Chemical exfoliation has such a big impact on how your skin looks and it can be used to help fade hyperpigmentation, clear acne, and prevent fine lines and wrinkles. But it can be confusing to know where exactly chemical exfoliation should occur in your skincare routine.
A question I see often is whether you should exfoliate your skin before or after using a toner.
You should exfoliate your skin (using a chemical exfoliant) directly after cleansing and before using your toner.
Keep reading for the reason why this is the case and some other tips to help you avoid making common exfoliating mistakes.
What Do Chemical Exfoliants Do? The Benefits You Should Know About
As we go about our lives, something kind of gross is occuring on the surface of our face.
Skin cells don’t live forever, and as they die, they build up on the surface of our skin. Dirt, oil and old makeup also gets left behind with these dead skin cells and if we don’t exfoliate – this build up ends up clogging pores and making our skin look dull and older than it is.
Using a chemical exfoliant helps to shed away these dead skin cells and keeps pores from becoming clogged. This has many benefits for your skin, including:
- Brightening your skin
- Lightening unwanted hyperpigmentation and evening out general skin tone
- Smoothing out rough textured skin
- Lightening acne blemishes and preventing future breakouts
- Increasing production of collagen and elastin
- Minimizing pore size
- Helping other skincare products and ingredients to absorb better and penetrate deeper into the skin, and
- Decreasing the appearance of fine lines and wrinkles
How Do Chemical Exfoliants Work?
Unlike physical exfoliation, which can often be abrasive and quite harsh for the skin, chemical exfoliation involves using one or more chemical compounds to gently break up the bonds between dead skin cells – allowing the skin to naturally shed its dead cells – revealing new and healthier cells in their place.
There are several types of chemicals which can be used as exfoliants on the skin, and these are broken up into two main categories: alpha-hydroxy acids (AHAs) and beta-hydroxy acid (BHA).
Alpha-hydroxy acids are water-soluble and their molecular size is smaller than that of beta-hydroxy acid, which means they can effectively get between layers of dead skin cells, however they cannot penetrate pores. AHAs used in skincare products include:
- Glycolid acid (the most common and derived from sugar cane and sometimes other plants with high sugar content)
- Lactic acid (commonly derived from milk, but alternative vegan sources include fermented corn starch, beets, and other sugar-rich foods)
- Citric acid (derived from citrus fruits)
- Mandelic acid (derived from bitter almonds and the most suitable AHA for sensitive skin due to it’s larger molecular size)
- Malic acid (derived from apples and pears), and
- Tartaric acid (derived from grapes)
There is only one true form of beta-hydroxy acid, which you have likely heard of before: salicylic acid.
Salicylic acid is actually a naturally occurring hormone produced by plants as an environmental or pathogenic stress defense mechanism. It can be isolated in small amounts from the bark of willow tree, however it is also produced commercially using dry sodium phenoxide and carbon dioxide.
Unlike AHAs, BHA is oil-soluble and can therefore penetrate deep inside pores to clear out any gunk.
Can I Use A Physical Exfoliant Instead? Are Chemical Exfoliants Better?
Physical exfoliation involves physically (or “mechanically”) sloughing away dead skin cells from the surface of your skin. It can be achieved using various tools (such as motorized dermabrasion sponges) or skincare products containing rough material (such as face scrubs containing ground up nut shells).
Chemical exfoliants are generally considered better for your skin as they don’t require any rubbing. Oftentimes, physical exfoliation can lead to skin irritation due to excessive abrasion (especially when products containing ground up nut shells or fruit pits are used).
Also, chemical exfoliants offer a more even exfoliation and are able to penetrate the skin for deeper exfoliation too. Products containing chemical exfoliants are usually leave-on products and are formulated with hydrating or soothing ingredients.
Korean chemical exfoliating products to try:
- COSRX – AHA 7 Whitehead Power Liquid (a cult favorite: contains natural AHA and 7% glycolic acid)
- COSRX – BHA Blackhead Power Liquid (another cult favorite: formulated with 4% betain salicylate, a gentler form of salicylic acid)
What Do Toners Do? Does Your Skin Actually Need Them?
Toners are often viewed as a type of skincare product you don’t really need in your routine. This may be because they just look like water and the effect they have isn’t visibly noticeable right away.
