Alpha Hydroxy Acids – AHAs

Alpha Hydroxy Acids

This group of organic chemicals includes glycolic, lactic, citric, pyruvic, malic and tartaric acids. Often called fruit acids because of their origins (glycolic comes from sugar cane, lactic from fermented milk, citric from citrus fruits, pyruvic from papaya, malic from apples and tartaric from fermented grapes) they are now more usually synthesized for cosmetic use.

We like to think of alpha hydroxy acids as representing exciting new skin smoothing solutions but they are actually the oldest cosmeceuticals — by many centuries. When Cleopatra bathed in ass’s milk she was treating her skin with the surface refining and hydrating qualities of lactic acid. And when women rubbed the residue from the bottom of the wine barrel into the faces they were benefiting from the smoothing effects of tartaric acid,

AHAs refine the skin’s outer layer by dissolving the protein bond that keep the flattened, anucleic keratinocytes attached to the stratum corneum. Rid of its scaly build up, the skin feels smoother and looks brighter too.

Because they are not classified as drugs, AHAs are today incorporated into all manner of skin products — from washes and exfoliators to day creams and masks. Cosmetics creams tend to incorporate 1-8 per cent AHAs, specialist salon ranges up to 15 per cent and physician dispensed ranges anywhere up to about 20 per cent. Concentrations of 30-90 per cent are also used to perform peels.

Why you might use them

The applications for AHAs are wide and varied. If your skin is prone to spots, an AHA preparation can help clear the pore-plugging cells that cause them. If your skin is rough and dry, AHAs can smooth it and make it better able to hold moisture. If your complexion has dulled with age, AHAs can brighten it They may also help to lighten dark spots and melasma maybe by increasing cell turnover beyond the pigment-injecting capacity of the melanocytes.

Which AHAs to use?

There are many cosmetic AHA preparations now available over the counter, for example Estee Lauder’s Fruition, La Prairie Age Management and L’Oreal’s Excell range, each boasting its own superior cocktail of different acids, usually at 8% or much less. The companies tend to forgo more spectacular results in favour of producing products which are completely safe and pleasant to use meaning you can probably buy and use them with impunity.

Because it is the most widely studied and believed to be the most effective, most of the dermatologist- or specialist salon-dispensed preparations (MD Formulations, MD Forte, Murad, Neostrata to name a few) are based on 10-20 per cent glycolic acid. Glycolic acid’s efficacy is probably due to its size — it is the smallest AHA molecule (with only two carbon atoms to pyruvic’s eight) and so can penetrate further into the skin. It gives more rapid and marked results but can sting more on application — one of the reasons cosrnetic companies are reluctant to use it,

AHA body products can be extremely useful for the care and control of dry body skin. A well-formulated product will make rough knees and elbows silky smooth almost instantly.

How to apply AHAs

If you’re using a cosmetic AHA you could probably apply it morning and night with no adverse effects. A physician-only type AHA will probably be recommended for use at night only, again on a clean face.

If, however, you are using both Retin-A and an AHA formulation you may use the Retin-A at night and AHAs in the morning. This allows time for their different actions to take place (see below). Using an AHA in the morning also helps to put a useful barrier between your naturally acidic skin and often alkaline make-up products spot check which can upset the skin’s normal function. If you are ad- vised to use both it is best to use them on alternate nights — one to refine and to increase the penetration of the other. Risks and side effects Most AHAs will sting or at least tingle slightly on application but the feeling should subside within 30 seconds. The degree of reaction will depend on the acid concentration and your particular skin type. Some people notice very little or nothing at all.

Because the acid clears and thins the stratum corneum which makes up part of your skin’s natural sun shield, it is wise to use a daily sunscreen of at least SPF15 when using AHAs.

If you have sensitive skin you may find AHAs very irritating; the stinging may be persistent, or even intolerable and your skin can become red and inflamed. If this is the case you should stop using them, It’s possible that your stratum corneum is too broken down to cope with them. However, by initiating a sensitive skincare regime your skin might tolerate them better in the future.

Because you can buy so many different sorts of AHA products there are worries among some skin specialists that their overuse could denude your stratum corneum of too many cells leaving it prone to irritation.

Results

One of the gratifying things about AHAs is that their effects are almost instantaneous. Your skin should feel smoother within days. Your complexion should look brighter and within weeks you will probably notice that your previously dry skin needs less moisturizer to remain feeling comfortable and looking plump and moist, or that your oily skin develops fewer spots.