BHT stands for butylated hydroxytoluene, a synthetic antioxidant which is commonly used as a food additive. Synonyms for BHT include butylhydroxytoluene, 2,6-di-tert-butyl-4-methylphenol, and tert-butyl-4-hydroxytoluene. BHT is used to prevent oils and fats in foods from becoming rancid and unpleasant tasting. It is also used in cosmetics and pharmaceuticals as an antioxidant to prevent degradation of the products. BHT has been approved for use by the US Food and Drug Administration (FDA) and the European Union for use in food, but there is some controversy and debate about its safety and potential health effects.