Using Acids To Exfoliate – All You Need To Know

It may sound counter intuitive, but using acids to exfoliate your skin is a gentler approach than using scrubs or cleansing brushes. 

As you will know, if you want your skin to have a healthy glow, exfoliating regularly really should probably be part of your skincare routine.

Exfoliation is a natural part of the skin cell cycle. It involves removing dead skin cells from the skins surface which makes way for new skin cells to generate.

As you age, this natural cycle slows down, which can lead to a build up of dead skin cells. When dead skin cells  accumulate this can make your complexion look dull.

There are two ways to get rid of the dead skin cells; mechanically by using gritty facial scrubs or chemically using acids or enzymes. 

Using acids to exfoliate will be the focus of this article. We will consider which acids are used in skincare products, how they work and whether they are safe.

Which Acids Are Used?

AHAs and BHAs are the two main forms of exfoliating acid commonly used in skincare products, so what’s the difference?

AHAs (Alpha-Hydroxy Acids) are water soluble chemicals derived from plant or animal sources. There are a number of different types of AHAs which are commonly used in the skincare industry. These include; citric and malic acid (from fruits), glycolic acid (from sugar cane) and lactic acid (from lactose in milk).  Research has shown that the most effective AHAs are glycolic and lactic acid and are the ones you will most commonly found in over the counter skincare products.

BHAs (Beta-Hydroxy Acid) are fat soluble acids. This is important an important difference because it means they can pass through sebum and sebaceous follicles. There is really only one type commonly used in skincare products; salicylic acid.

The best type for you to use depends on your skin type. If you have an oily or combination skin type, then BHAs will be your best choice. If you have dry skin AHAs will be a better choice. 

How Do They Work?

These chemical exfoliants work in two ways: water soluble AHAs work to remove the build-up of dead cells on the skin’s surface to reveal a brighter, smoother complexion. Fat soluble BHAs penetrating into the oil producing pores to remove build up and help clear breakouts.

A simple explanation is that the acid breaks down the “glue” that holds skin cells together, but it turns out it is a bit more complicated than that.

A Study published in the Journal of Biological Chemistry, shows that AHAs work by interacting with a membrane protein in the skin cells. They enters the surface skin cells and generate acidic conditions within the cells. This activates an ion channel in the cell’s membrane protein causing calcium ions to flow into the cell. This influx promotes cell death on the surface layers of the skin.

Research has shown that, for the best results,  AHA exfoliants containing glycolic acid or lactic acid should contain concentrations between 5% and 10% and have a pH between 3 and 4. As a rule of thumb, the higher the concentration of AHAs, the more powerful the exfoliating effects. BHAs are effective at much lower concentrations, between 0.5% and 2%. 

Although both work primarily as exfoliants, BHAs can also reduce excess oil by slowing down the production and release of sebum. They can also help prevent acne and blackheads by clearing sebum trapped in the follicular wall. The low pH also gives mild anti-bacterial properties which prevents bacteria growing in pores and producing breakouts.

Are There Any Side Effects?

If you’ve never used exfoliating acids before, you may experience minor side effects while your skin adjusts. 

Any acid can be drying and irritating if you use it at the wrong concentration or pH, or if you apply it too frequently. Common side effects are burning and itching, but these are usually temporary.

To reduce your risk of irritation, It is recommended that you use AHA products every other day until your skin gets used to them. You should also avoid products with an overall AHA concentration of more than 10 percent.

Research suggests that AHAs may make your skin more sensitive to UV light for up to a week. It is sensible to wear sunscreen daily.