POSTED: 9 Mar 2021

A to Z of Beauty: Exfoliating acids in skincare – AHA, BHA & PHA

A to Z of Beauty : Exfoliating acids in skincare – AHA, BHA & PHA

Exfoliation is a crucial step that helps remove dead cells and unclog pores from your skin. You can successfully exfoliate using physical or chemical exfoliants. By far, the safest and most versatile technique is chemical exfoliation using exfoliating acids! If you are unsure of where to start, read our guide for everything you need to know about how to exfoliate your face with acids.

How do you use exfoliating acid?

Once you hear acids, you might think of them as the last things you would want on your face. However, exfoliating with acids can be a great way of smoothing and brightening your complexion. Some of the key benefits of using acid exfoliants include brightening dull skin, treating hyperpigmentation, smoothing lines and wrinkles as well as improving acne and scarring. Even better, some exfoliating acids can stimulate your skin to produce more collagen and hence improve your skin’s plumpness and elasticity. When exfoliating with acids, you need to understand how they work so that you can choose the best one for you.

Exfoliating acids can be easily purchased from any reputable skincare outlet or drug store. They can also be very easily integrated into your skin and used either in the morning or at night. The best way to use them is as a toner or lotion after cleansing and before serums or moisturising. You should, however, avoid going overboard with exfoliating acids. That’s because these acids help resurface your skin by removing the upper layers of dead skills. As such, excessive usage can strip the skin off its protective barrier. As a result, this can lead to dryness, sensitivity, and irritation. Consider using exfoliating acids only once or twice a week if you have sensitive skin. You should also understand that your skin may also become even more vulnerable to sun damage. As such, you should always wear sunscreen during the day even in doors.

Types of Exfoliating Acids

There are several types of exfoliating acids and they come in different strengths. The weaker options are available over the counter in regular skincare and are safe to use at home. Whilst the stronger ones are only available as an in office chemical peel treatment by a medical professional. Regardless of strength, exfoliating acids work by breaking the glue or bonds that that hold dead skin cells together. As a result, the skin sheds the top layers more quickly to reveal the newer skin underneath.

Regular use of exfoliating acids can lead to an even tone, smoother skin, unclogged pores, and reduce ageing signs. The three main types of acid exfoliants in skincare are Alpha Hydroxy Acids (AHA), Beta Hydroxy Acids (BHA) and Poly Hydroxy Acids (PHA).

AHA include Malic acid, Citric acid, Lactic acid and Glycolic acid. These acids can either come from fruits or synthetic production. They can dissolve in water, thus easily working on the skin surface to improve the texture. Some of the commonly used alpha hydroxy acids are lactic and Glycolic acid.

BHA are oil-soluble, thus they can also penetrate your pores. They can also work on your skin surface to provide a better texture. Since they are deeper working acids, they help remove acne and unclogging your pores. The most famous and popular BHA is salicylic acid.

PHA are similar to AHA but they have larger molecules that prevent them from going deeper into the skin. As such, these are less irritating to skin when compared to alpha-hydroxy acids. They also attract natural moisturising factors and hence have hydration benefits. Some of the commonly used PHA include lactobionic and gluconolactone acid.

Differences between AHA and BHA

Two of the most commonly used exfoliating acids are alpha-hydroxy acids (AHA) and beta hydroxy acids (BHA). These acids can be found in a wide array of products including masks, peels, scrubs, moisturizers, toners and even cleansers.

Both AHA and BHA help with skin exfoliation and help stimulate collagen production. AHA are made from sugary fruits and are water-soluble acids. They work by removing layers of dead cells from the surface of your skin. BHA, on the other hand, are oil soluble. They can get deep into the pores, unlike alpha-hydroxy acids, and remove excess oil as well as any dead skin cells clogging pores.

Which acid is best for exfoliation?

Alpha hydroxy acids and in particular glycolic acid, are the gold standard. This is because they have small molecules which can go deeper into the skin. As such they are great for ageing or dry skin, hyperpigmentation, wrinkles or fine lines and skin texture. However, people with sensitive and extremely dry skin should either use mild AHA like lactic acid or opt for PHA instead. You should also gradually introduce AHA to your skin to prevent skin irritation and only use low  concentrations designed for at home skincare. In the case of glycolic acid this is usually 5-10%.

If you have oily skin or acne prone skin, then BHA are usually the best solution. That’s because they are oil soluble and can hence penetrate dee into pores to unclog them. They can also help regulate sebum production. As such, they can help with breakouts, enlarged pores as well as give the benefits of exfoliation that AHA provide.

For people with combination skin, you may use AHA, BHA, PHA or any combination of these.

As you have probably guessed we’re in love with exfoliating acids. Just remember that with any skincare ingredient or product you will get the best outcome if you do your research! Make sure you know your skin type, skin concerns and have clear treatment goals. This will help you choose the best exfoliating acid for you. Also start slowly and follow the instructions on the product! Whilst exfoliating acids are great, you should always approach active skincare with care. This will protect you from any severe allergies or reactions. Above all, be patient and consistent!

What next?

Head over to our Instagram (@cityskinclinic) for more tips on skincare and professional skin treatments.

If you’re looking for skincare advice then head over to our skincare routines page.

Don’t forget to check out our Obagi virtual skin clinic for more about our professional at-home skin treatment kits.

To learn more about skin boosters and hydraters check out our Profhilo treatments in London.

Authored by:

Dr Amel Ibrahim
Aesthetic Doctor & Medical Director
Founder City Skin Clinic
Member of the Royal College of Surgeons of England
Associate Member of British Association of Body Sculpting GMC Registered - 7049611

Connect with us

  • Facebook Logo
  • Twitter Logo
  • Instagram Logo
  • Pinterest Logo
  • YouTube Logo
  • LinkedIn Logo

Start Your Online Consultation

The journey to great skin starts here. Start your online consultation for personalised prescription-strength skincare.

Start Consultation