Alpha hydroxy acids or AHAs are a group of mild organic fruit acids found in various fruits, vegetables and sugar cane.
Each AHA molecular structure varies with size. Glycolic acid is the first member of the alpha-hydroxy acid family of carboxylic acids. Glycolic acid, as the smallest AHA molecule, is highly suitable for skin care use, being present in normal skin, blood and other tissues of the human body. It also is a constituent of sugar cane juice.
Glycolic acid possesses great penetration ability and acts not only as a softening agent, but also as a delivery vehicle for other compounds. It may be combined with other keratolytic peeling agents, such as salicylic or lactic acids.
The results are remarkable in the appearance of the skin with a regular use of glycolic acid. The skin shows considerable improvement in skin conditions such as acne, in-grown hair, ichthyosis, photodamage, pigmentation and prematurely aged skin.
AHAs are water soluble, meaning that they can be applied in water solutions.
The pH is the factor that makes these solutions effective.The lower the pH, the more acidic the solution, and the more irritation caused on the skin. The normal use strength during a facial treatment is a pH of 3.0- 3.5 in a 10-50% glycolic solution. In a medical office, the pH of a peel is usually set at 1.7 in a 50-70% glycolic solution.
Glycolic acid peels are normally well tolerated by most people. AHAs help promote corneocyte shedding. transforming the basal cells into keratinocytes and speeding their migration into the stratum corneum.
The small molecular structure of glycolic acid is thought to work through a combination of reducing skin inflammation, promoting earlier removal of dry skin scales and optimizing moisturizing. These factors promote a healthy looking skin.
When AHA is applied to photodamaged skin, the skin appears to gain a more even texture, fine lines appear less obvious, pigmentation is reduced and the skin gets smoother and more hydrated. Skin analysis after a three-week study noted that fine lines became about 33% less noticeable. Some studies concluded that glycolic acid produced a 300% increase in the moisture content of skin after twice-daily application for three weeks.
Glycolic acid also may help lighten the skin when used in conjunction with skin-bleaching agents such as kojic acid.
AHAs have helped control acne breakouts. Additionally, rosacea treated with milder solutions of AHA (pH 3.5) appears to be calmed and hydrated. The skin appears to have less inflammation and becomes more normalized.
It is necessary to give the skin a break from using glycolic acid every three to four months. Stop for a month and then continue using it again. Overuse of anything may actually reverse what one is trying to achieve in the first place.
First time users of glycolic acid may notice some areas of slight redness, along with peeling on the forehead, cheeks or chin. This is a normal process as long as excessive irritation doesn't occur. With continued use, the skin begins to normalize in texture and appearance.
In the case of acne skin, the mild exfoliation action of AHA helps to soften the top of the lesions without any uncomfortable manipulation. Due to their acidic nature, glycolic acids also help reduce the proliferation of bacteria and reduce skin inflammation.