Should you add glycolic acid to your routine?

Many exfoliation products out there contain glycolic acid.  Why? Because glycolic acid is “popular”.

There is nothing special about glycolic acid. It’s a hydroxy acid like lactic acid (which I like better) but it has no specific problems. Another great hydroxy acid is ascorbic acid (vitamin C) but it’s unstable in contact with air, it will oxidize fairly quickly and go brown and “bad”.

Why is glycolic acid so popular? The legend goes that it is smaller than other hydroxy acids so it “penetrates” better. There is no evidence that this is the case.

Lactic acid molecular weight: 90

Glycolic acid molecular weight:  76

This slight difference would make no difference to your skin. For an acid peel, what matters is the acidity of the solution. The pH of a solution is determined by the pK and the concentration (molarity) of the acid, molecular weight has no effect.

I have no explanation for the myth, although maybe the formulators used percent for concentration when comparing the solutions (that would be a silly mistake) rather than molar concentration.

Formulators are humans, and skin care companies have to adapt to the current mood to survive: we sometimes are sensitive to the pressure of the internet, as long as the change is not hurting quality and performance..

A mild acidic exfoliator is still the best super-fast treatment to make you look ready for a high school reunion or a wedding. So, the answer is no, you don’t need to add glycolic acid to your routine, but a mild acidic exfoliator is worth adding.

As always, please follow the instructions on the label. Even a very mild acidic exfoliator, when left too long, may hurt your skin. Live cells (except those in our stomachs) don’t like acidity much.

Hannah

References

Moy LS, Howe K, Moy RL. Glycolic acid modulation of collagen production in human skin fibroblast cultures in vitro. Dermatol Surg. 1996 May;22(5):439-41. doi: 10.1111/j.1524-4725.1996.tb00344.x. PMID: 8634806.

Ceilley RI. Treatment of Actinic Purpura. J Clin Aesthet Dermatol. 2017 Jun;10(6):44-50. Epub 2017 Jun 1. PMID: 28979656; PMCID: PMC5605207.

DISCLAIMER: These claims have not been evaluated by the FDA and are not intended to diagnose, cure, treat or prevent any disease.