SYS ONLINE
SUPPLEMENT_SCHOLAR
evidence · mechanism · dose
Supplements/Mineral

Zinc

Cofactor for ~300 enzymes — critical for testosterone, immune function, and DNA synthesis.

Testosterone SupportImmune FunctionMen's HealthSkin, Hair & NailsGeneral Wellness

Overview

An essential trace mineral required for catalytic, structural, and regulatory functions across nearly every cell type.

Natural sources
  • Oysters (richest source)
  • Beef
  • Pumpkin seeds
  • Cashews
  • Lentils
Common forms
  • Picolinate
  • Bisglycinate
  • Citrate
  • Gluconate (lozenges)
  • Oxide (poor absorption)

Forms & variants of Zinc

Different chemical forms of Zinc behave differently. Browse each form's mechanism, bioavailability, and best-use context.

Picolinate
Zinc Picolinate

Zinc chelated to picolinic acid — one of the most bioavailable oral forms.

Bisglycinate
Zinc Bisglycinate

Glycine-chelated zinc — high absorption and very gentle on the stomach.

Acetate (lozenges)
Zinc Acetate

Lozenge form shown to shorten cold duration when used at first symptoms.

Gluconate
Zinc Gluconate

Most common over-the-counter zinc form — affordable, moderate bioavailability.

Bisglycinate
Zinc Bisglycinate (High-Bio)

Chelated zinc with superior absorption and tolerability.

Mechanism of action

Zinc serves as a catalytic cofactor (e.g. carbonic anhydrase), structural element in zinc-finger transcription factors, and immune signaling regulator.

Pathways
  • · Testosterone biosynthesis
  • · Thymulin activation (immune)
  • · Zinc-finger transcription
Hormones
  • · Testosterone (supports in deficiency)
  • · Insulin (cofactor)
Enzymes
  • · Carbonic anhydrase
  • · Alcohol dehydrogenase
  • · DNA polymerase

Effects on the body

Supports
Testosterone synthesis (in deficiency)
Supports
Immune function
Decreases
Cold duration (lozenges)
Supports
Wound healing

Organ system effects

Immune System

Required for T-cell development; lozenges shorten cold duration.

Endocrine

Restoring deficiency raises testosterone; supraphysiologic doses don't add benefit.

Reproductive

Concentrated in prostate; supports sperm quality.

Evidence-based benefits

Reduces duration of common cold (lozenges within 24h of onset)

Moderate evidence

Restores testosterone in deficient men

Moderate evidence

Improves acne severity

Moderate evidence

Potential side effects

Common
  • · Nausea on empty stomach
  • · Metallic taste (lozenges)
Rare
  • · Headache
Serious
  • · Copper deficiency / anemia with chronic high-dose use (>40 mg/day)

Drug interactions

Fluoroquinolone & tetracycline antibiotics
Reduces absorption — separate by 2+ hours.
moderate
Penicillamine
Mutually reduced absorption.
moderate
Thiazide diuretics
May increase zinc excretion.
minor

Safety & non-supplemental interactions

Educational summary — always confirm with your clinician or pharmacist before starting, stopping, or combining with prescription therapy.

Avoid with these conditions
  • ·Hormone-sensitive cancers (breast, prostate, ovarian, uterine)
  • ·Autoimmune disease (theoretical immune activation)
Avoid / monitor with these medications
  • ·Hormonal contraceptives, HRT, tamoxifen, aromatase inhibitors
  • ·Immunosuppressants
  • ·Tetracyclines, fluoroquinolones (chelation — 2 h apart)
  • ·Penicillamine
  • ·Thiazide diuretics (raise zinc loss)
Other notes
  • ·Chronic >40 mg/day depletes copper — pair with copper if used long-term.

Supplement interactions

Pairs well with
  • Copper (1–2 mg per 15 mg zinc)
    Prevents zinc-induced copper deficiency on long-term use.
  • Magnesium + Vitamin B6 (ZMA)
    Classic recovery/sleep stack.
Avoid combining with
  • Calcium / iron (same dose)
    Mineral competition for absorption.
  • Long-term zinc without copper
    Risk of copper-deficiency anemia.

Dosing & bioavailability

Typical dose
15–30 mg elemental
Beginner dose
8–11 mg (RDA)
Study range
15–50 mg
Upper safe limit
40 mg/day (IOM UL)
Best form
Picolinate or bisglycinate
Timing
With a meal (not on empty stomach)
With food?
With food — but separate from high-iron/calcium meals

Where to buy

Affiliate-style search links to reputable retailers. We don't endorse specific brands — verify third-party testing (USP, NSF, Informed Sport) before purchase.

Mineral
Zinc
Amazon
Wide selection · fast shipping
Mineral
Zinc
iHerb
Global delivery · curated brands
Mineral
Zinc
Thorne
Practitioner-grade · NSF tested

Scientific evidence (10)

Meta-analysisJRSM Open · 2017

Zinc lozenges and the common cold

Hemilä H

Meta-analysis of 7 RCTs of zinc acetate/gluconate lozenges ≥75 mg/day.

Key findings

Cold duration reduced by ~33% when started within 24 h of symptom onset.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — Reduces duration of common cold

Live PubMed search

Live results for "Zinc Reduces duration of common cold" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "Reduces duration of common cold". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — Restores testosterone in deficient men

Live PubMed search

Live results for "Zinc Restores testosterone in deficient men" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "Restores testosterone in deficient men". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — Improves acne severity

Live PubMed search

Live results for "Zinc Improves acne severity" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "Improves acne severity". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — randomized controlled trial

Live PubMed search

Live results for "Zinc randomized controlled trial" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — meta-analysis

Live PubMed search

Live results for "Zinc meta-analysis" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — pharmacokinetics

Live PubMed search

Live results for "Zinc pharmacokinetics" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "pharmacokinetics". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — safety adverse events

Live PubMed search

Live results for "Zinc safety adverse events" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "safety adverse events". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewPubMed (NLM) · 1970

PubMed: Zinc — dose response

Live PubMed search

Live results for "Zinc dose response" across the PubMed/MEDLINE peer-reviewed index.

Key findings

Opens current human and preclinical literature matching Zinc and "dose response". Filter by RCT, meta-analysis, or year on the results page.

Open study
Systematic reviewGoogle Scholar · 1970

Google Scholar: Zinc — clinical evidence

Live Scholar search

Cross-database citation index for Zinc as it relates to "clinical evidence".

Key findings

Includes preprints, theses, and journal articles. Useful for tracking citation counts and follow-on work.

Open study
Educational use only. This profile is not medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you take prescription medication or have a chronic condition.