Zinc in the body, from absorption to deficiency and excess
What it found
Zinc is needed for hundreds of body processes, and regular intake is essential because the body cannot store it.
Too little zinc causes deficiency, and too much can cause harm, especially by lowering copper.
What they found
Studies in people and animals
Zinc deficiency
An estimated 17% of the world's population is at risk of not getting enough zinc. Inherited deficiency, called acrodermatitis enteropathica, is mostly caused by mutations in the SLC39A4 gene and shows up from birth.
Zinc toxicity
Taking too many zinc supplements is the most common cause of zinc excess. Doses above 50 mg/day may cause nausea, diarrhoea and stomach discomfort, and long-term excess can lead to low copper, anaemia and nerve problems.
Other findings
Zinc in the body
Zinc is the second most abundant trace element in the body after iron. More than 300 enzymes and 1000 transcription factors depend on it, and one in ten body proteins is a zinc protein.
Absorption and transport
Zinc is taken up mainly in the small intestine. ZIP4 and ZnT5B move zinc into gut cells, and ZnT1 moves it into the blood. In the blood, most zinc is bound to albumin.
What affects absorption
Amino acids from protein and citrate may help zinc be taken in, while phytates in legumes, beans and nuts, and casein and calcium in cow's milk, can reduce it. Fermentation and germination of foods also help by lowering phytate.
Zinc and other nutrients
Too much zinc can block the absorption of copper and iron, leading to copper deficiency and anaemia. Zinc supplements can also reduce the absorption of some drugs, including ciprofloxacin, doxycycline and risedronate.
What the authors conclude
“This shows that zinc can have potentially serious side effects, and it is not a harmless agent that can be prescribed without a strong justification”
Also in their conclusions
- They say zinc is an essential micronutrient that cannot be stored in significant amounts, so regular dietary intake is vital.
- They advise that zinc is not a harmless agent and should not be prescribed without strong justification.
- They call for more research on zinc carriers, on how zinc transporters are controlled, and on whether genetics plays a role in zinc toxicity.
How it was done
The authors wanted to give a concise overview of how zinc works in the body and to describe health problems linked to too little or too much zinc.
They reviewed existing research on how zinc is taken in, moved around and used by the body, and on inherited and acquired zinc deficiency and zinc toxicity.
What it can’t tell you
- This is a review of other studies, so it cannot prove cause and effect for any single finding.
- Many of the details come from lab and animal work, which cannot show what happens in people.
- The authors note that there is no clear agreement on the recommended daily zinc intake or on how much zinc is bound to albumin in the blood.
Who paid
- Conflicts
- Authors declare that they have no competing or financial interests to disclose.
- Authors work at
- GKT School of Medical Education, UK; Centre for Education, UK
The paper
- Title
- Role of zinc in health and disease
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Stiles LI, Ferrao K, Mehta KJ (2024). Role of zinc in health and disease. Clinical and experimental medicine. doi:10.1007/s10238-024-01302-6Free full textPubMed 38367035DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error