Zinc Glycinate: Uses, Benefits, Dosage & Safety
Last updated: August 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy
Quick summary
Zinc glycinate (bisglycinate) is zinc chelated to glycine, which improves absorption and markedly reduces the nausea that zinc commonly causes. It is a good default form for anyone who has struggled with zinc on an empty stomach.
What is Zinc Glycinate?
Zinc bound to two glycine molecules in a chelate. The chelation protects the zinc through the stomach and allows absorption via amino acid transport routes rather than competing with other minerals. Elemental zinc content is around 20%.
What Zinc Glycinate is commonly used for
Correcting zinc deficiency, immune support, skin conditions including acne, taste and smell disturbance, and male reproductive health.
How Zinc Glycinate works
Zinc is a cofactor for over 300 enzymes and required for immune cell function, wound healing, protein synthesis and DNA repair. Deficiency impairs immunity, taste and wound healing. The glycinate form changes absorption and tolerability, not what the zinc then does.
What the evidence says
Each claim below is tied to the specific study behind it, rather than to a general reading list.
- Chelated zinc forms show improved bioavailability over zinc oxide. Gandia et al., International Journal for Vitamin and Nutrition Research, 2007 — comparative absorption study. (PubMed)
- Zinc supplementation reduces duration of the common cold. Hemilä, JRSM Open, 2017 — meta-analysis of zinc lozenge trials. (PubMed)
- High-dose zinc induces copper deficiency. Willis et al., American Journal of Clinical Pathology, 2005 — case series and review. (PubMed)
Typical dosage used in studies
8–11 mg daily meets requirements; supplemental doses of 15–30 mg elemental are common. The tolerable upper limit is 40 mg daily from all sources. Read the elemental figure, not the compound weight.
Side effects and safety
Better tolerated than zinc sulphate or oxide, with much less nausea. The important long-term issue is copper: zinc above roughly 40 mg daily sustained depletes copper and can cause anaemia and neurological problems. Quality products include a small amount of copper for this reason.
Medication interactions and who should avoid Zinc Glycinate
Medication & safety check
Zinc reduces absorption of quinolone and tetracycline antibiotics, bisphosphonates and penicillamine — separate by at least two hours. Long-term high-dose zinc requires copper. Thiazide diuretics increase zinc loss.
General information, not personal medical advice. If you take any medication, confirm it is safe to combine with Zinc Glycinate with your doctor or pharmacist first.
Sources & further reading
The claim-level citations above are drawn from these sources:
- Gandia et al., International Journal for Vitamin and Nutrition Research, 2007 — comparative absorption study — find on PubMed
- Hemilä, JRSM Open, 2017 — meta-analysis of zinc lozenge trials — find on PubMed
- Willis et al., American Journal of Clinical Pathology, 2005 — case series and review — find on PubMed
- NIH Office of Dietary Supplements
- NIH National Center for Complementary and Integrative Health
Frequently asked questions
Why does zinc make me nauseous?
Zinc irritates the gastric lining, particularly on an empty stomach and particularly as sulphate or oxide. Glycinate is much gentler; taking it with food helps regardless.
Do I need copper with it?
At sustained doses above roughly 40 mg daily, yes. At 15–25 mg it is less critical but a small amount of copper is sensible insurance.
Glycinate or picolinate?
Both are well absorbed and well tolerated. The differences between them are small compared with the difference from oxide.
Part of a wider guide
Zinc Glycinate is one form of Zinc. This page covers what is specific to this form — absorption, tolerability, dosing and who it suits. For the underlying nutrient itself, its overall evidence base and general safety, read the Zinc guide.
Where you'll find Zinc Glycinate
Zinc Glycinate appears in Minerals formulas. Browse the supplement guides to see the products we review, each with a full breakdown of formula, pricing and safety.
Related ingredients to explore
Ingredients often studied or formulated alongside Zinc Glycinate.
General information, not medical advice.