Glossary
Chelate.
Direct answer
A chelate is a compound in which a metal ion is held at several points by an organic molecule, often an amino acid, forming a claw-like ring. This wrapping shields the mineral from precipitation and from binding to other constituents of the gut contents, which can alter how much is absorbed.
The word chelate on a label says very little on its own. What counts is the ligand used, the stability of the bond in the acidity of the stomach and the proportion of the mineral that is genuinely chelated. Comparing two products on that single word therefore leads to misleading conclusions.
In horses, most minerals come from forage, whose content varies with soil and region, and they meet very large volumes of plant material in the gut. In humans, intake is spread across a mixed diet of smaller volume. The bioavailability of a chelate consequently does not transfer from one species to the other.
The evidence letter
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