Zinc

What is Zinc?

Zinc is an essential mineral needed by hundreds of enzymes. An adult body contains only about 1.5 to 2.5 g, mostly in muscle and bone.^[1]

Its role in the body

• Supports the immune system and helps wounds heal.^[1]
• Needed to make proteins and DNA, and for normal growth in pregnancy, childhood and adolescence.^[1]
• Involved in the sense of taste.^[1]

Important food sources

• Meat, chicken, fish and other seafoodThe richest and best-absorbed sources.
• Eggs, milk, curd and paneer
• Dals, chana, rajma and other legumes
• Nuts, seeds and whole grainsContain zinc, but phytates in plant foods reduce absorption.
• TipSoaking beans, grains and seeds for several hours before cooking can reduce phytates, and fermented foods (such as idli and dosa batter) might improve zinc absorption.

Recommended dietary intake

Signs sometimes associated with low levels

• In children: diarrhoea, slow growth, hair loss, loss of appetite and frequent infections.^[1]
• Zinc deficiency can affect the senses of taste and smell. In older adults, changes in thinking and mood have been reported.^[1]

Why symptoms alone cannot confirm a deficiency

Signs like tiredness, weakness, hair fall or low mood are very common and have many possible causes, such as poor sleep, stress, infections, thyroid problems or other illnesses.

The same sign can come from several different nutrients, or from no nutrient problem at all.

Only a qualified clinician, using your history, an examination and, when needed, lab tests, can say whether a deficiency is present. This app cannot diagnose a deficiency from symptoms or from BMI.

Hair loss, frequent colds and slow healing are common and have many causes.

Tests a clinician might consider

• Blood (serum or plasma) zinc is the usual test, but it has important limits: it changes with age, sex, time of day, recent meals and infection, so results must be interpreted by a clinician.^[1]

Who is more likely to have low intake

• People who follow vegetarian or vegan diets, because zinc from plant foods is absorbed less well.^[1]
• Pregnant and breastfeeding women.^[1]
• People with digestive disorders (such as Crohn’s disease) or after weight-loss surgery.^[1]
• People with alcohol use disorder.^[1]
• Older infants who are only breastfed after 6 months and children with sickle cell disease.^[1]

Potential benefits and quality of evidence

• Zinc is essential for immune function, growth and wound healing.^[1] Established
• Zinc lozenges or syrup started early in a cold may shorten it slightly, but do not make it less severe; results vary between trials.^[1] Limited evidence
• In low-income settings, short-term zinc supplements given by health workers shorten acute diarrhoea in children; this is a medical treatment, not self-care.^[1] Established
• A specific eye-supplement formula containing zinc, copper and antioxidants slows progression of age-related macular degeneration in people at high risk.^[1] Established
• Effects of zinc supplements on type 2 diabetes outcomes are uncertain.^[1] Not enough evidence

Side effects

• Too much zinc can cause nausea, vomiting, stomach upset, loss of appetite, dizziness and headaches.^[1]

Risks of too much

• Taking high doses for weeks can block copper absorption, which may lead to copper deficiency, lower immune function and lower HDL ("good") cholesterol. This is unlikely from food alone.^[1]
• Long-term excessive use of zinc-containing denture creams has caused zinc toxicity.^[1]

Medicine and supplement interactions

• Quinolone and tetracycline antibiotics: Zinc and these antibiotics can reduce each other’s absorption if taken together; timing should follow the doctor’s or pharmacist’s advice.^[1]
• Penicillamine (used for rheumatoid arthritis and Wilson disease): Zinc can reduce its absorption and action.^[1]
• Thiazide diuretics: Increase zinc loss in urine and can lower blood zinc.^[1]
• Iron supplements: Iron supplements can reduce zinc absorption.^[3]

Never start, stop or change a prescribed medicine because of this list — talk to your doctor or pharmacist.

Pregnancy and breastfeeding

• Zinc needs rise in pregnancy and breastfeeding, and deficiency in pregnancy can affect mother and baby. Use supplements only as advised by your doctor; the upper limit still applies.^[1]

Kidney and liver cautions

• No specific kidney or liver limits are given for zinc from food. People with kidney or liver disease should ask their doctor before taking zinc supplements, because their care team may already be monitoring minerals.^[1]

Upper intake limits

When to talk to a professional

Talk to a doctor or registered dietitian before starting a supplement, especially if you are pregnant or breastfeeding, have a long-term illness, or take any regular medicines.

Do not start, stop or change a prescribed medicine because of anything you read here.

Supplements sold without a prescription are not automatically safe. Doses, quality and interactions still matter.

Seek medical care promptly if you have severe, sudden or worsening symptoms.

Still being verified

• ICMR-NIN 2020 values for pregnancy/lactation and Tolerable Upper Limit not verified; not stated.

References

1. NIH Office of Dietary Supplements. Zinc — Fact Sheet for Health Professionals (opens in a new tab) (2026-01-06). Accessed 9 Oct 2026.
2. ICMR-National Institute of Nutrition (India). A Brief Note on Nutrient Requirements for Indians, the Recommended Dietary Allowances (RDA) and the Estimated Average Requirements (EAR), ICMR-NIN, 2020 (opens in a new tab). Accessed 9 Oct 2026.
3. NIH Office of Dietary Supplements. Iron — Fact Sheet for Health Professionals (opens in a new tab) (2025-09-04). Accessed 9 Oct 2026.

Sources checked: 9 Oct 2026