Shea butter has been used for centuries (perhaps millennia) as a skin treatment in Africa, particularly for newborn infants. Although the clinical data often referred to by the cosmetic companies that market shea butter are hard to locate, recent scientific studies support its alleged therapeutic value in treatment of certain skin disorders.
The bioactive substances in shea butter reside in the unsaponifiable fraction – the oil-soluble constituents that would not react with alkali to form soap – which is a by-product of the CBE/CBI production process. They include anti-oxidants such as tocopherols (vitamin E) and catechins (also found in green tea).
Alander and Andersson (2002) and Alander (2004) identified other specific compounds such as triterpene alcohols, known to reduce inflammation; cinnamic acid esters, which have limited capacity to absorb ultraviolet (UV) radiation; and lupeol, which prevents the effects of skin aging by inhibiting enzymes that degrade skin proteins. Shea butter also protects skin by stimulating production of structural proteins by specialized skin cells.