What is alpha hydroxy acid

Alpha hydroxy acids (AHA) also called fruit acids, are synthetic versions of organic carboxylic acids derived from sugar-containing fruits. Alpha hydroxy acids compounds include glycolic acid (from sugar cane), citric acid (from citrus fruit), lactic acid (from milk and pickled vegetables), malic acid (from apples) and tartaric acid (from grapes). Alpha hydroxy acids treat acne by helping to remove dead skin cells and reduce inflammation. Alpha hydroxy acids also stimulate the growth of new, smoother skin. This helps improve the appearance of acne scars and gives the impression of smaller pores. Products containing alpha hydroxy acids are marketed for a variety of purposes, such as smoothing fine lines and surface wrinkles, improving skin texture and tone, unblocking and cleansing pores, and improving skin condition in general. Sometimes alpha hydroxy acids are used in cosmetics for other purposes, such as to adjust the pH (the degree of acidity or alkalinity).

Alpha hydroxy acid-containing products cause exfoliation or shedding of the surface old, dead skin. The extent of exfoliation depends on the type and concentration of the alpha hydroxy acid, its pH, and other ingredients in the product.

Some products containing alpha hydroxy acids have been marketed for uses such as treating acne, removing scars, and lightening discolorations. Among these are some products marketed as “skin peelers,” which may contain relatively high concentrations of alpha hydroxy acids or other acids and are designed to remove the outer layer of the skin.

Based on industry-sponsored studies, the Cosmetic Ingredient Review Expert Panel — the industry’s self-regulatory body for reviewing the safety of cosmetic ingredients — concluded that products containing the alpha hydroxy acids glycolic and lactic acid are safe for use by consumers if:

• The alpha hydroxy acid concentration is 10 percent or less.
• The final product has a pH of 3.5 or greater.
• The final product is formulated in such a way that it protects the skin from increased sun sensitivity or its package directions tell consumers to use daily protection from the sun.

How do alpha hydroxy acid treatments work?

With time and sun exposure there is a gradual but slow-down in the rate at which old cells leave the surface of the skin and are replaced by newer cells. This results in a surface layer of dead skin cells that are responsible for the appearance of aged skin. Alpha hydroxy acids encourage the shedding of old, sun-damaged surface skin cells.

They loosen the glue-like substances that hold the surface skin cells to each other, therefore allowing the dead skin to peel off gently. The skin underneath has a fresher, healthier look with a more even color and texture.

With high concentration and long-term use, alpha hydroxy acids may also affect the deeper layers of the skin. Collagen and elastin regenerate making fine lines less obvious.

Alpha hydroxy acid benefits

Alpha-hydroxy acid (AHA) agents, such as glycolic acid and lactic acid, have been used as therapeutic agents in cosmetics to rejuvenate the skin as anti-aging agent for more than a quarter of a century ¹. Alpha hydroxy acid is used in the treatment of several skin conditions such as acne, scar, pigmentation, skin dryness and wrinkles ². Alpha hydroxy acid preparations are recommended for those whose skin is showing signs of ageing. Fine lines, brown marks and dry spots (actinic keratoses) can improve with regular applications or peels. Glycolic acid may also prove helpful for those prone to acne. It is safe in pregnancy. New more lipophilic alpha hydroxy acids will be utilized more in the future, especially when targeting oily skins ³.

The well-known benefits of alpha hydroxy acid’s include exfoliation, moisturization, reduction of fine lines and wrinkles, collagen synthesis, firming and skin lightening. Glycolic acid is the smallest at alpha hydroxy acid compounds, extracted from sugar. Formulations containing 10-15% glycolic acid are currently used topically, vaginally and rectally or as ophthalmic preparations for treatment at skin aging and hyper pigmentation due to sunlight ².