However, toners are hugely popular in Korea and Japan (where they are a staple in skincare routines) and they have a number of benefits for the skin, including:
- Balancing the skin’s pH after cleansing and exfoliating, which helps to maintain a healthy moisture barrier
- Priming the skin to more effectively absorb subsequent skincare products (such as serums and moisturizer)
- Hydrating and soothing the skin (to help relieve dry, sensitive or acne-prone skin)
Korean and Japanese toners are very different to Western toners!
Instead of being used to remove excess oil and debris from your skin (using astringent and very drying ingredients), Korean and Japanese toners are rich in hydrating, soothing, brightening and anti-aging ingredients, including:
- Hyaluronic acid and/or sodium hyaluronate
- Green Tea (Camellia sinensis) leaf extract
- Licorice (Glycyrrhiza glabra) root extract
- Dipotassium glycyrrhizate (main active constituent of licorice root)
- Rice extract or rice ferment filtrate
- Centella asiatica extract
- Madecassoside (main active constituent of Centella asiatica)
- Aloe vera or Aloe barbadensis extracts
- Adenosine, and
- Lots of other natural extracts – especially those used in traditional Chinese medicine
- The 4 Best Korean Hydrating Toners
- Fading Hyperpigmentation With Licorice Root Extract (Does It Actually Work?)
Korean toners to try:
- Etude House – Soon Jung pH 5.5 Relief Toner (a fragrance-free low pH toner formulated with panthenol and madecassoside – fantastic for sensitive and acne-prone skin)
- I’m from – Rice Toner (a fragrance-free brightening and hydrating toner formulated with 77.78% Goami (rice) extract – great for dry or dull, irritated and aging skin)
- Isntree – Green Tea Fresh Toner (My current favorite! A fragrance-free toner with so many beneficial ingredients: 80% green tea extract, Centella asiatica extract, hydrolized hyaluronic acid, dipotassium glycyrrhizate and beta-glucan. This toner is great for oily and acne-prone skin)
Why You Should Exfoliate Before Using A Toner
As I mentioned earlier, chemical exfoliants contain alpha-hydroxy acids and beta-hydroxy acids which work by breaking up the bonds between dead skin cells and removing sebum and other gunk from within pores.
An easy way to remember that you should exfoliate BEFORE using your toner, is to think of exfoliating as an extension of cleansing (because you’re in effect dissolving dead skin cells, sebum, dirt and other residues from your skin).
You wouldn’t want to cleanse your skin, apply a toner (which hydrates your skin and returns your skin’s pH to an optimal range), and then in effect “cleanse” again when you apply your exfoliating product.
Chemical Exfoliants Are Only Effective Within Certain pH Ranges
Another important thing to mention about exfoliating acids is that they are all pH-dependent, which means they require a certain pH range to be effective on your skin.
A pH between 3 and 4 is considered optimal for both AHAs and BHA to be effective on the skin.
AHAs and BHA would actually be most effective if formulated in a solution with a pH below 2. This is because of the chemical nature of exfoliating acids – the lower the pH of a solution containing AHAs or BHA, and the higher the concentration of “free” acid available to work its magic on your skin. However, solutions with such a low pH can cause serious burns.
On the other hand, the higher the pH of an exfoliating product and the higher concentration of exfoliating acids is needed for it to be effective on your skin.
Why does the pH of your exfoliating products determine in which order you apply your skincare products? Because the pH of most toners is above 5.5. You therefore want to apply your toner after you have applied your chemical exfoliant as toners will increase the pH of your skin to a range that will leave AHAs and BHA ineffective.
How Long Should You Wait After Applying Your Chemical Exfoliant?
Unfortunately, there is currently no scientific data to suggest whether wait times are needed after applying chemical exfoliants. This is because most scientific trials that study the use of exfoliating acids focus on concentrations and other parameters that aren’t practical for the types of skincare products we use at home.
Therefore it’s currently not agreed among dermatologists whether a wait time is required between applying chemical exfoliants and subsequent skincare steps.
However, many people do like to wait 20-30 minutes after applying their exfoliating product before moving on with the remainder of their skincare routine to ensure that:
- The chemical exfoliants have enough time to absorb into the skin, and
- The pH of the skin is at an optimal range for exfoliating acids to work
On the other hand, some people like to proceed with the next products in their skincare routine to prevent their skin from getting too dry.
