Ferrous bisglycinate is an iron amino acid chelate. It is formed by reaction of ferrous iron with two molecules of the amino acid glycine by a covalent bound in a process called chelation. Ferrous bis-glycinate is more effectively absorbed and passes through the stomach and small intestine without breaking apart. Ferrous bisglycinate is claimed to have better patient compliance because of fewer gastrointestinal tract side effect associated with many forms of iron salts include nausea, indigestion, constipation and diarrhea. Ferrous bisglycinate is effective for the prevention and treatment of iron deficiency or iron deficiency anemia.