Health Risks of Magnesium Stearate

Magnesium stearate is a salt used by vitamin manufacturers as a filler in producing the majority of supplements sold in stores. Considered an additive, magnesium stearate is composed of magnesium and stearic acid and is used as a lubricant for machinery in producing vitamins.

Decreased Absorption

One of the main health risks of magnesium stearate, according to Ron Schmid, N.D., in his article “Dietary Supplements: What the Industry Does Not Want You to Know,” is the reduced level of absorption of vitamins in the required daily amount. Schmid reports a 65-percent decline in absorption of nutrients when magnesium stearate is present.

Allergic Reactions

The Organic Consumers Association maintains that fillers, such as magnesium stearate, may induce an allergic reaction in some people who are sensitive to food additives. Milk derivatives, such as lactose, are presumed to be found in fillers, such as stearic acid, and may produce similar side effects in those individuals prone to have similar reactions to milk or other dairy products.

Hazardous Warning

Science issued a Material Safety Data Sheet on magnesium stearate in October 2005, stating that the substance presented a hazardous health issue when ingested orally, causing damage to the liver. Under California Proposition 65, magnesium stearate was found to “cause cancer, birth defects or other reproductive harm.”

About this Author

Pamela Wake received a Master of Science degree from Pacific College in San Diego. She began writing in 1996 working in marketing communications and currently contributes health and nutrition articles to, The Healthy Times newspaper and is the Alternative Health Examiner for in San Diego.