Known as AHA’s, fruit acids found in citrus fruits (citric), apples (malic) and papaya (pyruvic). Other acids in the family include lactic acid (from milk), tartaric acid (from red wine), and the most exciting and therefore most widely researched, glycolic acid (from sugar cane).
Lactic acid has been used to soften the skin for centuries and resurfaced in modern cosmetic creams in the 70’s after studies showed that combined with sodium lactate, it improved the skin’s moisture-holding capacity. Tartaric acid, too, has been in used for years: French women used to apply red wine to their faces. Collectively, AHA’s have recently been in the vanguard of the new cosmeceutical movement as they are used to formulate creams which perform beyond the normally superficial cosmetic role.
The dead skin cells build-up which gave icthyosis sufferers their crocodile-skin appearance could be alleviated with a glycolic acid preparation. They showed that the acid molecule dissolved the protein bond which kept a dead skin cell attached. Not only did glycollic acid prove capable of normalizing the desquamation process but could also improve the skin’s own moisture-retaining capabilities.
Dermatologists use AHA’s in concentrations up to 70 percent to perform acid peels and prescribe 5-20 percent AHA creams. The percentage contained in cosmetic creams varies from 1-7 percent. Some over the counter pharmacy brands contain between 5-15 percent.
Cosmetic AHA preparations can help keep the skin free of dulling and skin-pore clogging dead cells. They can make the skin slightly brighter and improve its moisture retention. Unlike the physician-prescribed higher concentrations, they cannot produce radical improvement in the ageing complexion. Recent studies suggest that AHA’s may also act as free radical scavengers, sending messages to the dermis to increase collagen production and increase the skin’s tolerance to retinoids.