3,5-Di-tert-butyl-4-hydroxyphenylacetic acid (BHT) is an antiaging agent that has been used in food packaging and cosmetics. BHT is a functionalized triethoxysilane with phenyl groups attached to the silicon atoms. BHT is an antioxidant that protects against lipid peroxidation and prevents the formation of free radicals by reacting with peroxy radicals. It has been shown to have a protective effect on skin cells when applied topically. BHT also has protective effects against environmental stressors such as UV radiation, ozone, and cigarette smoke.