AHA vs. BHA: Differences, Benefits, Uses and Alternatives

• AHAs and BHAs are both varieties of hydroxy acids found in a variety of exfoliating products, including toners, creams, peels and masks.
• The chief purpose of both AHAs and BHAs is to remove dead skin cells stuck to the surface of the skin.
• Neither AHAs or BHAs are superior to the other. They simply have different uses dependent on your skin type and condition.

Chemical exfoliants most often come in the form of alpha hydroxy acids (AHAs), and beta hydroxy acids (BHAs), with some offering a combination of both. 

The product that will most benefit your skin depends on your specific skin type as well as any dermatological conditions you may have.

What Are AHAs and BHAs?

AHAs and BHAs are both highly effective chemical exfoliants that work to unclog your pores, “ungluing” dead skin cells that have built up on the surface of your skin. 

Uses

When used regularly and correctly, a well-selected hydroxy acid exfoliation product can address a wide range of skin concerns and conditions. 

AHAs are primarily used to treat:

• Skin that is dull or rough
• Skin with dark spots or sun spots, such as hyperpigmentation
• Skin with superficial atrophic acne scars
• Signs of aging such as wrinkles and dryness
• Acne, although studies are inconclusive

BHAs are primarily used to treat:

• Acne and acne-prone skin
• OIly skin (helps to keep it under control)
• Blackheads and sebaceous filaments (tiny collections of oil and dead skin cells around a hair follicle)

Is one better than the other?

Neither AHA or BHA is superior to the other. Rather, they simply have different uses which are well-suited to different skin care needs. 

The exfoliating product you choose will be a reflection of your skin type and condition far more than the quality of one hydroxy acid over the other.

Similarities

AHAs and BHAs both work to unstick the bonds keeping dull, dead skin glued to the surface of your skin for an overall smoother and younger looking appearance. 

AHAs and BHAs share a number of other benefits as well:

• They reduce the appearance of fine lines and wrinkles
• They make skin look and feel firmer by increasing collagen
• They help skin retain moisture and stay hydrated
• They improve the look of dull, uneven skin 
• They smooth rough, bumpy skin by sloughing off the dead cells

In spite of the many skin care benefits that AHAs and BHAs share, each also has different properties that make one a stronger choice than the other for specific skin types and concerns.

Differences between AHAs and BHAs 

While AHAs hasten the skin’s natural shedding process, BHAs penetrate deeper into the skin.

If you have surface-level skin concerns like hyperpigmentation, or dry skin, AHAs may be helpful, as they are water soluble and help improve the skin’s moisture content. 

Oil soluble BHAs are best for deeper skin concerns like acne or blackheads, as they can travel deeper into the pores to remove dead skin cells and excess oil. They also have anti-inflammatory and antibacterial properties. 

Should You Use AHAs or BHAs?

Gentle, hydrating AHAs are most well-suited to dry or normal skin types. Although AHAs are often touted as safe for all skin types, if you have extremely dry and sensitive skin, you should initiate use slowly and gradually work up to a daily routine in order to avoid irritation. 

Because BHAs go deep into your pores to dry out excess oils and dead skin cells, they are most suitable for normal to oily or combination skin. Lower concentrations can be used to help calm sensitive or inflamed skin. 

Regardless of which product you select, always be sure to perform a spot test before applying it to your skin.

AHA Candidates

The effects and uses of AHAs can vary slightly between acid levels. It’s typically best to choose an AHA with a maximum acid concentration of 10-15%.

Apply any new products every other day until your skin gets used to it, and then increase to daily use if needed. This will help to reduce the risk of irritation. 

AHAs make your skin more sensitive to the sun, so be sure to wear sunscreen to prevent burns, age spots, and increased skin cancer risks.

