Dietary factors influencing zinc absorption.
Level 5 - mechanism / opinion, no new human data
Narrative review without systematic search or meta-analytic pooling
PubMed 10801947 · doi:10.1093/jn/130.5.1378S
What was done
Review of dietary components influencing human zinc absorption and bioavailability, focusing on inhibitors such as phytates, iron, and cadmium, as well as enhancers including dietary proteins, amino acids, and organic acids.
What was found
The abstract reports no numerical values or effect sizes. Phytates (specifically inositol hexaphosphates and pentaphosphates) strongly inhibit zinc absorption from composite meals, whereas lower inositol phosphates show little to no inhibitory effect. Phytate reduction via phytase treatment, precipitation, germination, fermentation, or genetic modification improves zinc bioavailability. Supplemental iron co-administered in supplements inhibits zinc absorption, though iron fortification within meals does not. Environmental cadmium also inhibits absorption. Overall protein content, specific amino acids (histidine, methionine), EDTA, and organic acids (such as citrate) enhance zinc absorption, while specific proteins like casein exert modest inhibitory effects relative to other protein sources.
Why it matters
Marginal zinc deficiency is common globally and is often driven by low bioavailability rather than inadequate absolute intake. Identifying key dietary inhibitors and promoters informs food processing, biofortification, and effective supplementation strategies.
Limits
The abstract provides a narrative synthesis without reporting quantitative metrics, statistical significance, or systematic study selection criteria. Individual study designs, sample sizes, and specific human populations are not detailed.
Cited by
- context Excess copper intake, such as from copper plumbing pipes, depletes zinc in the body.