What about exfoliating too often? In terms of overdoing it, yes, you can, and then your skin will respond with irritation and inflammation and that isn’t good for skin. But does exfoliating skin hinder or harm cell production? Some of my readers have asked me about something known as the Hayflick Limit. The Hayflick Limit is a phenomenon that explains how many times skin cells will be reproduced. There seems to be a preset genetic determination of the number of times a skin cell will be regenerated. This turnover limit only applies what happens in the lower layer of skin where skin cells are produced (the basal layer). What happens on the surface in regard to exfoliation doesn’t affect the number of times new skin cells are created. Exfoliation is strictly about the dead surface layer of skin and that doesn’t get anywhere near the lower layers where new skin cells are being reproduced. Besides, removing the top layers of skin doesn’t cause new skin cells to be formed; the two functions are not related. So you don’t need to worry about damaging new skin cells by using topical exfoliants. You do want to be careful to avoid exfoliants that are too strong or too abrasive because of the irritation and inflammation such products cause. They can harm skin more than help it, but that still doesn’t affect cell regeneration or speed up the Hayflick Limit.
You may have heard or read that some cosmetics companies are proclaiming that people should stop exfoliating their skin. The reasoning is that by doing so you hold on to your epidermal (surface) cells longer, which creates a more youthful look. There is no reason to preserve our epidermal cells (the outer layers of skin); after all, they die and shed normally! Routine exfoliation just helps them do it in a healthier, more normal manner. What they are confused about is the notion of wanting to preserve the basal layer of skin where skin cells are regenerated, yet that is not in any way related to exfoliation on the surface of skin. If there is research showing that exfoliation changes cell regeneration I have never seen it. What I have seen is lots of research showing that exfoliation is incredibly beneficial for skin. There is even research showing that glycolic acid can reduce skin cancer occurrences, which is astounding.
For the health and appearance of your skin, exfoliation is a key component. It is necessary for most skin types and is as basic as a gentle cleanser, sunscreen, and the need for skin to get topically applied antioxidants and cell-communicating ingredients!
(Sources: InternationalJournal of Cosmetic Science, June 2008, pages 175-182; Phytotherapy Research, November 2006, pages 921-934; Journal of Cosmetic Dermatology, September 2006, pages 246-253; Aesthetic and Plastic Surgery, May-June 2006, pages 356-362; Journal of Dermatology, January 2006, pages 16-22; Cosmetic Science, September-October 2002, pages 269-282; Molecular Carcinogenesis, July 2001, pages 152-160; and British Journal of Dermatology, February 2001, pages 267-273.)