Magnesium stearate

Magnesium stearate, a salt of stearic acid, is widely used in cosmetics, foods, and capsules as a lubricating agent. In dietary supplements it may contain a mixture of magnesium salts of different fatty acids.

Magnesium stearate is approved by the U.S. Food and Drug Administration (FDA) as generally recognized as safe (GRAS) (21CFR184.1440) and is generally regarded as being nontoxic following oral administration. Oral consumption of large quantities may produce a laxative effect or cause mucosal irritation 1.

This ingredient can be found in the following products in United States:


  1. Handbook of Pharmaceutical Excipients. Gurnee, IL: Pharmaceutical Press, 2006.