Zinc

Zinc is needed in small but constant amounts. It sits at the active site of hundreds of enzymes, including the ones that make new DNA, the ones that build proteins, and the ones that help immune cells respond to threats. It plays a particular role in skin healing (which is why mild zinc-low states are sometimes flagged by poor wound healing) and in taste and smell (mild low zinc can dull both).

The body stores very little zinc in a quickly-mobilised pool, so daily intake matters. Absorption is regulated: when intake is high, less is absorbed; when intake is low, the body holds on to more. Phytate, a compound in unrefined wholegrains and pulses, binds zinc and reduces absorption. Soaking, fermenting (sourdough), or sprouting pulses and grains reduces phytate; eating zinc-rich animal foods bypasses the issue.

Vegetarian and vegan zinc: meeting the target is doable but the pattern matters. Pulses, nuts, seeds, wholegrains, tofu, and dairy or fortified plant alternatives are the building blocks. Sourdough bread instead of standard yeasted, soaked or sprouted pulses, and a good variety of nuts and seeds across the week all help.

Zinc and iron: the two minerals share a transport mechanism in the gut, which is why a high-dose iron supplement taken with a zinc-containing meal can reduce zinc absorbed. The doses people get from food are not a problem; the interaction is mainly a consideration during therapeutic iron supplementation.

Zinc is found across animal foods, pulses, nuts, seeds, wholegrains, and dairy. Values per 100g come from USDA SR Legacy and McCance and Widdowson 7th edition; the site's food entries currently store macros only.

Practical: a portion of beef or other red meat a few times a week, or a daily handful of pulses, nuts, or seeds, plus dairy or eggs, comfortably covers the zinc reference for most adults. Vegans can hit it with chickpeas, lentils, tofu, cashews, pumpkin seeds, and wholegrains across the week.

Oysters: the highest natural zinc source by a wide margin, but not a daily food for most UK shoppers. A monthly portion goes a long way.

UK Reference Nutrient Intake (RNI) for zinc is set by SACN (1991 Dietary Reference Values).

Severe zinc deficiency is uncommon in healthy UK adults eating a varied diet. Milder low intakes show themselves as:

• Slow wound healing
• Reduced sense of taste or smell
• Hair loss
• Diarrhoea
• Skin rashes or eczema-like changes
• More frequent infections
• Loss of appetite
• In children: slow growth, delayed sexual development

Who is at higher risk in the UK

• Vegans and vegetarians with narrow diets. Plant zinc absorption is lower because of phytate binding. Variety in pulses, nuts, seeds, and wholegrains, and choosing sourdough or sprouted forms where possible, helps.
• People with malabsorption conditions: coeliac disease, Crohn's, ulcerative colitis, after bariatric surgery.
• Heavy alcohol use. Reduces absorption and increases urinary losses.
• People taking long-term high-dose iron supplements (which compete for absorption). Discuss timing with the prescriber.
• Older adults with reduced food intake or chewing difficulties.
• People on long-term diuretics can lose more zinc in urine.
• Children in deprived settings globally, though severe child zinc deficiency is rare in the UK.

If symptoms or a risk factor are present, a GP can arrange a blood test. Note that serum zinc is an imperfect indicator (most body zinc sits in tissues, not blood), and persistent symptoms in a risk group can warrant a dietary trial even with a normal blood result.

Zinc from food is not a realistic concern. The risk is from supplements at high doses.

NHS supplement guidance: taking 25mg or less a day of zinc from supplements is unlikely to cause harm.

Higher doses can cause:

• Nausea, vomiting
• Loss of appetite
• Stomach cramps, diarrhoea
• Headache

Very high long-term doses (above 50mg/day) interfere with copper absorption and can cause copper deficiency, which leads in turn to its own anaemia and nerve problems. Zinc lozenges used for colds (typically 13 to 23mg per lozenge) should not be taken at full dose continuously for more than a few days.

Most UK adults eating a varied diet meet the zinc target from food. Targeted supplementation is used in specific situations.

When a zinc supplement may be sensible (ideally with GP or dietitian advice):

• Confirmed deficiency on blood test plus symptoms.
• Some absorption conditions on personalised advice.
• Vegans whose diet is particularly low in pulses, nuts, seeds, and wholegrains.
• Short courses for the duration of certain illnesses, on medical advice.

Practical pointers:

• Take a zinc supplement away from high-dose iron supplements: separate by a few hours, or take with different meals.
• Take with food if the supplement causes nausea.
• Stay at or below 25mg per day of supplemental zinc unless directed by a clinician.

For vegans: the practical route to enough zinc is variety. Across a week: chickpeas, lentils, tofu, cashews, pumpkin seeds, hemp seeds, wholegrain oats or sourdough wholegrain bread. A modest zinc supplement (e.g. 5 to 10mg/day) is a reasonable backstop for anyone whose diet is genuinely narrow.

• Iron and zinc share absorption pathways: Iron. The detail matters when iron supplements are involved.
• Vegan zinc and other minerals: Plant-based eating.
• Best food sources: Oyster, Beef, Chickpeas, Lentils, Cashew nuts, Cheddar.

• NHS. Vitamins and minerals: Others. nhs.uk/conditions/vitamins-and-minerals/others. Adult RNI and supplement guidance for zinc.
• SACN. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. Department of Health Report 41 (1991). Source of the age-banded RNIs.
• Public Health England. McCance and Widdowson's The Composition of Foods, 7th summary edition (2015).
• USDA Agricultural Research Service. FoodData Central, SR Legacy release. fdc.nal.usda.gov.

This page is reference information for UK shoppers. It is not medical advice.