AHA and BHA play an important role in many skin care products and are superstar ingredients for exfoliation. You’ll see them on the labels for scrubs, peels, masks, moisturizers, toners, and cleansers.

They share many similarities, starting with the ‘HA’, which stands for hydroxy acids. It might sound a bit intense, but the ‘acid’ part is what gives AHAs and BHAs their exfoliation superpowers, as it works to cleanse dead cells and refresh your skin.

However, AHAs and BHAs do operate differently. Each can help you tackle a specific skin concern and achieve results that can improve your skin (and make you feel amazing). 

Here we delve a little deeper into the details, so you can decide which AHA and BHA products are right for you. Remember – it’s not a question of AHA versus BHA, but rather which one to use for a specific purpose.

A quick word about exfoliation

Exfoliation is the main purpose of AHA and BHA in skincare products – but why is exfoliation so important in the first place?

Your skin is constantly shedding dead cells, which build up on the surface. Over time, this can result in clogged pores, uneven coloring, as well as make lines, wrinkles, and blemishes more prominent.

Exfoliating works to clear out these dead cells, which brightens your tone, promotes healthier skin, and encourages collagen production.

There are lots of ways to incorporate exfoliation in your skincare routine, from everyday cleansers to bi-monthly face peels. AHA and BHA are ingredients that play a big role in these methods.

What is AHA?

AHA stands for alpha hydroxy acid. There are a few different types of AHAs that are used in skincare products, which are made from plant and animal acids. If you notice any of the following ingredients listed on the label, your product contains AHA:

• Glyocolic acid
• Lactic acid
• Citric acid
• Tartaric acid
• Malic acid

AHAs vary in strength: 15% AHA is the limit that products are allowed to contain, but most products don’t contain more than 10%. The stronger the AHA concentration, the higher the exfoliating power.

A great tool for exfoliation, AHAs are particularly popular for ageing skin and dry skin.

They are water-soluble, which means they operate at the surface of your skin and peel away the layer of dead cells and other particles that have built up. That’s why you’ll probably notice that your skin feels smoother after using a product containing AHAs.

As AHA tackles the outer layer of your skin, it’s important to wear sunscreen and UV protection after using AHA products.

What is BHA? 

BHA stands for beta hydroxy acid. There’s really only one main type of BHA used in skincare products: salicylic acid.

BHAs can be found in multiple strengths, typically ranging for 0.5% to 5%.

Exfoliation is the main purpose of BHAs, and they are great for cleansing skin and tackling blackheads and whiteheads – a popular recommendation for acne-prone skin and oily skin.

BHAs are oil-soluble, which means they can get to the oil beneath the skin and dry it out. This helps to unclog pores and clear away dead skin cells lingering in hair follicles. Some skincare professionals also point towards BHA products for treating rosacea-related redness.

Typically gentler in design, BHAs are often recommended for those who have sensitive skin or combination skin. As with any exfoliant, it’s extra-important to protect your skin with sunscreen after using BHA products.

Comparing AHA and BHA

Similarities

Both AHA and BHA:

• Exfoliate your skin by way of removing dead skin cells
• Help create a more even skin tone and texture
• Help improve appearance of large pores
• Unclog pores to help with acne prevention
• Make your skin more sensitive to UV rays – always apply sunscreen after using AHA or BHA products

Differences

Some key things that set AHA and BHAs apart are:

• There are multiple variants of AHA, but only one BHA
• AHA is typically recommended for age-related treatment (such as improving the appearance of lines and wrinkles) while BHA is typically recommended for sensitive and acne-prone skin
• AHA is water soluble and tends to act on the surface, while BHA is oil soluble and can get underneath the top layer of your skin.

Advice on using AHA products

AHA products provide amazing surface-level exfoliation and tend to be a great choice for dry or ageing skin. Within the AHA umbrella, there are a few different varieties:

• Glycolic acid: Provides lots of exfoliation and tackles the top layer of skin while stimulating collagen production. Note that it can be more irritating if you have sensitive skin.
• Lactic acid: Great for anti-aging improving skin tone.
• Tartaric: Typically recommended for improving color and tone, as it’s great at reducing skin discoloration affected by sun damage and acne.
• Citric acid: A good all-round exfoliator for evening out skin tone and texture.
• Malic acid: A more subtle AHA that’s typically used to support other ingredients in combination products.

