Zinc
Trace mineralsYour intake
What each level of zinc does
Approximate dose-response bands. Individual response varies — these are starting points, not prescriptions.
- Severely lowYOU ARE HERE0 mg – 3.63 mg
Impaired immune function, taste/smell loss, slow wound healing, hair loss.
- Insufficient3.63 mg – 11 mg
Plant-heavy diets and high-phytate foods reduce absorption.
- Adequate11 mg – 16.5 mg
DV (11 mg) met. Supports 300+ enzymes and immune signaling.
- Therapeutic16.5 mg – 22 mg
Short-term higher doses used for acute immune support and acne.
- High22 mg – 40 mg
Long-term high doses interfere with copper absorption.
- Over upper limit40 mg – +
Above 40 mg/day chronically — copper deficiency and impaired immunity.
Overview
Cofactor for ~300 enzymes and structural component of ~2,000 transcription factors (zinc fingers). Required for immune function, wound healing, growth, taste/smell perception, and male reproductive function. Body has no major storage pool — daily intake matters.
Functions
- ●Catalytic component of carbonic anhydrase, alkaline phosphatase, ~300 enzymes
- ●Structural cofactor in zinc-finger transcription factors (~10% of human proteome)
- ●Required for T-cell development and macrophage function
- ●Cofactor in superoxide dismutase (antioxidant)
- ●Required for wound healing, taste/smell, sperm motility
Mechanism
Zinc binds catalytic sites of metalloenzymes (carbonic anhydrase, MMPs, alcohol dehydrogenase) where it activates water for nucleophilic attack. Zinc fingers fold around bound zinc to recognise specific DNA sequences — disrupting this disrupts gene expression broadly. In the immune system, zinc is required for thymulin activation and thymocyte proliferation.
Benefits
- ●Reduces common cold duration ~33% when started <24 h of onset (lozenges, 75+ mg/day)
- ●Treats and prevents acrodermatitis enteropathica
- ●Reduces diarrhea duration in children (WHO ORS + zinc protocol)
- ●Slows AMD progression (AREDS formula)
- ●Improves wound healing in deficient adults
Deficiency
Mild zinc deficiency is common in low-meat diets and in regions where phytate-rich grains dominate. Severe deficiency is rare but acrodermatitis-like presentations occur.
- ●Impaired wound healing
- ●Loss of taste and smell (anosmia, hypogeusia)
- ●Diarrhea, alopecia
- ●Impaired immunity, recurrent infections
- ●Growth retardation in children
- ●Hypogonadism, infertility
- ●Acrodermatitis-like rash (perioral, perineal)
- ●Vegetarians/vegans (low intake + high phytate)
- ●GI disorders (Crohn's, celiac)
- ●Alcohol use disorder
- ●Chronic diuretic therapy
- ●Sickle cell disease
- ●Pregnancy, lactation
Excess
Chronic intake >40 mg/day causes copper deficiency anemia and neutropenia. Acute high doses cause GI distress; intranasal zinc was associated with anosmia and removed from market.
- ●Nausea, vomiting, GI distress (acute)
- ●Copper deficiency, myelopathy (chronic; 'zinc-induced copper deficiency')
- ●Reduced HDL cholesterol
- ●Impaired immune function (paradoxical at high doses)
- ●Anosmia from intranasal gel (banned)
Forms
- Zinc bisglycinate (chelated)Well-absorbed, gentle; best general-purpose
- Zinc picolinateWell-absorbed; some prefer for limited GI distress
- Zinc citrateWell-absorbed, neutral taste
- Zinc gluconate / acetate lozengesThe form for cold-shortening at 75+ mg/day for 3-5 days
- Zinc oxideCheap, low bioavailability; topical (sunscreen, diaper cream)
- Zinc sulfateCheap; ORS protocol; GI distress at higher doses
Food sources
- Oysters (cooked) · 3 oz75 mg
- Beef (cooked) · 3 oz7 mg
- Crab (cooked) · 3 oz6.5 mg
- Pumpkin seeds · 1 oz2 mg
- Cashews · 1 oz1.6 mg
- Chickpeas (cooked) · 1 cup2.5 mg
Supplement forms
Zinc bisglycinate, picolinate, and citrate are well-absorbed. Avoid zinc oxide as the primary form — bioavailability is low. Don't run high doses (>40 mg) for more than a few weeks without paired copper or lab monitoring. For immune support during a cold, zinc acetate or gluconate lozenges are the best-supported delivery.
Bioavailability
~30% from mixed diet. Animal protein and citric acid enhance absorption; phytate inhibits it (vegan absorption ~10–15%). Soaking, sprouting, and leavening reduce phytate. Take separated from iron and calcium by 2 hours. High-dose zinc transiently saturates metallothionein, crowding out copper absorption.
Longevity relevance
Adequacy supports immune function and antioxidant defence — both increasingly compromised with age. Older adults are commonly subclinically deficient. The zinc-copper ratio matters: chronic high-dose zinc without paired copper drives anemia and neurological decline.
Relationships
- Vitamin A · Zinc required for RBP synthesis; low zinc looks like vit A deficiency
- Vitamin C, vitamin E · Antioxidant cooperation; AREDS formula combines all four with copper
- Protein (animal source) · Improves zinc bioavailability ~2×
- Copper · Bidirectional competition; high zinc depletes copper and vice versa
- Iron, calcium (high dose) · Compete for DMT1 transporter; separate by 2 hours
- Phytate (whole grains, legumes) · Reduces absorption substantially; soak/sprout/leaven to mitigate
- Fluoroquinolones, tetracyclines · Chelated by zinc; separate dosing by 4 hours
References
About Zinc
100+ enzymes; immune function, wound healing, DNA synthesis.
- Role
- Immune · enzymes
- Daily target
- 11 mg (DV)
- Upper limit
- 40 mg
- Also called
- zinc, zinc citrate, zinc gluconate, zinc picolinate, zinc bisglycinate, zinc oxide
Forms with lower absorption: oxide. Prefer better-absorbed forms when supplementing.
The mechanisms and systems this nutrient feeds. Click any to drill into what runs on it.
★ = load-bearing / primary cofactor. Track these in My Journey.
Top food sources of Zinc
Whole foods that contribute meaningfully (≥10% DV per 100 g serving). Click any food to see its full nutrient profile and what else it brings to the table.