The ancient Egyptians knew that if they bathed in sour milk (lactic acid) their skin would become softer and smoother.
If you want strong firm taught muscles you exercise them, right? You apply a moderate stress in order to induce repair and strengthen mechanisms, and end up with stronger muscles.
If you want a smarter brain you study, right? You do courses, do crosswords, learn languages, stay mentally active and challenged. Only by exposing our ignorance can we achieve knowledge. Only children think they know everything.
And if you want stronger smoother skin you – - – do what?
As is exercise for your muscles, as is study for your brain, you challenge your skin by exfoliation.
Exfoliation can be achieved lots of ways, but the gentlest easiest and least expensive method is by using alphahydroxy acids (AHAs) in your skin care.
The archtypic alphahydroxy acid is glycolic acid. Glycolic acid is found in some sugar canes, and is a little 2-carbon compound with a carboxylic acid group on one C and a hydroxyl and a couple of hydrogens on the other C. Simple.
Glycolic acid loosens up surface dead skin cells. These then wash off, leaving a brighter smoother surface. But that is not all….
It also kills a few surface cells, but not many. Just enough to induce a whole lot of repair mechanisms, such as vascular endothelial growth factor, interleukin 1alpha, and fibroblastic generation of collagen and glycosaminoglycans.
The new collagen means the skin is stronger and smoother, with fewer lines. The new glycosaminoglycans mean the skin moisture content improves.
Glycolic acid also has a role in diminishing pigmentation. By removing surface dead cells it helps wash through the pigment that is already there, but it also has a minor effect in reducing the production of melanin by suppressing tyrosinase. In this regard it is not as strong as some other products, but it helps.
There are other alphahydroxyacids such as lactic acid and tartaric acid (from grapes) that have similar effects. Lactic acid is like a glycolic acid molecule but with an H removed from the non-acidic C and a CH3 put there instead. Tartaric acid is like two glycolic acid molecules stuck non-acidic end to non-acidic end, so it is a four-carbon chain comprising a COOH at each end and an OH and an H on each of the 2nd and 3rd carbons. Malic acid, from apples, is the same as tartaric acid except that there’s another H in place of one of the OH groups. Finally citric acid, from citric fruits, has a 5-carbon chain with a 6th carbon attaching to the 3rd of these. These three end-carbons are each acidic, being COOH groups. The 3rd carbon has an OH which, being next to the COOH of the 6th carbon, defines this as an alphahydroxy acid like the rest. The 2nd and 4th carbons have just Hs on them.
How they are used
Essentially AHAs are used either as a peeling agent in the clinic or in a cream for home use. As a clinic peel, glycolic acid, for example, is applied at somewhere between 20% and 70%. Mild to moderate peeling is produced over the next few days, and the skin brightens quickly. As part of home care, the exfoliative action of the AHAs makes it reasonable to combine them with cleansers, but they can also be applied and left on in low dosage and at a gentle pH.
What to look out for
Glycolic acid, lacic acid, tartaric acid. Molecule for molecule they are similar in action, but, because of its smaller size, you get more acidic effect from a mg of glycolic acid than a mg of say lactic acid. Lower pH levels in the product equate to greater acidity, faster effect, more peeling, and greater irritation. Remember the pH scale is a logarithmic scale, so a ph of 3 is 10 times more acidic than a pH of 4, and 100 times more acidic than a pH of 5. On the other hand, the hydrating effect of glycolic acid or any AHA is independent of pH.
What to buy
Talk to your beauty therapist. You want something strong, but tolerable. The pursuit of beauty is not an exercise in masochism.
What to do.
Use a cleanser with an AHA. Try an AHA cream at night. Try a peel, but remember: they sting.