The American Academy of Dermatology defines exfoliation as “the process of removing dead skin cells from the outer layer of your skin.”
Unless you have a skin pathology which results in an abnormally high turnover of cells, the epidermis (the outermost layer) regenerates every 4 weeks, on average. These shed cells can act as a barrier, preventing the absorption of products, as well as giving the appearance of dry, flaky and patchy skin.
There are two types of exfoliation methods: physical and chemical. The focus of this post will mainly be chemical exfoliation, because info on mechanical methods is widely available.
Mechanical methods include devices such as brushes, as well as products containing microbeads or granules. To each his own, however, the greatest caution when using this type of exfoliation is this: be gentle so as to avoid causing micro-trauma to the skin, which is counterproductive and encourages inflammation. Personally, I enjoy using a cleanser with gentle micro-granules about once a week.
In chemical exfoliation, there are two main players: alpha and beta hydroxyl acids. This is not the time to delve into the organic chemistry whats and hows, but if you’re a geek like me, we can indulge one another on other platforms.
Alpha hydroxy acids
These exert their exfoliative effects by weakening the bond between the cells on the skin surface. They also exert an effect on the deeper layers of the skin by stimulating collagen and moisturising matrix production. Examples include lactic, glycolic and malic acids. Glycolic acid is the most popular of these because on the molecular level, it is small enough to penetrate the skin and exert its effects. Just a caution when using any AHA products- ensure you follow them up with sunscreen, as some studies have shown that AHA use can sensitize the skin to UV damage.
Beta hydroxy acids
These exert their effects in a similar way to the AHAs- by decreasing the bond between adjacent cells. The only BHA used is salicylic acid. Its unique attribute is that unlike the AHAs, it is able to penetrate the pore, which is the so-called oil producing unit, and induce exfoliation at that level.
If you’ve used AHAs or BHAs before, you’ll notice that they come in varying concentrations. For example, salicylic acid may be in available in concentrations of 0,5, 10 even 50%, all depending on whether the product is formulated for over the counter use, or for administration by a skin care professional. According to the FDA (American Food and Drug Administration), all AHA containing products sold over the counter may not contain any more than a 10% concentration.
So, how often to exfoliate? That is often dependent on several factors: what kind of method are you using? If using chemical methods, are you using over the counter cosmetics, or are you going in for a professional peel? How sensitive is your skin?
Personally, I use the Bioderma scrub twice a week. I apply the AHA/BHA/Vit C serum every night after cleansing and toning. I specifically choose to apply the serum as part of my evening routine in order to avoid sun exposure.
So, this was just an overview into the practice of exfoliation. I hope you’ve been enlightened to make more informed choices based on your own skin type and requirements. As always, let’s engage on her or follow me on Instagram @dr_ezinhle.
Yours in a life well lived,