Welcome to Ask a Beauty Editor, our new column in which Sarah Jacoby, SELF’s senior health and beauty editor, goes on the hunt to find the science-backed answers to all of your skin-care questions. You can ask Sarah a question at firstname.lastname@example.org.
I’m curious about chemical vs. physical skin exfoliation. What is the point of chemical vs. physical? When do I use each one, and how frequently? Also, should I be exfoliating my entire body regularly?
Hey there, Scrub. I feel ya. Like many people, harsh exfoliating scrubs were some of the very first skin-care products I tried, likely because many of them are marketed toward teens with acne. But as I got older and (maybe) a little more sophisticated about my regimen, I learned about all the other, gentler options out there.
Of course, having that many options is great, but it also creates the exact type of confusion you’re experiencing. What kind should you actually be using? And how often should you use them?
So, to start, let’s remember that there are two major categories of exfoliants: manual (physical) and chemical, Jenny Hu, M.D., associate professor of dermatology (clinician educator), Keck School of Medicine of USC, tells SELF.
Manual exfoliants include things like scrubs and brushes that physically remove dead skin cells and dirt from your face. Chemical exfoliants do the same thing by dissolving the bonds between skin cells, revealing newer, smoother skin cells underneath. Some products, like salicylic acid scrubs, are both chemical and physical exfoliants. Regularly exfoliating can help prevent acne, manage some types of dark spots, and contribute to an overall “glow.”
In general, chemical exfoliants are preferred, Dr. Hu says, because they’re gentler and less likely to cause irritation on dry or sensitive skin. People with acne-prone skin may want to choose chemical exfoliants as well, she says, because “sometimes more vigorous exfoliating in people who are acne-prone can cause more irritation,” which can also contribute to acne and trigger breakouts. That’s especially true if you have dry or combination skin that’s also acne-prone.
Those with darker skin should also know that any aggressive manual exfoliation can cause post-inflammatory hyperpigmentation (dark spots), so they should probably opt for chemical exfoliation most of the time.
If you have oily skin, though, you are more likely to be able to tolerate manual exfoliants (as well as stronger concentrations of chemical exfoliants) than other skin types. And really anyone who doesn’t have sensitive skin can experiment with using manual exfoliants sometimes and chemical exfoliants at other times—as long as you’re not using them on the same days. To be fair, people who have sensitive skin can experiment with that too, they just need to be aware that their skin is more likely to react badly, so they should do so with caution.
Regardless of the type of exfoliant, Dr. Hu recommends starting with exfoliating just once a week and seeing how your skin responds. If you can handle more, there’s no problem with going up to two or three times per week. And if you find that once a week is too intense, you can try using a gentler product or reducing the frequency to every other week.
If you notice redness, dryness, increased sensitivity, or flaking, those are signs that you’re going too hard with your exfoliating regimen and should probably back off, SELF explained previously. If you exfoliate too harshly or too frequently, you could even damage the stratum corneum, the outer layer of skin that keeps your face hydrated and protected.
With manual exfoliants it’s easy to unwittingly scrub too hard or apply too much pressure to a brush, so be sure to be as gentle as possible when using those. In fact, Dr. Hu suggests just using a gentle washcloth rather than a brush for a less aggressive manual exfoliant. And with chemical exfoliants, you can try to look for lower percentages of the active ingredient and opt for the gentler ones out there, such as lactic acid (an alpha-hydroxy acid) or any of the polyhydroxyacids (PHAs).
And what about exfoliating your body? For the majority of us, it’s optional. But if you have certain skin issues, it could be key. If you’re prone to body acne or keratosis pilaris, for instance, exfoliating with a gentle chemical exfoliator could help manage those issues. And anyone who exfoliates their body may notice smoother and brighter skin after doing so, but ultimately the benefits are mainly cosmetic.
Basically, Scrub, exfoliating is a simple process made unnecessarily complicated by the amount of choices you have. Depending on your skin type, you may find that some methods of exfoliation are too harsh or not aggressive enough. So start slow and experiment—with caution!—to find what works for you. And if you run into any issues, talk to a dermatologist about your other options.