What are AHAs and BHAs?
AHAs and BHAs are types of hydroxy acids. You can find both acids in a variety of:
The purpose of both AHAs and BHAs is to exfoliate the skin. Depending on the concentration, a related product may remove dead skin cells from the surface of the skin, or it may remove the whole outermost layer.
Still, neither type of hydroxy acid is “better” than the other. Both are highly effective methods of deep exfoliation. The differences lie in their uses.
Read on to learn more about these differences so you can determine whether your skin needs an AHA or BHA product.
Do they have any shared benefits?
AHAs and BHAs are both skin exfoliants.
They can each
- decrease inflammation, a key marker of acne, rosacea, and other skin concerns
- decrease the appearance of large pores and surface wrinkles
- even out your skin tone
- improve overall skin texture
- remove dead skin cells
- unclog pores to prevent acne
How are AHAs and BHAs different?
AHA stands for alpha hydroxy acid. BHA stands for beta hydroxy acid.
AHAs are water-soluble acids made from sugary fruits. They help peel away the surface of your skin so that new, more evenly pigmented skin cells may generate and take their place. After use, you’ll likely notice that your skin is smoother to the touch.
On the other hand, BHAs are oil-soluble. Unlike AHAs, BHAs can get deeper into the pores to remove dead skin cells and excess sebum.
Which acid should you choose?
AHAs are primarily used for:
- mild hyperpigmentation like age spots, melasma, and scars
- enlarged pores
- fine lines and surface wrinkles
- uneven skin tone
Although AHAs are often marketed as safe for all skin types, you’ll want to take care if you have extremely dry and sensitive skin. You may need to gradually work up to daily use to avoid irritating your skin.
BHAs, on the other hand, are primarily used for acne and sun damage. These products go deep into your hair follicles to dry out excess oils and dead skin cells to unclog your pores. Because of these effects, BHAs are most suitable for combination to oily skin. Lower concentrations may be used to help calm sensitive skin. You may also have more success with BHAs if you wanted to reduce rosacea-related redness.
PRO TIPIf you’re primarily looking for dry skin relief or anti-aging benefits, try an AHA. If you want to tackle acne, look to BHAs.
How to use AHAs
All AHAs yield significant exfoliation. Still, the effects and uses can slightly vary between types of acids. Your selected AHA should have a maximum concentration between 10 and 15 percent. Apply new products every other day until your skin gets used to them. This will also reduce the risk of side effects, such as irritation.
No matter which AHA you choose, the strong exfoliating effects make your skin more sensitive to the sun. Wear sunscreen every morning to prevent burns, age spots, and increased skin cancer risks.
Glycolic acid provides significant exfoliation. This makes it an all-around treatment for many skin concerns. And thanks to its antimicrobial properties, it may even help prevent acne breakouts.
Glycolic acid is found in a number of peels, as well as daily skin care products. Popular options include:
- Juice Beauty Green Apple Peel, full strength
- Exuviance Triple Microdermabrasion Face Polish
- DermaDoctor Wrinkle Revenge Cleanser
- Mario Badescu Glycolic Acid Toner
Lactic acid is another common AHA. Unlike other AHAs made from fruits, lactic acid is made from lactose in milk. It’s also known for its significant exfoliation and anti-aging effects.
Like glycolic acid, lactic acid is found in a variety of products, such as:
- Patchology Milk Peel FlashMasque
- Dermalogica Gentle Cream Exfoliant
- DermaDoctor Ain’t Misbehavin’ Toner
- Rodial Super Acids Sleep Serum
While not as widely known, tartaric is another type of AHA. It’s made from grape extracts, and may help alleviate signs of sun damage and acne.
Check out some of the following products from Juice Beauty containing tartaric acid:
As its name suggests, citric acid is made from citrus fruit extracts. Its main purpose is to neutralize the skin’s pH levels and to even out rough patches of skin. Citric acid makes a good serum or toner used before applying a moisturizer. It may even help work with sunscreen to provide maximum UV protection.
Consider the following additions to your daytime routine:
- Exuviance Age Reverse Day Repair SPF 30
- Philosophy Ultimate Miracle Worker SPF 30
- Exuviance Daily Resurfacing Peel CA10
- Resurrection Beauty Citric Acid Powder
Malic acid is a type of AHA-BHA crossover. It’s made from apple acids. Compared to other AHAs, malic acid isn’t as effective as a solo ingredient. However, you might find it makes other acids more effective.
This is why malic acid is common in combination AHA products, such as:
Mandelic acid contains larger molecules derived from almond extracts. It can be combined with other AHAs to increase exfoliation. Used alone, the acid may improve texture and pore size.
Check out some of the combination products containing mandelic acid:
- Exuviance Performance Peel AP25
- Exuviance Night Renewal HydraGel
- Vivant Skin Care Mandelic Acid 3-1 Wash
- Cellbone Mandelic Acid Peel
How to use BHAs
BHAs are also designed for daily use, but you may need to apply a few times per week at first until your skin gets accustomed to them. Although BHAs don’t make your skin as sensitive to the sun compared to AHAs, you should still wear sunscreen every single day. This will help prevent further sun damage.
Salicylic acid is the most common BHA. Concentrations can range between 0.5 and 5 percent, depending on the product at hand. It’s well-known as an acne treatment, but it can also help calm down general redness and inflammation.
Consider some of the following salicylic acid products to add to your routine:
- Uplifting Miracle Worker Cool-Lift and Firm Moisturizer
- Philosophy Clear Days Ahead Oil-Free Salicylic Acid Acne Treatment Cleanser
- Skyn Iceland Blemish Dots with Salicylic Acid
- Proactiv+ Blackhead Dissolving Gel
While primarily classified as an AHA, some formulations of citric acid are BHAs, too. Rather than even out your skin’s pH levels, this type of citric acid is primarily used to dry out excess sebum and clean out dead skin cells deep in your pores. One such product is Philosophy’s Purity Made Simple Pore Extractor.
How to combine AHA and BHA products
According to a 2009 review, AHAs and BHAs yield fuller skin when used together. This may be due to increased collagen production, which can make both the dermis and epidermis visibly plumper.
Because of this, many occasional-use products, such as Proactiv+ Mark Correcting Pads, contain both acids.
Still, you don’t want to layer AHAs and BHAs on top of one another. These are both exfoliators, so using both can cause dryness and irritation.
PRO TIPYou can alternate products by using one type in the morning and the other during your nighttime routine.
You could also use AHAs and BHAs on alternating days. This method works well if you’re using at-home chemical peels that contain AHA.
Another strategy is to use these acids on certain parts of your face only. For example, you can apply an AHA to dry areas and a BHA to oily areas if you have combination skin.
The bottom line
AHAs and BHAs share similar benefits. You can obtain some level of exfoliation from each one.
However, each ingredient can be used to achieve different skin care goals. If you’re looking for an all-inclusive anti-aging treatment, then an AHA may be the best fit. A BHA may better suited if you want to calm down inflammation and get rid of acne.
If you still aren’t sure which to choose, talk to your dermatologist. They can answer any questions you have and recommend specific ingredients or products to try.
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