We sometimes get asked why we don’t have higher concentrations of hydroxy acids in our exfoliating serum (Smooth Serum) like some of our competitors. And then other times we get asked whether it’s safe to exfoliate everyday. 

To understand more – let’s dive in and find out. 

Exfoliation has been around since the ancient Egyptians and its abilities to lighten skin (particularly freckles) has been known since the late 1800’s. It was only 100 years later in the 1980’s that the popularity of exfoliation using chemical peels became popular.

Exfoliation increases the sheen of our skin and decreases skin roughness by removing dead skin cells on the surface of the skin. And while that’s nice, depending on type and (in the case of chemical exfoliation) concentration of ingredient, it can do much more including reduce hyperpigmentation, stimulate Collagen growth (which reduces wrinkles and fine lines), help the skin retain more moisture, help clear acne and treat certain skin conditions like Psoriasis.

The general rule is that the more intense or deep the treatment, the better the result.

But first a little intro on exfoliation and the options available

Exfoliation is the process of removing skin cells, usually the oldest dead cells, from the surface of the skin. At home there are two ways of doing that, using chemical exfoliants such as Glycolic, Lactic or Salicylic Acids which loosen the bonds between dead skin cells allowing them to be washed away, or physical exfoliants which mechanically scrub dead skin cells away.

Your doctor will have access to other forms of physical exfoliators, like micro and hydradermabrasion (blasting your skin with little particles to remove the outer layer of the skin), or lasers and radio frequencies which not only remove the outer layer of the skin but also injure the skin in order to generate a healing response, or more intense chemical peels than those you can use at home. These more intense exfoliation techniques tend to get better results, but also usually come with more discomfort and usually require some “downtime” (up to 10 days) for the skin to recover from the procedure.

Given the more intense exfoliation results in damage which is visible, at least in the short term, it is reasonable to ask whether the same may be true of less intense exfoliation that we do at home. And recently, specific concerns around exfoliation have centred on skin damage from harsh face scrubs and long term risks from the use of daily alpha hydroxy acids (like Glycolic acid).

So let’s dive in and have a look.


Physical exfoliators

There is very little in the way of peer review journal articles investigating the safety of physical exfoliants like scrubs. There are quite a number of dermatologists who have been quoted talking about the risks of micro tears from the use of rough facial scrubs. And in a class action brought against the maker of a facial scrub, based on expert testimony, the judge did accept that rough exfoliators can cause micro tears which can result in an impaired barrier function and a number of adverse medical problems conditions (worse acne, infection and wrinkles). And medically, causing repeated damage to the skin through abrasion (eg. using rough scrubs) will result in inflammation which over time will accelerate skin ageing.

As for the more aggressive physical exfoliation methods (like microdermabrasion), while not appropriate for more sensitive skin and risking changes in pigmentation of darker skin colour, none of the published studies find lasting adverse effects (beyond the initial irritation). But all the studies are very short term – so it’s difficult to reach a conclusion there.

There is very little indication that using gentle physical exfoliation has any real downside. It’s just hard to measure “gentle” (It’s not like sandpaper where you can go to the checkout counter and ask for a particular size grit). And many of the gentle alternatives aren’t environmentally friendly (eg. plastic microbeads).


Chemical exfoliators

In the 1980’s deep chemical peels using high concentrations of AHA’s and other exfoliating ingredients became popular. Apart from their ability to resurface the skin, their anti-ageing effects are not only obvious but backed by a significant amount of evidence

But apart from the initial irritation and peeling and the risk of long lasting pigmentation changes for people with darker skin colour, other concerns started to emerge. Some users started reporting that after a number of high strength chemical peels, their skin looked older and no longer benefited from chemical peels. We’re not sure that this is correct, but for some, there is a plausible way that this might have been the case. 

High concentration peels have (subsequently) been shown to increase the sensitivity of the skin to UV damage (ie. They are phototoxic) and consequently increase the risk and impact of UV damage. In fact concentrations as low as 10% Glycolic Acid have been shown to increase sun-sensitivity. And we know that UV exposure is the primary cause of premature ageing. So it may have been that the increased UV sensitivity led to premature ageing despite the anti-ageing benefits of the AHA peels.

But – and this is really fascinating – lower concentrations of Glycolic Acid have been shown to be photoprotective ie. in addition to the anti-ageing and exfoliation benefits they bring, they also decrease the risk of sun-sensitivity and UV induced skin damage! 

The tipping point seems to be a concentration of around 5% Glycolic Acid, (with lower concentrations being photoprotective). And pH also plays a role with a low pH increasing sun sensitivity independent of concentration (a pH above 3.5 is recommended).

So, is over exfoliating a thing? The clear answer is yes! 

But in the case of low concentration Glycolic Acid exfoliation, we know the opposite is true. It’s why we formulated ESK’s Smooth Serum using 3% Glycolic Acid and 1% Lactic Acid and have formulated it with a pH of 3.7 – but that’s what you would expect if you’re following the evidence.


An Alpha Hydroxy Acid exfoliating serum for use at night. This potent serum renews the skin by promoting skin cell turnover. The result: a more balanced and smoother skin and a more even skin tone. For skin renewal of all skin types. Also helps regulate oily skin.

Evidence Skincare Smooth Serum

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