Zinc
Immune support, wound healing, and a dozen other things the body quietly relies on.
Zinc is involved in immune defence, skin repair, testosterone regulation, and the activity of over 300 enzymes. The body does not store zinc, so consistent daily intake matters more than occasional high doses. Zinc picolinate and zinc citrate are better absorbed than zinc oxide, which is the cheapest and most common form in supplements. One important caveat: high-dose zinc supplementation over time can deplete copper, because the two minerals compete for the same absorption transporter in the gut.
Reference values
Daily reference values from official nutrition authorities. These are population reference figures, not personal recommendations.
| RDA | Upper limit | Source |
|---|---|---|
| 7 mg | 25 mg | UK |
Forms and bioavailability
Not all forms are absorbed equally. The form on your supplement label affects how much your body can actually use.
| Form | Absorption | With food | Timing | Evidence |
|---|---|---|---|---|
| zinc gluconate | Typical | With food | Either | Strong |
| zinc citrate | Typical | With food | Either | Likely |
| zinc picolinate | Higher | With food | Either | Possible |
| zinc bisglycinate (chelate) | Higher | With food | Either | Likely |
How it pairs with other supplements
Things to watch for
Zinc and copper compete for intestinal absorption; sustained high zinc (>40 mg/day) induces metallothionein and depletes copper. Aim for ~10-15 mg zinc per 1 mg copper when supplementing.
Iron and zinc share intestinal divalent-metal transporters; high-dose supplementation of either can modestly reduce uptake of the other. Spacing by a meal or supplementing on different days mitigates the effect.
High-dose calcium (>600 mg per meal) modestly reduces zinc absorption. Lower-dose calcium intake from food does not show a meaningful effect.
Stack Almanac monitors your zinc-to-copper ratio when you are taking both and flags when zinc intake looks high relative to copper, to help you avoid inadvertently creating an imbalance over time.
Track your Zinc in Stack Almanac
Last reviewed: 2026-05-21. Reference values are adult-general RDAs from UK. Individual needs may vary. This page is for informational purposes only and is not a substitute for professional medical advice.