Written By Mira Aguirre
Article Summary
- The history of exfoliation
- The skin barrier and the shedding of dead skin cells
- Exfoliant categories and how they interact with our skin
- Should you hydrate or exfoliate?
The History of Exfoliation
Beauty rituals and caring for our skin is a practice that began in ancient times and exfoliation is no exception. The ancient Egyptians used pumice stones for mechanical exfoliation and may have even used wine or sour milk for chemical exfoliation. Exfoliating our skin is something you can find in almost every culture, from Ayurvedic brushes in India to a gentle exfoliation technique called “gommage” in France. The idea is to remove dull or rough skin and improve skin appearance.
In the 21st century, we know more about our skin than ever before. Let’s take a deep dive into what exfoliation is on a scientific level, the different ways we can exfoliate, and how to tell if your skin needs exfoliation.
The Skin Barrier
Imagine your skin barrier as a brick wall. Skin cells called corneocytes are the “bricks”, and lipids, or natural fats, act as the “mortar” between them to seal everything up. A wall is also a great visual because as the name suggests, the skin barrier serves as a barrier between us and our environment. A healthy skin barrier is needed to keep water in and keep the bad things out.
There are also corneodesmosomes that anchor our skin cells together and when it’s time for dead skin cells to be shed, our skin has little enzymes that eat away this “glue.” Think of it as a way to replace old, crumbling bricks with new ones - though a better analogy would really be removing the dried, outer layer of the onion to expose the fresh, juicy layers beneath
When your skin barrier is damaged, it can’t keep your skin hydrated as well, since water more easily evaporates through the gaps in your skin cell bricks. Remember those enzymes that eat away the intercellular glue to help your dead cells shed normally? Those enzymes require a certain water level, so if your skin can’t hold onto water, it also can’t shed its dead skin cells as well. Dry, flaky skin is a sign that there is barrier impairment and dehydration occurring in our skin. Because it’s the uppermost layer of our skin and exposed to our environment, the most common barrier disruptors are soaps and harsh surfactants, low humidity, cold weather, and over-use of irritating topicals and exfoliants. In addition to being flaky, the skin can also feel tight, irritated, extra-sensitive, or hyper-oily.
What are exfoliants or how do they work?
Exfoliants in skincare are used to break down the connections between skin cells so that they shed faster, exposing the newer skin cells underneath. This applies not just to the dead cells on the outer surface of your skin – your pores are also lined with skin cells that can get stuck and build up, so some exfoliants can help clear out clogged pores as well.
Exfoliants can be categorized in a few different ways:
- Mechanical vs chemical. Scrubs and brushes manually remove skin cells while chemical exfoliants allow skin cells to shed by breaking down those corneodesmosomes I discussed.
- Keratolytic vs comedolytic. Keratolytic agents are chemical exfoliants that target the skin cells in our skin barrier and include alpha hydroxy acids and urea. Comedolytic ones target the skin cells within our pores and include salicylic acid and benzoyl peroxide.
- Level of exfoliation. Weekly masks and peeling pads often use a higher concentration for more significant results but are formulated for more infrequent use. Meanwhile, gentler exfoliants are designed for more regular use.
Did you know? Mandelic acid is an interesting exfoliant because its molecular shape is basically a glycolic acid molecule combined with the benzene ring from salicylic acid. This allows it to exfoliate both the skin surface and the pore lining while the larger size also means it’s very gentle. Check out Stratia’s Soft Touch AHA here.
Depending on which exfoliant you use, they can be helpful in targeting specific skin concerns like texture, clogged pores, and hyper-pigmentation as well as aging skin. But there’s also a popular belief online that everyone needs to exfoliate… and that your skincare won’t penetrate if you don’t. So let’s find out: do you really need to exfoliate?
Hydration VS Exfoliation
“Skincare” means to literally care for our skin. That doesn’t just mean cosmetic concerns (which are also valid) but also supporting skin health. This allows our skin to function optimally and do its job in protecting us.
Above, I explained how the skin actually has its own natural exfoliation process called desquamation. This means that as long as desquamation is occurring normally, we don’t need to exfoliate. Cleansing can gently encourage dead skin cells to shed and retinoids can also normalize skin shedding if it’s disrupted by age or clogged pores. If you’re not experiencing any dullness or flaking, you probably don’t need to add an exfoliant since your skin it taking care of it just fine on its own.
Exfoliation can help with dull, flaky skin – sometimes. It won’t help if the flakiness is caused by a damaged moisture barrier, as I described above.. It can exacerbate the problem, further impairing your skin barrier function and leading to even flakier skin. If you think your moisture barrier might be damaged, focus on hydration rather than exfoliation.
Tips for Restoring Hydration:
- Use a gentle cleanser like the Stratia Velvet Cleansing Milk which has mild cleansing agents that won’t further disrupt barrier function and cause moisture loss
- Hydrate the skin with a humectant rich serum like our Rewind which will grab onto the water that is being lost and keep it in the skin
- Finish with a moisturizer like Lipid Gold to both prevent moisture from evaporating and restore barrier function with ceramides, fatty acids, and cholesterol
Okay, so when should you exfoliate? Exfoliants are excellent for targeting more specific skin concerns not addressed by a basic skincare routine. And if restoring skin hydration and barrier function fails to address congestion or dull skin, a very mild exfoliant can be carefully added in after to assist in getting those dead skin cells to shed.
When to add an exfoliant:
- Your skin looks dull, and it’s not caused by a damaged moisture barrier
- You have clogged pores or congested skin (go for a keratolytic like salicylic or mandelic acid)
- You want to fade hyperpigmentation and stimulate collagen production (go for an AHA rather than BHA)
References:
https://www.dermascope.com/resources/exfoliation-from-ancient-times-to-modern-day-aesthetics
Mira is a skincare educator, blogger, and the content creator behind Skin Science by Mira and The Skincare Forum on Facebook. While skincare keeps her busy, she’s also pursuing her degree in Nursing and loves to spend her free time hiking. As a content writer for Stratia Skin, Mira shares her evidence-based approach to skincare topics and a passion for making science accessible.
