Acids, Enzymes and Scrubs: Which Exfoliant Should You Use And How Often?

Exfoliating Products

Updated 11/09/21. Before we talk about the different types of exfoliants and how often you should be using them, we first have to define the word itself—explaining what it means and what it does. In basic terms, an exfoliant is anything that removes dead cells from the surface of the skin, revealing a clearer, smoother, and more even-toned complexion. Exfoliants can offer both immediate and long-term results, from unclogging pores and fading post-breakout marks to lessening dryness and improving the appearance of sun spots.

However, with so many different types of exfoliants and the various forms in which they come, it can be difficult to determine which one is best for your skin. It can also be difficult to determine how much is too much. Keep scrolling to see my ultimate guide to exfoliation and learn how to exfoliate your face without overdoing it.

A Quick History of My Own Experience with Exfoliants

Back in the ’80s, when I was a teenager, I scrubbed my skin with a Buff Puff (who remembers those?). I use the word “scrubbed,” because the word “exfoliant” or “exfoliation” wasn’t even used in the skincare world yet! I would apply a harsh, overly-drying foaming face wash and then go to town scrubbing with the Buff Puff. With blemish-prone skin, scrubbing seemed like a good idea at the time. As you can imagine, my young, sensitive skin wasn’t happy; it only became more irritated.

Then, in 1992, I got my hands on a pure, 20% AHA glycolic acid gel. This was revolutionary at the time because these acids were fairly unknown (even among skincare professionals!). I’ll never forget the time I first used it. I knew it was strong because it began to tingle on my skin. Per the instructions, I kept it on my skin for 10 minutes, rinsed it off, then wiped my face with a damp washcloth. As I wiped, I noticed my skin was peeling off. I was excited, thinking, “Wow, this stuff really removes dead skin!” Come to find out, I was actually wiping off new skin cells.

Once dry, my skin began oozing badly. I developed scabs all over my face, and it took months to fade the resulting discoloration. It was a nightmare—especially since I was an esthetician, and I was expected to have perfect skin and be a role model for clients. If there was one silver lining from that experience, it’s that it taught me what NOT to do. I still use exfoliating acids to this day, and I’ve never repeated that experience.

Exfoliating Acids

How They Work…

There are two categories of exfoliating acids: Alpha Hydroxy Acids (AHAs) and Beta Hydroxy Acids (BHAs). They create a chemical reaction that lowers skin pH and dissolves and digests the “glue” that holds dry, expired cells together. To work most effectively at home, an exfoliating acid must fall within a pH range of 3-4 and be at a concentration of 5%-20%.

AHAs are water-soluble, so they don’t penetrate as far into the pores. However, they can be incredibly effective at removing pigmented cells left behind by breakouts or sun exposure, as well as giving smoothness to the skin. The most common AHAs are lactic, glycolic, malic, mandelic, and tartaric acids. (Citric acid is also an AHA, but it’s not technically an exfoliant; it is used as a pH adjuster.)

BHAs, on the other hand, are oil-soluble, so they can penetrate deep to lessen clogged pores and remove dead cells that can lead to blackheads and breakouts. There are two BHAs commonly found in skincare—salicylic acid and betaine salicylate. Another one, called butyric acid, is found in the odor that rancid butter emits, so it’s not something you would want to use on your skin! That’s just a fun little fact I learned from a cosmetic chemistry class I took at UCLA.

Note: If you’re pregnant, consult your doctor before using BHAs.

They Suit…

Exfoliating acids are best for anyone who has clogged pores, blackheads, breakouts, dryness, flakiness, fine lines, wrinkles, large pores, dullness, discoloration, or rough texture. Anyone can safely use exfoliating acids, even those who have sensitive skin, such as rosacea!

What I love most about exfoliating acids is that they do the work for you. In other words, you don’t have to rub and tug at the skin. As long as you’re using a formula with a proper pH and percentage that is appropriate for your skin type, you can put it on and let it work its magic with no fuss or effort on your part.

Note: A tingling sensation may or may not occur when you apply an exfoliating acid. This is not an indicator of product efficacy. Instead, it’s an indicator of how your skin’s barrier is acting at the time of use. If your skin tingles, it could mean your barrier is compromised. (Read up on how to fix a damaged moisture barrier). In fact, it’s very common for the tingling sensation to stop after a month or so of use. People say, “I don’t feel like it’s working anymore because I can’t feel it sting like I did when I first started using it.” The truth is exfoliating acids, when not overused, can actually aid in fixing your skin’s moisture barrier, which explains why it can become less reactive with continued use. You don’t need the pain to gain!

