 3 oz cooked	7 mg	64%
Crab (Alaskan king), 3 oz cooked	6.5 mg	59%
Pumpkin seeds, 1 oz	2.2 mg	20%
Lobster, 3 oz cooked	3.4 mg	31%
Pork chop, 3 oz cooked	2.9 mg	26%
Baked beans (canned), 1/2 cup	2.9 mg	26%
Cashews, 1 oz	1.6 mg	15%
Cheddar cheese, 1 oz	0.9 mg	8%
Yogurt (plain), 1 cup	1.4 mg	13%

Safety

Acute zinc toxicity from a single high dose causes nausea, vomiting, and stomach cramps. Chronic intake above 40 mg per day causes copper deficiency with anemia, neurological problems, and reduced HDL cholesterol. Long-term high zinc intake can also impair immune function — the very thing it is often taken to support. Zinc lozenges (zinc gluconate or acetate) used for colds can cause nausea and an unpleasant taste; intranasal zinc has been linked to loss of smell and should be avoided.

Who should be cautious

People taking long-term high-dose zinc (above 40 mg/day) should also take 1 to 2 mg of copper to prevent deficiency — this is built into the AREDS eye-vitamin formula. Pregnant women should take prenatal-recommended doses (around 11 mg) rather than higher amounts. People with low copper or anemia of unclear cause should have zinc intake reviewed.

Interactions

Zinc reduces absorption of certain antibiotics (tetracyclines, quinolones) and penicillamine — separate by at least 2 hours. Long-term high zinc intake reduces copper absorption and can cause copper deficiency. Some diuretics increase zinc excretion. Cisplatin and certain other medications can lower zinc levels.

Frequently asked questions

Does zinc shorten colds?⌄

Zinc lozenges started within 24 hours of symptoms can shorten cold duration by 1 to 2 days. Frequency matters — every 2 to 3 hours while awake, dissolved slowly in the mouth.

Can I take zinc every day?⌄

Up to about 40 mg per day for adults from all sources. Chronic intake above that causes copper deficiency.

Should I take zinc with food?⌄

Yes, usually. Zinc on an empty stomach commonly causes nausea. Avoid taking with high-calcium or high-iron supplements at the same meal.

Which form of zinc is best?⌄

For general supplementation, picolinate, gluconate, or citrate are all well absorbed and tolerated. For cold treatment, gluconate or acetate lozenges are best.

Does zinc help testosterone?⌄

Correcting deficiency restores normal testosterone. In men with normal zinc, supplementation has not consistently raised testosterone.

References

NIH ODS Zinc Fact Sheet — NIH Office of Dietary Supplements link

Track Zinc with Pilora

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Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you're pregnant, breastfeeding, on medications, or managing a chronic condition.