What are the ingredients in zinc bisglycinate supplements?

January 8, 2026 •

4 min read

Studies have shown that chelated zinc bisglycinate offers superior absorption compared to other zinc forms, with some indicating up to 43% higher blood levels than zinc gluconate. This effectiveness comes down to its unique chemical composition, which combines a key mineral with a foundational amino acid to improve the body's uptake and utilization.

Quick Summary

Zinc bisglycinate supplements are primarily composed of zinc chelated with two glycine molecules, which improves absorption and digestive tolerance. Supplements also contain inactive ingredients like capsules, fillers, and anti-caking agents, which can vary between brands. The combination of zinc and glycine creates a stable, bioavailable compound that the body efficiently absorbs. Some products may include additional vitamins like B6 to enhance functionality.

Key Points

Core Components: Zinc bisglycinate is a chelated mineral, combining a zinc ion with two molecules of the amino acid glycine to enhance absorption.
Bioavailability: The chelation process protects zinc from dietary inhibitors, allowing for superior absorption compared to inorganic zinc forms like gluconate.
Digestive Tolerance: This form is notably gentle on the stomach, significantly reducing the likelihood of gastrointestinal side effects such as nausea.
Additional Ingredients: Commercial supplements contain inactive ingredients like cellulose capsules, rice flour, and magnesium stearate to improve consistency and stability.
Enhanced Formulas: Some products may include synergistic ingredients like Vitamin B6 or Vitamin C to further boost immune support and overall efficacy.

Core Components: The Active Ingredients in Zinc Bisglycinate

At its heart, zinc bisglycinate is a chelated mineral, which means a metal ion (zinc) is bonded to an organic molecule, in this case, the amino acid glycine. The term 'bisglycinate' specifically refers to two (bis) glycine molecules attached to a single zinc ion. The production of this compound typically involves a chemical reaction between a zinc source, such as zinc oxide or zinc sulfate, and glycine. The resulting compound, Zn(H2NCH2COO)2, is a white, fine crystalline powder with superior properties for supplementation.

The chelation process is crucial because it significantly improves the bioavailability and tolerability of the supplement. The stable chemical structure protects the zinc ion from interacting with other substances in the digestive tract, like phytates found in grains and legumes, that would normally inhibit mineral absorption. This allows the zinc-glycine complex to be absorbed intact through the intestine, using the body's natural pathways for amino acid absorption.

The Role of Glycine

Glycine is the smallest of the 20 common amino acids and serves a vital function in creating the highly absorbable zinc bisglycinate molecule. By binding to the zinc, it effectively chaperones the mineral through the intestinal wall, protecting it from common dietary inhibitors. Glycine is also a key component of collagen, the most abundant protein in the body, and it plays a role in numerous biological processes, from supporting the nervous system to helping with antioxidant functions. Its small size and role in protein synthesis make it an ideal partner for mineral chelation, as the body can readily utilize both components of the complex.

Inactive Ingredients: Fillers, Binders, and More

While zinc bisglycinate is the star ingredient, commercial supplements contain other inactive ingredients. These additives are not for nutritional benefit but for practical reasons, such as improving the supplement's consistency, stability, and manufacturability. The exact inactive ingredients will vary by manufacturer, but common examples found in capsule formulas include:

Capsule Material: Many brands use vegetarian capsules made from hypromellose (a type of cellulose) or other plant-based materials.
Flow Agents: To prevent ingredients from clumping during production and storage, anti-caking agents like silicon dioxide (silica) are often used.
Lubricants: Magnesium stearate is a common lubricant that helps prevent the contents from sticking to manufacturing equipment. For vegetarian supplements, this is typically sourced from vegetables.
Bulking Agents: Fillers such as microcrystalline cellulose or rice flour are sometimes added to ensure consistent capsule size and to provide substance, especially for small-dose supplements.

It is important to check the product label for the full list of inactive ingredients, especially for those with allergies or specific dietary restrictions. Reputable manufacturers will typically ensure their products are free from common allergens and undesirable additives.

Comparison of Zinc Bisglycinate with Other Forms

Understanding why the specific ingredients in zinc bisglycinate are beneficial can be clarified by comparing it to other common zinc supplements. Different formulations affect absorption, digestive comfort, and potential interference with other nutrients.


Feature	Zinc Bisglycinate	Zinc Gluconate	Zinc Citrate
Bioavailability	High; significantly better than gluconate in studies.	Moderate; lower absorption than bisglycinate.	Moderate; absorbed similarly to gluconate and sulfate.
Gastrointestinal Tolerance	Excellent; gentler on the stomach, causing fewer side effects like nausea.	Fair; can cause stomach upset, especially on an empty stomach.	Fair; can cause gastric distress in some individuals.
Absorption Mechanism	Absorbed intact through amino acid transport pathways.	Absorbed via active transport mechanisms in the intestine.	Absorbed via standard mineral transport pathways.
Dietary Interactions	Chelation protects zinc from dietary inhibitors like phytates.	More susceptible to interference from dietary phytates and other minerals.	Also susceptible to interference from dietary components.
Stability	Highly stable chelate, resistant to degradation.	Generally stable, but can be less stable than a chelate.	Good stability, but not as protected as a fully reacted chelate.

Synergistic Ingredients and Additives

Some manufacturers add complementary ingredients to their zinc bisglycinate formulas to enhance specific benefits. For example, Vitamin B6 is often included to support nervous system and immune functions. Other products may combine zinc with antioxidants like Vitamin C and Selenium to boost immune support and benefit skin health. When evaluating a supplement, consider the purpose of these additional ingredients to ensure they align with your health goals. A comprehensive product label will detail all active and inactive components, and a quality product will be transparent about its sourcing and manufacturing. For further reading on mineral bioavailability, the National Institutes of Health offers extensive resources on the topic.

Conclusion

In essence, the ingredients in zinc bisglycinate revolve around two primary components: elemental zinc and the amino acid glycine, which are chemically bonded in a chelated form. This chelation process is the key to its superior bioavailability and gentle digestive profile, distinguishing it from less-effective zinc salts like gluconate or citrate. Surrounding this core compound are various inactive ingredients, which typically include capsule material, fillers, and flow agents that ensure product quality and shelf life. For those seeking efficient and well-tolerated zinc supplementation, understanding the specific role of each component can help make an informed decision and contribute positively to overall health and wellness.

Frequently Asked Questions

The primary function of glycine is to chelate, or bind to, the zinc ion. This creates a stable compound that protects the zinc from dietary inhibitors, allowing for more efficient and complete absorption through the small intestine.

Zinc bisglycinate is absorbed better because it utilizes the body's amino acid transport pathways to pass through the intestinal wall intact, whereas other forms can be disrupted by other minerals or dietary factors.

No. While zinc bisglycinate is the active component, commercial supplements also contain inactive ingredients. These include capsule materials, fillers, binders, and lubricants that assist with the manufacturing process and product consistency.

While generally considered safe, some individuals may have sensitivities to inactive ingredients. It is best to check the product label for a full list if you have known allergies or sensitivities.

Zinc bisglycinate itself is typically suitable for vegetarians and vegans. However, it is important to check the inactive ingredients, particularly the capsule material, as some may contain animal-derived gelatin.

Due to its chelated form, zinc bisglycinate is less likely to interfere with the absorption of other minerals compared to some inorganic zinc salts. Its absorption via amino acid transporters helps it bypass common mineral-mineral absorption competition.

The manufacturing process involves a chemical reaction where a zinc source, like zinc oxide, is combined with two molecules of glycine in a controlled environment to form the stable chelate compound.