You Can Find Them In…

  • Cleansers: Exfoliating acids can make a great addition to a cleanser. When massaged over the skin, they can dissolve dry, dead skin cells. Since cleansers are rinsed off fairly quickly, though, you won’t get a lot of exfoliation. Make sure to also use a leave-on product for maximum efficacy. Recommended Renée Rouleau product: AHA/BHA Blemish Control Cleanser.
  • Toners: These provide a quick hit of light exfoliation, but I don’t believe they replace the need for a leave-on product, such as a serum or cream. This is because water-based products evaporate quickly and won’t penetrate very deep—even if you feel an immediate tingling sensation. Of course, all formulas are different and I’m generalizing here. I still don’t recommend using an exfoliating acid toner along with an exfoliating acid serum or cream. This combination could be too strong. Recommended Renée Rouleau product: Rapid Response Detox Toner.
  • Serums: These are formulated to penetrate the skin’s surface most effectively. They are my absolute favorite way to thoroughly saturate cells to get the best results. Serums enter the epidermis when applied to the skin and are followed with a moisturizer. Due to their viscosity, they can work for a longer period of time than acid-based cleansers and toners do. Recommended Renée Rouleau products: Pro Results Power Serum, BHA Clarifying Serum, Ultra Gentle Smoothing Serum, Pore + Wrinkle Perfecting Serum.
  • Creams: AHAs formulated within a cream texture can still be effective for surface exfoliation. However, when it comes to BHAs, creams with salicylic acid will not be very effective. I see fewer and fewer acid-based face creams these days since serums are much more efficient.
  • Masks & Peels: Like serums and creams, masks hug the skin due to a thicker viscosity. They typically say on the skin for 5-15 minutes, which makes them good for providing quick results. Recommended Renée Rouleau product: Triple Berry Smoothing Peel.
  • Eye Products: Yes, you should exfoliate the area around your eyes! Recommended Renée Rouleau product: Overnight Eye Serum.
  • Body products: Some specialized body products contain AHAs to smooth skin and manage dryness. Some of them can help manage a skin condition called Keratosis Pilaris (KP). Recommended Renée Rouleau product: Smoothing Body Serum.

Exfoliating Enzymes

How They Work…

Enzymes are fruit-derived and absent of acids or grains. This means they can offer a gentler, no-sting exfoliation, which is very helpful for sensitive skin types. Pineapple, pumpkin, pomegranate, and papaya are the most common fruit enzymes used in skincare products. They work by dissolving and digesting the protein found in dead skin cells, thereby revealing smoother skin.

Both exfoliating acids and exfoliating enzymes dissolve dry skin cells, but there are a few main differences in how they work. Enzymes work more on the surface, while acids slip deeper into the skin’s surface. Water activates enzyme peels, and they work more slowly to digest cellular buildup. So, apply them to damp skin and leave them on for 15-20 minutes. Acids, on the other hand, can be applied to dry skin. When used in a peel, they can work in as little as five minutes.

They Suit…

Any kind of exfoliation can improve skin conditions like clogged pores, blackheads, blemishes, dryness, flakiness, fine lines, wrinkles, large pores, dullness, and discoloration. With that being said, anyone who can’t tolerate exfoliating acids will find enzymes a particularly good option.

You Can Find Them In…

You can find exfoliating enzymes in the same types of products that you can find exfoliating acids. Sometimes, a single product will use both of them. As for an enzyme exfoliator that I personally use and recommend, it’s the Renée Rouleau Dual Enzyme Softening Peel. I designed it specifically for sensitive skin. It uses papaya and pineapple enzymes to smooth away dry skin cells and help fade discoloration.

Physical Exfoliants

How They Work…

Physical exfoliants, such as face scrubs, cleansing brushes, and washcloths, have a slightly abrasive texture that when massaged across the skin, manually slough off dry, dead skin cells. This type of exfoliant complements exfoliating acids and enzymes. Whereas acids and enzymes dissolve and loosen dead cells, physical exfoliants can actually lift them up and away. That’s why I suggest using a physical exfoliant one to two times per week, whether it’s a scrub, cleansing brush, razor, or washcloth. (If you’re not using any other exfoliants, you can use a physical exfoliant up to five times per week.)

They Suit…

All skin types can use physical exfoliants, even sensitive skin. The key is to use very light pressure. If you’re using a face scrub, let the beads or particles glide over the skin. People often make the mistake of pushing too hard, which can result in redness and irritation.

You Can Find Them In…

As I said before, something as simple as a washcloth can be a physical exfoliant. However, the one I recommend is the Renée Rouleau Mint Buffing Beads. This product uses perfectly-round jojoba beads that roll over the skin to gently exfoliate it. Jojoba beads are far superior to any other naturally-made grain like apricot kernels, sugar, salt, and natural seeds/shells.

There’s one more thing I want to mention about physical exfoliants and face scrubs in particular. They work very well to keep the skin on the neck smooth. When exfoliating the neck area, make sure to look upwards so the skin on the neck is nice and taut. Exfoliate the area three times a week at night and be sure to follow with a neck cream to nourish the fresh cells.

How Often You Should Exfoliate

I suggest using an exfoliant no more than five times per week at night. When it comes to making recommendations for the skin, it’s always hard to generalize for all skin types but for most, four to five times per week is plenty. Whether that’s in the form of a facial scrub, serum, mask, or whatever, you’ll want to stay within this range. If you don’t stay within this range, you could run the risk of over-exfoliating. Seeing as your skin needs a certain number of protective layers to stay healthy and retain moisture, over-exfoliating may be harming your skin more than you realize!

What Can Happen If You Exfoliate Too Often

  • A damaged moisture barrier, resulting in dehydration, flaking, redness, and inflammation
  • Dryness, as a result of moisture seeping out of your cells
  • Advanced aging due to chronic and prolonged inflammation
  • Destruction of healthy skin cells
  • Stimulation of melanin activity, possibly resulting in hyperpigmentation
  • Irritation and stinging sensation as a result of damaged barrier function

If you’re experiencing any of these things, listen to your skin and pull back on exfoliation.

Disclaimer: Content found on and, including text, images, audio, or other formats were created for informational purposes only. The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website or blog.

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