fruit acids (AHA's)

back to ingredient overview

Alpha hydroxy acids (AHA) are a staple of numerous skin care product lines. They are occasionally touted as a new treatment, but in fact their cosmetic use has started several decades ago. AHA are a group of structurally related organic acids found in natural sources or synthesized in the laboratory.

These acids have strong exfoliating properties, stimulate new cell growth and absorb excessive oil on the skin. They make skin smoother and softer, and help to recover a dry skin. In the deeper layers of the skin they help stimulate the production of collagen. There are 5 different types of alpha hdroxy acids:

• glycolic acid
• citric acid
• malic acid
• lactic acd
• tartaric acid

Click on the different acids to read more about their specifics and what they can do for the skin.

High strength alpha hydroxy acids are used by dermatologists in chemical peels. Several studies convincingly demonstrated that such peels can reverse some signs of skin aging. In a study at the University of Los Angeles, California, forty five volunteers were treated with 50 percent glycolic acid or vehicle alone. The treatment was applied to one side of the face, forearms and hands for 5 minutes once weekly for 4 weeks. The researchers concluded that "application of 50 percent glycolic acid peels improves mild photo aging [aging due to sun damage] of the skin." Another study conducted at Hahnemann University School of Medicine, Philadelphia, Pennsylvania, tested a lotion containing 25 percent of glycolic, lactic or citric acid against a placebo lotion. The treatment was continued for 6 month. Alpha hydroxy acids treatment lead to a 25 percent increase in skin thickness, improved quality of elastic fibers and increased density of collagen. The researches concluded that alpha hydroxy acids "produced a significant reversal of epidermal and dermal markers of photo aging."