What you need to know about AHA, BHA and PHA in skincare

What are AHA, BHA and PHA?

AHA, BHA and PHA are exfoliating acids often used in skincare. The acids occur naturally in, for example, fruit, milk and tree bark - and in skincare products they act as active ingredients with unique properties. 

What makes acids special is that they work with the skin’s cell renewal. In skincare, products containing AHA, BHA and PHA acids are also called chemical peels because they gently exfoliate the skin’s outermost layer. This form of peeling differs from physical exfoliation, such as face scrubs, which exfoliate using physical grains.

For a chemical peel to exfoliate the skin effectively, the product’s pH is typically between 3 and 4. This allows the acids to dissolve the fine outermost layer of skin, making it easier for your skin to renew itself and removing dead skin cells.

AHA

• Stands for Alpha Hydroxy Acid
• Two of the most popular AHA acids are lactic acid (lactic acid) and glycolic acid (glycolic acid).
• Derived from natural sources such as fruit and dairy products
• Works primarily on the skin’s surface to bind moisture, even out skin tone and reduce fine lines
• Supports the skin’s natural cell renewal
  

BHA

• Stands for Beta hydroxy Acid
• One of the most popular BHA acids is salicylic acid (salicylic acid).
• Is an oil-soluble acid
• Originally derived from the bark of willow trees
• Works in the skin’s pores, penetrates deeper and helps reduce oil, sebum and blemishes

PHA

• Stands for Polyhydroxy Acid
• Two of the most popular PHA acids are gluconolactone and lactobionic acid.
• Is a water-soluble acid
• Often derived from fruits such as grapes and sugar cane
• Works on the skin’s surface, gently exfoliates, helps reduce dead skin cells and adds moisture

What is the difference between AHA, BHA and PHA?

AHA, BHA and PHA acids work differently in the skin. While AHA and PHA acids work on the skin’s surface to moisturise and renew, BHA acid works deeper down to cleanse and reduce blemishes. PHA acid is gentle and also adds extra moisture, making it suitable for more sensitive skin.

AHA, BHA and PHA work effectively together, which is why they are often used in combination in skincare products such as peeling masks. Even so, it is important to know your skin and its needs, as not all skin types tolerate all acids equally well.

Glycolic acid and lactic acid: the two most commonly used AHA acids

Glycolic acid (glycolic acid) loosens dead skin cells, leaving skin smoother and glowing. It is the smallest of the AHA acids and therefore easily penetrates the skin’s outermost layer.

Lactic acid (lactic acid) exfoliates in the same way. Lactic acid is also found in the skin’s own moisture system, which is why it is often used in care for dry and hard skin, for example on the feet.

	Glycolic acid	Lactic acid
Makes skin	Smoother, with a glow and a more even tone	Smoother and softer
Often found in	Toner, peeling masks and body lotion	Peeling masks, body lotion and foot cream
At ECOOKING	See products with glycolic acid	See products with lactic acid

Should I choose AHA, BHA or PHA for my skin type?

You need to know your skin type before you start using AHA, BHA and PHA acids in your skincare. Whether your skin will benefit from a combination of several acids, whether you need them individually, or whether your skin is too sensitive for them varies.

Always remember to listen to your skin’s signals and watch for irritation – whatever your skin type.

You can use AHA, BHA and PHA together if you:

• Have oily skin or struggle with blemishes or acne.
• Have mature skin that is generally resilient and less sensitive.

In these cases, the acids will work together to give you healthier and more balanced skin. AHA and PHA will work to improve skin texture, moisture and elasticity, while BHA will cleanse the pores and balance natural oils. Together, they will reduce fine lines, enlarged pores, pigmentation spots, age spots, strawberry skin and blemishes, among other things.

You should only use AHA and/or PHA if you:

• Have dry skin or dehydrated skin.
• Have sensitive skin or skin damaged by, for example, the sun. 

Here, AHA and PHA help bind and retain moisture and protect the skin from irritation. By leaving out BHA, your skin receives a gentler treatment focused on moisture, renewal and elasticity. PHA is particularly suitable for more sensitive skin, as it gently exfoliates while adding moisture.

You should only use BHA if you:

• Have oily skin with a lot of excess sebum production and clogged pores. 

In this case, your oily skin needs to be freed of excess sebum so that clogged pores can breathe again. AHA and PHA can also be used on oily skin, but BHA typically has the most targeted effect on clogged pores.

You should be careful with AHA, BHA and PHA acids if you:

• Have very sensitive skin or young skin.

As a rule of thumb, you should be careful with acids in your skincare if you have sensitive or young skin. If in doubt, you can give your skin a break and care for it with milder skincare products.

