Cosmetics ingredients are essentially unregulated by the government, so it falls to retailers and consumers to decipher ingredient lists on personal care products. The glossary below defines some of the most common ingredients found in natural personal care products. However, as the Environmental Working Group points out, many of these ingredients can be sourced in different ways—for example, from animals, plants or chemical synthesis. In addition, unlike in the European Union, U.S. manufacturers are not required to list contaminants. Even an ingredient as seemingly safe as lavender extract may be extracted by gentle methods using water or alcohol or through the use of petrochemical solvents. Manufacturers should be more than willing to answer questions about the sourcing and extraction methods of their ingredients.
Alkyl benzoate: An emollient created by reacting alcohols with benzoic acid—derived from a vegetable resin—alkyl benzoate is used in shampoos, body wash, moisturizers and lotions for its conditioning and softening properties. It is given the lowest possible hazard score by the EWG.
Allantoin: An organic salt created by the oxidation of uric acid—a chemical produced when the body breaks down certain food substances—allantoin is found most often in moisturizers and anti-aging creams. It can help heal wounds, stimulate the growth of healthy tissue, relieve skin irritation and soften the skin, according to Stephen Strassler, president of Reviva Labs, based in Haddonfield, N.J. Allantoin can be extracted from the uric acid of cows, but in natural products is more likely to be extracted from plants such as comfrey and bearberry.
Biotin: Also called vitamin H or vitamin B7, biotin is a water-soluble B-complex vitamin produced naturally in the intestine. It is often found in hair care products to add body and texture. While it occurs naturally in animals, the vast majority of biotin used in cosmetics is plant-derived.
Glycerin: Also called glycerol or glycerine, glycerin is present in all natural lipids. It can be synthesized or derived from natural plant and animal substances by fermenting sugars or by mixing hot water with a fat to break it down into glycerol and fatty acids. Plant-derived glycerin is generally noted as vegetable glycerin on an ingredient deck. Glycerin is a humectant—able to absorb water from other sources—and when used in formulations with moisturizing agents, improves the skin’s water-holding capacity. Glycerin esters are used as emollients—or moisturizers—to soothe or soften the skin, and thickening agents. Common forms include glyceryl cocoate, glyceryl dipalmitate and glycerol monostearate.
Glycolic acid: Molecularly the smallest of the alpha hydroxy acids, glycolic acid is a hygroscopic (able to attract water molecules) crystalline solid that is water soluble. It is used in skin care products as an exfoliant to reduce wrinkles and acne scarring and improve the skin’s appearance. It works by weakening the lipids that bind the upper layer of the epidermis, dissolving the dead skin cells on the surface.
Isopropyl palmitate: This substance is an ester, created by reacting an acid with an alcohol. In this case, the base ingredients are isopropyl alcohol and palmitic acid, derived from palm oil. Isopropyl palmitate is used as an emollient, moisturizer and thickening agent in personal care products.
Lactic acid: A type of alpha hydroxy acid, or AHA, lactic acid is manufactured through bacterial fermentation of milk, corn or sugars from cane or grape. It is naturally produced by the body, creating muscle burn after strenuous activity. In skin care products it acts as a gentle exfoliant.
Lecithin: A mixture of phospholipids in oil, lecithin is created by degumming the extracted oil of seeds. The primary source of lecithin is soybean oil. Lecithin acts as a natural emulsifier and emollient, and can penetrate the epidermis to deliver substances to the cell level. Lecithin also contains choline and inositol, important components of cell membranes.
Lauryl glucoside: As a surfactant—short for surface active agent—and detergent, lauryl glucoside is used as a sudsing agent in personal care products. It is made from a coconut derivative combined with glucose, as is its close cousin, decyl glucoside. Both ingredients are mild and biodegradable, and can be used in place of harsher detergents such as sodium lauryl sulfate and sodium laureth sulfate, though they provide less sudsing action than the latter.
Salicylic acid: Also called beta hydroxy acid, or BHA, salicylic acid is an exfoliant and antimicrobial used for treating breakouts and blemishes. As a derivative of aspirin, or acetylsalicylic acid, it is a powerful anti-irritant. Unlike AHAs, BHA can penetrate and exfoliate inside the pore. Salicylic acid is also known to improve skin thickness and collagen production.
Mitchell Clute is a Fort Collins, Colo.-based freelance writer.