It’s really a personal preference and I recommend seeing what works best for your skin.
How Often Should You Exfoliate Your Skin?
The average person loses up to 500 million skin cells per day, so dermatologists recommend that you exfoliate your skin 2-3 times per week to achieve smooth and glowing skin.
However, if you have sensitive skin or are only just starting to use exfoliating products, you shouldn’t exfoliate more than 1-2 times per week.
Not only does your skin type affect how often you exfoliate, but so does what types of exfoliating acids you’re using and what their concentration is. Glycolic acid is the most sensitizing AHA, while mandelic acid is gentle and fabulous for people with sensitive skin.
As a general rule of thumb, people with oily skin tend to be able to exfoliate their skin more often than those with dry or sensitive skin. But people with oily skin can over-exfoliate and cause damage to their skin barrier too – so you should regularly assess how your skin looks and feels no matter what your skin type.
How Do You Know If You’re Over-Exfoliating?
Your skin has a natural barrier who’s role is to keep water in and irritants out. This barrier is located on the outermost layer of the skin and is protected by a thin layer of lipids (called the acid mantle).
Exfoliating too often can damage the skin’s moisture barrier. When this happens, your skin will have difficulty maintaining the moisture levels it needs, leading to a range of skin issues.
It is easy to tell if you are over-exfoliating. Some classic signs include:
- Redness and/or inflammation
- Irritation, burning or peeling/flaking skin
- Breakouts (especially smaller pimples)
- An increased sensitivity to other skincare products or ingredients
Although a bit harder to spot, another tell-tale sign that you are over-exfoliating is if your skin feels tight, appears shiny and has a wax-like texture. This appears most noticeable on the forehead.
People often mistake this shine for a healthy glow, but what’s actually happened is that too many skin cells have been exfoliated and essential natural oils have been wiped away, exposing premature skin cells underneath. Instead of being plump and moisturized, skin will be dry, thin and waxy.
Do You Wash Off AHA/BHA Exfoliants Before Proceeding With Your Skincare Routine?
There is no need to wash off your AHA or BHA exfoliating product before you proceed with the rest of your skincare routine. These products are known as “leave on”.
There is no risk of over-exfoliation occurring as the most exfoliation occurs in the first few minutes after applying your AHA or BHA product.
BHA also has anti-inflammatory and anti-bacterial properties, while AHA is a humectant (it hydrates the skin by attracting water molecules) – these additional benefits would be lost if you washed your chemical exfoliant off after use.
However, if your chemical exfoliant leaves your skin feeling sticky or oily, you can rinse it off with warm water or gently wipe it off using toner on a cotton pad.
How Often Can You Use Toner On Your Face?
You can use your toner in both your morning and evening skincare routines every day (as long as it is a hydrating toner).
It is even beneficial to apply hydrating toners in layers for extra hydration. In Korean skincare, this is known as the 7 skin method (toners are commonly referred to as “skins” in Korea).
Do You Need To Wash Off Toner?
Toners are leave on products and therefore don’t need to be washed off. After applying your toner, you simply let it dry and then move on to the rest of your skincare routine (such as serums or moisturizer).
Washing your toner off, means you are washing off the humectants that your toner is formulated with. These humectants are important because they attract water molecules to your skin to help keep it hydrated throughout the day (or night).
Most toners also contain other beneficial ingredients that may have soothing, brightening or anti-aging properties – and washing your toner off means you would be washing these ingredients off too.
Chemical exfoliants have many benefits for your skin and they are really worthwhile including in your skincare routine.
Various types of chemical exfoliants are used in skincare products and these can be divided into two groups: alpha-hydroxy acids (AHAs) and beta-hydroxy acid (BHA). AHAs are water soluble and work on the surface of the skin to exfoliate dead skin cells, while BHA (salicylic acid) is oil soluble and can therefore penetrate deep inside pores to unclog gunk.
However, there are a few important things to know before you start using skincare products that contain exfoliating acids – mainly the order in which you apply them in your skincare routine and how often you use them.
Due to the pH-dependency of AHAs and BHAs, you should apply them after cleansing and before using your toner. You should also only exfoliate your skin 2-3 times per week to prevent skin irritation and sensitization.