If you have slightly sensitive or combination skin, you can start with a low concentration - especially with AHA and BHA - and work your way up if your skin allows it. PHA can often be better tolerated, but still start carefully.

Read also: How to get rid of blemishes and spots

3 helpful tips: What to keep in mind when using acids in skincare

Before you start using AHA, BHA and PHA acids in your skincare, it is important to fully understand how the acids work and how best to use them in your daily routine.

1. Can I use acids every day? Some acids can be used daily - it depends on the concentration and the type of acid the product contains. For example, our Daily Peel with 7 % glycolic acid and our Acne Serum with salicylic acid are for daily use. It is always important to follow the product’s directions for use. You should also listen to your skin and adjust your use according to how it reacts to the product. It is always a good idea to start slowly on a small area and take breaks if your skin needs them.
2. What should I not mix acids with? AHA and BHA acids exfoliate the skin and cleanse clogged pores, which can make your skin more sensitive to other influences. You should therefore be careful about combining acids with other strong ingredients in your skincare, such as retinol, vitamin C and alcohol-based products.
3. How do I best care for my skin? When you use acids in your skincare, you need to protect it especially well against external influences such as sunlight, pollution and other environmental factors. Use good face creams and sunscreen with high SPF to protect your sensitive skin from sun damage and irritation.

When can you see the effects of AHA, BHA and PHA in skincare?

Using acids in skincare has many benefits, and some appear almost immediately. Skin quickly gains a lovely glow, skincare products penetrate better and makeup applies more smoothly. 

After a few weeks of continuous use of products with acids, skin becomes more even, and irregularities such as blemishes, pigmentation spots, age spots, strawberry skin and pores become less visible. AHA and PHA work on the skin’s surface to renew and add moisture, while BHA cleanses deeper in the pores and balances the skin’s natural oils. 

After about a month, fine lines will also be reduced and skin will feel firmer and tighter. This effect is due to the acids promoting cell renewal and removing dead skin cells, giving skin a renewed glow and a fresher appearance.

See, for example, our Peeling Mask, with AHA and PHA acids, or our AHA+BHA Mask, which is our most active peeling treatment and gives its first results in just two minutes.

How do I use AHA, BHA and PHA in my skincare?

Your skincare products with AHA, BHA and PHA acids should be applied to clean skin, so start by using a face cleanser to remove dirt and any makeup.

Next, apply your product with acids - it is typically serums, toners and masks that contain AHA, BHA and PHA acids. Serums and toners should not be rinsed off but left on the skin, while peeling masks should be removed according to the instructions, which can vary from mask to mask.

Our Peeling Mask can be left on for 4-12 minutes, depending on how accustomed you are to using it, while AHA+BHA Mask should only be left on for 2 minutes. Whichever product with acids you use, it is important to finish with a good face cream or face mask. Especially after a peeling mask, when skin needs extra moisture because of the effective exfoliation.

Read also: How to give your skin the most moisture and care

AHA, BHA and PHA for the body: Smooth and even skin

AHA, BHA and PHA acids can also make a difference in body care, for example for dry skin, dandruff and darker areas on elbows and knees, which are often caused by a build-up of dead skin cells that makes skin rough and uneven in colour. Here, the exfoliating effect of the acids can help remove dead skin cells and promote a more even tone.

The scalp can also benefit from acids – especially if you experience dryness or dandruff. Here, the acids help loosen and remove dry skin flakes, leaving the scalp cleaner and more balanced.

For the body, you can use our AHA Body Repair, a body lotion with glycolic acid that softens and smooths the skin. If you experience concerns such as a dry scalp, dark spots or uneven skin texture, you can also use Daily Peel with 7 % glycolic acid – a liquid formula that can easily be applied to specific areas or the scalp. Both products help give skin a smoother, more even and well-cared-for appearance.

Can pregnant women use products with AHA, BHA and PHA acids?

Choosing which skincare to use during pregnancy is always a personal decision, but we generally recommend choosing allergy-certified products.

Both our Daily Peel 7% and Peeling Mask contain AHA acids, and both can be used during pregnancy. You can also use Peeling Mask while breastfeeding. Your skin may react differently during this time, so first test the product on a small area of skin, for example by the jaw, and see how your skin reacts. If in doubt, ask your midwife or doctor.

Our AHA+BHA Mask also contains the BHA acid salicylic acid, and we advise against using the mask while pregnant or breastfeeding. Read more in our guide to pregnancy and skincare.

Active skincare products from ECOOKING

At ECOOKING, we develop skincare products according to this formula: Effectiveness first and foremost, followed by as much natural and organic content as possible. This means we place great emphasis on effective formulas with active and well-documented ingredients. 

We have organised our products by skin type and needs, so you can look for the products that can support your skin’s specific needs. This is how we take the best possible care of you and your skin. 

Shop by skin type here