Stearic Acid

What Is It?

Stearic Acid, Lauric Acid, Myristic Acid, Oleic Acid and Palmitic Acid are fatty acids that occur naturally in some foods. In cosmetics and personal-care products, fatty acids and mixtures of fatty acids such as Stearic Acid, Oleic Acid, Lauric Acid, Palmitic Acid and Myristic Acid are used in a variety of cosmetic creams, cakes, soaps and pastes.

Why Is It Used?

The following functions have been reported for these ingredients.

  • Opacifying agent – Myristic Acid, Palmitic Acid
  • Surfactant cleansing agent – Stearic Acid, Lauric Acid, Myristic Acid, Oleic Acid, Palmitic Acid
  • Surfactant emulsifying agent – Stearic Acid, Palmitic Acid

Scientific Facts

Stearic Acid, also known as Octadecanoic Acid, is obtained from animal and vegetable fats and oils. Humans have the ability to synthesize Stearic Acid. In general, fatty acids are used in the production of hormones that regulate a variety of functions, including blood pressure, blood clotting and immune response.

Safety Information

The Food and Drug Administration (FDA) includes Stearic Acid on its list of direct food additives considered Generally Recognized As Safe (GRAS). Stearic Acid is also permitted as a direct food additive in chewing gum base. The FDA also includes fatty acids on its list of food additives permitted for direct addition to food. The safety of Stearic Acid, Lauric Acid, Myristic Acid, Oleic Acid and Palmitic Acid has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel. The CIR Expert Panel evaluated the scientific data concluded that these ingredients were safe for use in cosmetic products.

CIR Review: The CIR Expert Panel noted that Oleic, Lauric, Palmitic, Myristic, and Stearic Acids are fatty acids with hydrocarbon chains ranging in length from 12 to 18 carbons with a terminal carboxyl group. These fatty acids are absorbed, digested, and transported in animals and humans. Few effects were was observed in acute toxicity testing when Oleic, Lauric, Palmitic, Myristic or Stearic Acid or cosmetic formulations containing these fatty acids were studied. There were no adverse effects observed at high doses in a chronic study.

Results from topical application of Oleic, Palmitic and Stearic Acid to the skin produced little or no apparent toxicity. Studies using product formulations containing Oleic and Stearic Acids indicate that neither were sensitizers nor photosensitizing agents. These fatty acids were not eye irritants. Lauric, Stearic and Oleic Acids were noncarcinogenic. In primary and cumulative irritation clinical studies, Oleic, Myristic and Stearic Acids at high concentrations were nonirritating. Cosmetic product formulations containing Oleic, Lauric, Palmitic and Stearic Acids at concentrations ranging up to 13% were not primary or cumulative irritants, nor sensitizers.

FDA: Link to Code of Federal Regulations for Stearic acid

Stearic Acid, Lauric Acid, Myristic Acid, Oleic Acid and Palmitic Acid may be used in cosmetics and personal care products marketed in Europe according to the general provisions of the Cosmetics Regulation of the European Union. If these ingredients are derived from animal sources, they must comply with European Union animal by-products regulations.

More Scientific Information

Stearic Acid is a waxlike fatty acid found mainly in animal tallow but can also be found in cocoa butter and other vegetable fats. Stearic Acid and other fatty acids are used as intermediates in the manufacture of fatty acid salts which are, in turn, used as emulsifiers, emollients and lubricants.

Resources

Find out more about the regulation of Food Additives by the Food and Drug Administration