Minerals, like magnesium and iron, are metal ions which like to attach to other compounds. The compounds to which they attach can affect how well they are absorbed and how available they are for use in the body. An amino acid chelated mineral is one in which a mineral has been chemically attached to an amino acid, and there is evidence that some, but not necessarily all, of these types of compounds may improve mineral absorption. For information about specific chelated amino acids, such as iron bis-glycine, magnesium diglycinate, zinc bis-glycinate, and selenomethionine (a chelate of selenium), see the full answer >>
You can also learn more about forms of calcium, magnesium, iron, zinc and other minerals in ConsumerLab.coms reviews of these supplements, and in the Review of Multivitamin and Multimineral Supplements.