There are many ways to integrate AHAs into your routine – how you do it and how often will depend on your skincare goals.

If you want to generally boost the tone of your skin, consider using a daily exfoliant containing AHA. Alternatively, if you’re looking for a one-off exfoliating boost, consider applying a skin peel treatment that contains AHA once or twice a month.

As with any skincare product, don’t go all in at first – try it sparingly (perhaps every other day or on just a small area) to see how your skin reacts.

Advice on using BHA products

BHA provides a gentler form of exfoliation that can penetrate beneath the surface level, which makes it a great option for oily skin, blocked pores, acne, and inflammation. As well as removing dead skin cells, it can unclog pores and follicles, actively tackling whiteheads and blackheads.

It also has antibacterial and anti-inflammatory qualities, meaning it can soothe irritation and help prevent future buildup and breakouts.

All of these qualities make BHA products a great daily choice for oily skin, acne-prone skin, and combination skin. As it tends to be less intense than AHA, it can also be a good option for those with sensitive skin conditions. 

Consider incorporating BHA into your daily routine, by way of a cleanser or scrub. You can also apply leave-on BHA exfoliator, for a quick, on-the-go solution.

FAQs about AHA and BHA

Below, we’ve answered common questions about AHA and BHA use, to help you work out how they should fit into your skincare routine. 

It’s important to note that everyone’s skin is different, and so you should consult a skincare professional whenever possible to get customized advice tailored to your skin type.

Can I use both AHA and BHA products?

Yes – in fact, it’s often recommended to find a balance between AHA and BHA, in order to cover all bases for your skin. However, it’s really important to get the balance right – both are strong exfoliators, and overuse could damage your skin.

 Consider using a BHA cleanser every day and integrating an AHA mask or scrub every few weeks. Depending on the product, you could also use one in the morning and one at night, stick to alternating days, or apply them at the same regularity to different parts of your skin.

Whatever routine you decide to test out, always use new products gradually at first to make sure they’re compatible with your skin. 

How often should I use AHAs and BHAs?

It depends on the product, your skin type, and what you’re trying to achieve. Mild AHAs are suitable for everyday use, while strong AHAs should be limited to a few times a week, or less.

Okay, so then what are PHAs?

PHA stands for polyhydroxy acids. They work in a similar way as AHAs, except don’t penetrate as deeply. This makes them a good option for people with sensitive skin.

Can you use AHA and BHA with retinol?

Yes – it’s a common myth that AHA and BHA will negate the effects of retinol, but we haven’t seen any actual trustworthy studies that back this up. However, there is some concern about possible irritation that can arise when using both of these products in conjunction.

When mixing AHA and BHA into your retinol regime, do it slowly to monitor your skin’s reaction. Consider using one in the morning and one at night and paying close attention to the results.

Is it okay to use AHA every day?

Yes, depending on your skin type and the strength of the AHA product you’re using.

High concentration AHA products (10% or more) should be used in moderation, to avoid irritation. Lower concentration products can be used more frequently, as long as your skin doesn’t object.

Which acid is best for acne?

BHA tends to be recommended as a daily option for acne-prone skin, as it can penetrate beneath the surface layer and work against oil that’s collected in your pores.

If you’re looking for a total refresh, AHA scrubs are an effective exfoliating treatment. 

What should I not mix with AHA and BHA?

When incorporating products into your routine and deciding which ones to avoid, think about the main function they’re designed to perform. AHA and BHA are both exfoliants, and so you should avoid mixing in other heavy-duty exfoliating products.

Avoid using Vitamin C with AHA, as AHA can disrupt Vitamin C’s pH balance and undermine its effectiveness, as well as risk irritation.

When used in conjunction with your skin type and needs, AHA and BHA can be amazing additions to your routine. If you want to get further into the acid conversation, check out our post on HA (hyaluronic acid) or check out our tips on anti-aging exfoliation.