Zinc
A mineral that hundreds of enzymes need, involved in immune function, protein and DNA synthesis, wound healing and the sense of taste. Oysters and beef are rich sources.
8 mg women
How much you need
The official Recommended Dietary Allowance for adults, per day:
| Age | Men | Women | Pregnancy | Breastfeeding |
|---|---|---|---|---|
| 19–50 years | 11 mg | 8 mg | 11 mg | 12 mg |
| 51–70 years | 11 mg | 8 mg | — | — |
| Over 70 | 11 mg | 8 mg | — | — |
People aged 18 fall in the official 14–18 group — 11 mg a day for males and 9 mg for females, 12 mg in pregnancy and 13 mg when breastfeeding. Its upper limit is 34 mg. 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 | 40 mg | 40 mg | 40 mg | 40 mg |
| 51–70 years | 40 mg | 40 mg | — | — |
| Over 70 | 40 mg | 40 mg | — | — |
The upper limit covers zinc from food and supplements combined. It is the most that is unlikely to cause harm, not a target, and was set from the amount that harms copper status. It does not apply to people taking zinc as medical treatment, who should be under a doctor's care — the AREDS formula the National Eye Institute recommends for macular degeneration contains 80 mg, twice the limit.
What it does
Zinc is needed for the activity of hundreds of enzymes and plays a role in immune function, making protein and DNA, wound healing, and cell signalling and division [1]. It supports growth and development during pregnancy, infancy, childhood and adolescence, and is involved in the sense of taste [1]. The body holds about 1.5 g in women and 2.5 g in men, mostly in muscle and bone [1].
Forms
Supplements contain zinc sulfate, acetate, gluconate and other forms, and the label states the amount of elemental zinc, not the weight of the whole compound [1]. About 61% of the zinc in citrate or gluconate is absorbed in young adults, and 50% from zinc oxide [1]. Zinc is also in some cold lozenges, nasal sprays, homeopathic products and denture adhesive creams [1].
Where it comes from
- Oysters, Eastern, farmed, raw3 ounces32 mg
- Oysters, Pacific, cooked3 ounces28.2 mg
- Beef, bottom sirloin, roasted3 ounces3.8 mg
- Blue crab, cooked3 ounces3.2 mg
- Breakfast cereals, fortified with 25% of the Daily Value for zincfortified1 serving2.8 mg
How these five were chosen: The five foods with the most zinc per serving in the NIH fact sheet's food table. Fortified foods are marked.
| Item | Percent of the adult daily amount (11 mg) |
|---|---|
| Oysters, Eastern, raw | 291% |
| Oysters, Pacific | 256% |
| Beef sirloin | 35% |
| Blue crab | 29% |
| Breakfast cereal | 25% |
Getting the most from it
The body absorbs from 5% to more than 50% of the zinc in food, depending on how much of the diet is plant-based [1]. Beans, nuts and whole grains contain phytates, which bind zinc and block its absorption; soaking beans, grains and seeds for several hours before cooking reduces this, and fermented foods might help [1]. Taking an iron supplement of 25 mg or more at the same time as zinc can reduce zinc absorption, although the iron in fortified foods does not [1].
In the United States
Most Americans get enough zinc, although older adults may have marginal intakes [1]. Average intake from food is 13 mg a day for men and 9.2 mg for women, and 16.4 mg and 12.6 mg including supplements [1]. Even so, in 2005–2016 data, 15% of adults took in less than the average requirement [1]. Oysters contain more zinc per serving than any other food, but beef provides 20% of the zinc Americans eat because it is so common, and fortified breakfast cereals are a major source [1].
Who is most likely to run low
- People with inflammatory bowel disease — 15% to 40% are zinc deficient — and people with celiac disease or who have had bariatric surgery [1]
- People who follow vegetarian or vegan diets, whose phytate-rich foods make zinc harder to absorb [1]
- Pregnant and breastfeeding women, whose requirement rises by 3 and 4 mg a day [1]
- People with alcohol use disorder — low zinc status is found in 30% to 50% [1]
What deficiency looks like
Zinc deficiency affects many tissues, including the skin, bones, and the digestive, reproductive, nervous and immune systems [1]. In children it causes diarrhea, hair loss, delayed growth and frequent infections; it can also dull taste and smell, and in older adults delay wound healing and change thinking and mood [1]. In populations with little absorbable zinc, deficiency in pregnancy increases the risk of premature birth, low birth weight and other adverse outcomes [1]. Serum zinc below 70 mcg/dL in women or 74 mcg/dL in men indicates inadequate status, although the test has important limitations [1].
What the evidence supports, and what it doesn't
Established. Zinc is essential for hundreds of enzymes, immune function and growth [1]. In AREDS, 4,757 people aged 50 to 80 at high risk of advanced macular degeneration who took a daily formula of 80 mg zinc with copper, beta- carotene and vitamins C and E for 5 years had a 25% lower risk of advanced disease than those on placebo, and AREDS2 confirmed the benefit [1]. The fact sheet advises people with or developing macular degeneration to talk to their health care provider about these formulations [1].
Not supported by trials. Preventing colds: a 2024 Cochrane review of 34 trials in 8,526 people found that zinc makes little or no difference to the chance of catching a cold [1]. Type 2 diabetes: the fact sheet finds the evidence insufficient to support any conclusion about zinc supplements and diabetes [1].
Mixed. Treating colds: the same review found that zinc, mostly as lozenges, may shorten a cold by about 2 days, with an unclear effect on how bad the symptoms are — all on low to very low certainty evidence [1]. Childhood diarrhea: in low-income countries, where deficiency is common, zinc shortens acute diarrhea, but the effect may be marginal in well-nourished children [1].
Too much
High intakes can cause nausea, dizziness, headaches, stomach upset, vomiting and loss of appetite [1]. Taken for weeks, 50 mg a day or more — usually from supplements or overuse of zinc-containing denture creams — can block copper absorption and cause low copper status, reduce immune function and lower HDL cholesterol [1]. Food rarely provides as much as 50 mg, so the zinc in food is unlikely to cause toxicity [1]. Chronic overuse of denture creams containing zinc has caused nerve damage and anemia; zinc-free creams are available [1].
Medicines that interact
Quinolone antibiotics such as ciprofloxacin and tetracycline antibiotics can bind zinc in the gut, reducing the absorption of both; taking the antibiotic at least 2 hours before or 4 to 6 hours after the zinc supplement minimises this [1]. Zinc reduces the absorption and action of penicillamine, used for rheumatoid arthritis and Wilson disease, so the two should be taken at least 1 hour apart [1]. Thiazide diuretics such as hydrochlorothiazide increase zinc loss in urine [1]. If you take any of these regularly, talk to your doctor or pharmacist before taking a zinc supplement.
References
- NIH Office of Dietary Supplements. Zinc — Fact Sheet for Health Professionals. Updated 6 January 2026. ods.od.nih.gov
How we reviewed this page
Every value on this page comes from the NIH Office of Dietary Supplements — Zinc, Health Professional Fact Sheet, which presents the official U.S. intake recommendations set by the National Academies. The source was last updated on January 6, 2026, and this page was checked against it on October 18, 2026. Numbered markers link to the source for each claim, so you can check the original rather than take our word for it.
Drafted with AI assistance, then edited and fact-checked by a human. No value is published on the strength of a model's recall.
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General information only. This is not medical advice.