Medically reviewed by
Sara Osman,RD,PT
Introduction
Zinc is an important trace mineral involved in cellular metabolism. [1]
It is present in all body tissues and fluids and is necessary for almost 100 enzymes to carry out vital chemical reactions. [3,4]
Zinc facilitates several enzymatic processes related to the metabolism of protein, carbohydrates, and fats. [2]
- Zinc is absorbed by the small intestine during digestion. [2]
- Zinc when consumed in liquid form on an empty stomach has a high absorption rate of around 60-70% whereas absorption from solid diets is less efficient and varies depending on zinc content and diet composition. [3]
- Small amounts of zinc are more efficiently absorbed by the body than large amounts. [2]
- Also, the bioavailability of zinc from plant sources is lower than that from animal foods, as phytates present in plant sources inhibits its absorption. [1]
- More than 85% of zinc is stored in skeletal muscle and bone. [2]
- The total body zinc content is estimated to be 2-3 g. [3]
- The body has no specialised long term zinc storage system and hence daily intake of zinc is needed to maintain steady levels. [1]
- Zinc is primarily excreted through faeces and losses may range from less than 1 mg/day with a zinc-poor diet to greater than 5 mg/day with a zinc-rich diet. [2]
- Less than 10% of the excretion happens through urine. [2] Starvation and muscle catabolism increase zinc losses in urine. [3]
- Also, rigorous exercise and high temperatures can lead to high losses through perspiration. [3]
Body Functions
Recommended Daily Intake
[adinserter block="1"]
Deficiency Symptoms
Zinc Food Sources
[adinserter block="11"]
Excessive Intake/ Toxicity Side Effects
Groups At Risk of Zinc Deficiency
Zinc Interaction With Other Nutrients
- Iron –High supplementary iron intakes might decrease zinc absorption if both are taken without food. It is therefore advised to take iron and zinc supplements with food. [1,2] However, iron-fortified foods are not known to significantly affect zinc absorption. [1]
- Copper –Increased zinc intake can reduce copper absorption. Doses of 60 mg/day (50 mg from supplements and 10 mg from food) for 10 weeks or more have shown this effect [2]
- Phosphorus – Certain dietary sources of phosphorus, including phytate and phosphorus-rich proteins, such as milk casein may reduce zinc absorption. [2]
- Calcium – High dietary calcium phosphate supplementation (1360 mg calcium/day) may decrease zinc absorption but there is no definitive evidence yet. [2,3]
- Phytic acid – Foods that are rich in phytic acid, found in plant-based foods including grains and legumes, can bind to zinc and inhibit its absorption. [2]
- Folate – Low zinc intake may decrease folate absorption. However, other studies have found that low zinc intake did not affect folate nutriture and that folate supplementation does not adversely affect zinc status so researchers are still working on this point. [2]
Nutrient Profiles For Food Groups
Medically reviewed by
Sara Osman,RD,PT
About Veganism
Learn more about the origins , different types and potential nutritional deficienciesOur Mission
Learn more about our mission, our approach and the story behind the project2050 Challenges
Learn more about the Environmental, Health and Societal challenges of the futureSubscribe to Newsletter