For best results, choose an AHA type that best suits your skin type(s) or condition(s):

	Skin types	Skin conditions
Glycolic	Normal, dry	Dryness, dark spots, wrinkles
Lactic	Dry	Dryness, dark spots, wrinkles
Tartaric	Acne	Sun damage
Citric	Normal, oily	Rough skin, sun damage
Malic (combination ingredient)	Normal, oily, dry	Wrinkles
Mandelic (combination ingredient)	Normal, oily	Rough skin, clogged pores, dullness

BHA Candidates

Salicylic acid is the most common BHA, and appropriate concentrations range between 0.5-5% depending on the product. 

Like AHAs, BHAs are also designed for daily use, but you may need to start by applying them just 2-3 per week at first until your skin grows more accustomed. 

Although BHAs don’t make your skin as sensitive to the sun as do AHAs, you should still wear sunscreen everyday to prevent further sun damage.

For best results, choose a BHA type that best suits your skin type(s) or condition(s):

	Skin types	Skin conditions
Salicylic acid	Acne	Redness, inflammation, fine lines
Citric acid	Oily	Excess oil, clogged pores, dark spots

Can you combine AHAs and BHAs?

AHAs and BHAs can produce fuller-looking skin when used in combination. This may be due to stimulated collagen production, which can make both the dermis and the epidermis visibly plumper and firmer.

For this reason, many occasional-use products contain both hydroxy acids. However, they may not be suited to your skin type, particularly if you have combination skin. In such a case, it may be wiser to use separate AHA and BHA products.

Nevertheless, it’s important never to layer AHA and BHA products on top of each other. They are both powerful exfoliators, so applying them simultaneously can cause dryness and irritation. 

You might try using AHAs and BHAs on alternating days, or only on certain parts of your face. For example, you can apply an AHA to dryer areas and a BHA to oily areas if you have combination skin.

Alternatives to AHA and BHA

Both AHA and BHA can be irritating to certain skin types. It’s recommended that people with darker skin, sensitive skin, or redness exercise caution when using either product.

Although allergies to AHAs are very rare, allergies to salicylic acid are slightly more common.

Those with sensitivities to AHAs or BHAs may experience irritation, redness, or flaky skin after using either type of hydroxy acid.

Luckily, there exists a variety of alternatives to both AHAs and BHAs if you find you do not tolerate hydroxy acids well.

Retinol

Made from vitamin A, retinol is commonly added to skin care creams. It boosts the amount of collagen in your skin, plumping it up, and reducing fine lines and wrinkles. It also improves skin tone and reduces uneven patches. It poses a low risk of irritation and may be more effective than glycolic acid.

PHAs

A new generation of AHAs, polyhydroxy acids (PHAs) provide have a similar effect to AHAs but with less irritation. are an attractive option for those with dry or sensitive skin as they are humectants, meaning they attract water and are ultimately moisturizing. because it’s a gentler ingredient, those with dry, itchy skin, eczema, or rosacea may benefit.

LHAs

Lipohydroxy acids (LHAs) are a salicylic acid derivative that replenishes skin while helping to buff away calluses and rough patches and inhibiting acne. Its unique structure is more tolerable than salicylic acid for some skin types.

Benzoyl peroxide

Benzoyl peroxide is a great alternative to salicylic acid because it fights both bacterial overgrowth and clogged pores. Since it can be drying however, start off with a lower concentration (around 2.5%) and work your way up. Benzoyl peroxide is generally effective at preventing breakouts.

Zinc

Particularly if you have an oily skin type, adding zinc to your skin care routine may help to clear up and balance out any buildup of oil. Topical 5% zinc sulphate has been shown effective for treating mild to moderate acne.

Takeaway

AHAs and BHAs are both powerful chemical exfoliants which offer a number of similar skin care benefits. However, each ingredient can be used to achieve different skin care goals or treat specific skin care conditions. 

AHAs and BHAs are also sold in combined formulas to boost collagen growth and firm up skin. 

If you are sensitive to hydroxy acids, there are a number of effective alternatives suited to different skin types and conditions which help to unclog pores, lift away dead skin, and treat a range of other skin concerns.