Zinc
Essential mineral for immune function, testosterone, and wound healing
Also known as: Zinc Picolinate • Zinc Glycinate • Zinc Citrate
Overview
Zinc is an essential trace mineral involved in over 300 enzymatic reactions in the body. It plays critical roles in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Zinc is also required for proper sense of taste and smell. The body does not store zinc, so daily intake is necessary. An estimated 2 billion people worldwide are zinc deficient, and even mild deficiency can impair immune function, slow wound healing, and reduce testosterone levels in men. Zinc supplementation has been extensively studied for immune support, with meta-analyses showing it can reduce the duration of common colds by 33% when taken within 24 hours of symptom onset.
Key Benefits
Immune System Support
Zinc is essential for the development and function of immune cells including neutrophils, natural killer cells, and T-lymphocytes. Supplementation has been shown to reduce the incidence of infections and reduce cold duration by 33% in meta-analyses.
Testosterone & Reproductive Health
Zinc is required for testosterone synthesis. Studies show that zinc deficiency can reduce testosterone levels by up to 75%. Supplementation in deficient men can significantly increase testosterone, sperm count, and sperm quality.
Skin Health & Wound Healing
Zinc plays a critical role in collagen synthesis, inflammatory response, and cell proliferation — all essential for wound healing. Topical and oral zinc are used to treat acne, with studies showing 30mg zinc gluconate reduces acne lesions by 50%.
Antioxidant Protection
Zinc is a cofactor for superoxide dismutase (SOD), one of the body's most important antioxidant enzymes. It also helps protect cells from oxidative damage and supports the structural integrity of cell membranes.
Dosage & How to Take
The RDA for zinc is 11mg for men and 8mg for women. Supplemental doses of 15–30mg are commonly used for general health, with higher doses (30–50mg) used short-term for immune support during illness.
| Purpose | Dose | Notes |
|---|---|---|
| General health | 15mg/day | Elemental zinc, with food |
| Immune support (acute) | 30–50mg/day | Short-term use (1–2 weeks) during illness |
| Acne treatment | 30mg/day | Zinc gluconate or picolinate, for 2–3 months |
| Testosterone support | 25–30mg/day | Only effective if zinc-deficient |
Best Time to Take
Take with food to reduce nausea. Separate from iron and calcium supplements by at least 2 hours.
With or Without Food
Yes, always take with food. Zinc on an empty stomach commonly causes nausea.
Forms & Bioavailability
| Form | Absorption | Best For | Notes |
|---|---|---|---|
| Zinc Picolinate | High | General supplementation | One of the most bioavailable forms. Well-studied. |
| Zinc Bisglycinate | High | Sensitive stomachs | Chelated form, gentle on the GI tract. |
| Zinc Citrate | Good | Budget option | Good absorption at a lower price point. |
| Zinc Gluconate | Moderate | Lozenges for colds | Most studied form for cold treatment. |
| Zinc Oxide | Low | Avoid for supplementation | Very poor absorption. Common in cheap supplements. |
Side Effects & Safety
Common
- Nausea (especially on empty stomach)
- Metallic taste
- Mild GI discomfort
Rare
- Copper deficiency (with long-term high doses)
- Headache
- Reduced immune function (at very high doses)
Contraindications
- Do not exceed 40mg/day long-term without medical supervision
- Avoid with certain antibiotics (take 2 hours apart)
Interactions
Long-term zinc supplementation (30mg+) can deplete copper. Consider adding 1–2mg copper.
Zinc and iron compete for absorption. Take at different times of day.
High-dose calcium can reduce zinc absorption. Separate by 2 hours.
Zinc can reduce absorption of fluoroquinolone antibiotics. Take 2 hours apart.
Scientific Research
Zinc and Common Cold Duration
Meta-analysis of 13 RCTs found that zinc supplementation within 24 hours of cold onset reduced duration by an average of 33%.
Zinc and Testosterone
Study of zinc-deficient elderly men showed that 6 months of supplementation nearly doubled serum testosterone levels from 8.3 to 16.0 nmol/L.
Zinc and Acne
RCT of 332 patients found 30mg zinc gluconate reduced inflammatory acne lesions by 49.8% after 3 months.
Food Sources
Frequently Asked Questions
Medical Disclaimer
This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.