Alpha-hydroxy acids involve in metabolic pathways and essential cell cycles, including Krebs cycle, glycolysis and biosynthesis of serin ². Alpha hydroxy acids act on both the epidermal and the dermal levels. When applied to the skin, alpha hydroxy acids stimulate the exfoliation of epidermal cells in the stratum corneum by interfering with the ionic bonding between these cells. This results in the sloughing off dull and rough skin and promotes cellular renewal. Initially used for treatment of hyperkeratosis and other skin conditions affecting subcutaneous turnover, alpha hydroxy acids were found to promote softer, smoother skin, faded wrinkles, lightened age spots, and decreased blemishes. Alpha hydroxy acids also improve the subcutaneous barrier function, increase epidermal proliferation and thickness, and restore hydration and pursiness through an increase in hyaluronic acid.

Alpha hydroxy acid for acne

There are two types of alpha hydroxy acids that are used in nonprescription acne products are glycolic acid and lactic acid. Glycolic acid 10 (Glycolic Acid – 10%) percent powerfully exfoliates and helps bring new skin cells to the surface, which helps the complexion appear smoother.

Glycolic acid can take acne regimen to the next level, helping you to achieve even more reliably clear skin. After you’ve been on acne regimen for at least 1 month, try using glycolic acid in place of your usual nightly moisturizer every 2-3 days. Alternately, mix an equal amount of glycolic acid and moisturizer in your palm and apply this way every night.

Usage: Use a thin line when applying to the face. More than this and it may sting too much.

Flakiness control: If you are on acne regimen and are having problems with flaky skin, adding in glycolic acid as outlined above will completely eliminate flakes.

Alpha hydroxy acid peels

Alpha hydroxy acid peels are an ideal treatment for busy people who are unable to take time off work for a deeper peel or laser resurfacing. Alpha hydroxy acid peels gently retexture the skin over a few months. The treatments are also helpful in stabilizing oily or acne-prone skin and improving skin tone.

A glycolic acid peel takes about 15–20 minutes. It is usually repeated at one to two weekly intervals as it is superficial, so recovery is rapid. The strength of each peel ranges from 20 to 70%, depending on skin sensitivity and starting gently.

The face is cleansed thoroughly, and then the peel solution is applied for three minutes. It stings mildly. The solution is then washed off.

Treated skin may be a little pink immediately after treatment. A little peeling may occur over the next few days. It can be disguised with moisturiser or normal make-up.

Alpha hydroxy acid skin care products

There are many products with varying concentrations of various alpha hydroxy acids in differing bases. For the best results, leave-on preparations should be applied at night, if necessary twice daily. They can be alternated with other anti-ageing preparations including retinoid creams and vitamin C.

There are specific preparations for dry, normal and oily skin. Those available from medical practitioners are stronger than those at pharmacies and beauty therapists.

Don’t forget the essential skincare tip — always protect your skin from the sun!

Alpha hydroxy acid side effects

A negative side effect of alpha hydroxy acids may be a sensation of stinging or burning immediately after application, particularly on people with sensitive skin. The US U.S. Food and Drug Administration (FDA) received a total of 114 adverse dermatologic experience reports for alpha hydroxy acid-containing skin care products between 1992 and February 2004, with the maximum number in 1994 ⁴. The reported adverse experiences included burning (45), dermatitis or rash (35), swelling (29), pigmentary changes (15), blisters or welts (14), skin peeling (13), itching (12), irritation or tenderness (8), chemical burns (6), and increased sunburn (3). The frequency of such reports for skin exfoliating products that contain alpha hydroxy acids has been considerably lower in subsequent years. The more serious adverse reactions appear to occur most often with products that cause the greatest degree of exfoliation, such as “skin peelers.”

1. Effects of alpha-hydroxy acids on the human skin of Japanese subjects: the rationale for chemical peeling. J Dermatol. 2006 Jan;33(1):16-22. https://www.ncbi.nlm.nih.gov/pubmed/16469079[↩]
2. Moghimipour E. Hydroxy Acids, the Most Widely Used Anti-aging Agents. Jundishapur J Nat Pharm Prod. 2012;7(1):9-10. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3941867/[↩][↩][↩]
3. Green B. After 30 years … the future of hydroxyacids. J Cosmet Dermatol. 2005;4(1):44–5. doi: 10.1111/j.1473-2165.2005.00159.x[↩]
4. Alpha Hydroxy Acids. https://www.fda.gov/cosmetics/productsingredients/ingredients/ucm107940.htm[↩]