Alpha or Beta? How to Choose between AHA and BHA Acids for Clear, Radiant Skin.

Posted on April 02, 2015 by Rachel Duran

Rachel DuranCosmetics containing acids are a great way to reduce wrinkles, clarify skin, and exfoliate. But with two major types of acid, which hydroxyl formula is right for your skin?

Alpha hydroxyl acid (AHA) is most often seen as salicylic acid. And beta hydroxyl acid (BHA) can be found in products with glycolic or lactic acid. 

Both are exfoliating champs, meaning they remove dead skin cells. That makes way for new skin cells to surface which reveals more radiance. But while acronyms of AHA and BHA make these compounds appear similar, their differences prove beneficial for very particular skin types and their corresponding concerns.

Before you start shopping, here are the facts about AHA vs BHA so you can decide which formula is best for you.

Alpha Hydroxy Acids

AHAs react with the upper layer of the epidermis, weakening the binding properties of the lipids that hold your dead skin cells together. When you apply AHA, this outer skin “dissolves” to reveal the underlying skin. Sounds gross, but it’s a good thing that jump starts turnover.

AHAs are great for dry, sun-damaged skin, helping reveal radiance by reducing the appearance of wrinkles, roughness, hyper pigmentation, and maybe even stimulating collagen and elastin.

While there are many variations, glycolic acid and lactic acid penetrate a little better than their peers. When picking a formula, keep in mind that AHAs must be absorbed into the skin to do their work—skip the cleansers that rinse off before they’re able to dig in. Side effects include skin irritation and increased sun sensitivity. Darker skinned folks may experience pigment changes.

Beta Hydroxy Acids

BHS are lipid soluble, meaning they dissolve in oil or fat. This distinction makes BHAs better at penetrating pores full of sebum and they’re less irritating than AHAs—great news for those with sensitive skin or acne.

This exfoliant sloughs off dead skins to make way for the new, helping reduce the appearance of wrinkles, roughness, and pigmentation issues. Since BHA is derived from aspirin, these products also boast anti-inflammatory, skin-soothing, and anti-irritant benefits.

There’s really only one kind of BHA found in skincare: salicylic acid.. BHA can work its magic in lower concentrations, meaning you should scoop up products that list salicylic acid at least midway through the ingredient list or contain between one and two percent.

BHAs also need to be absorbed in the skin to work—skip washes and go for toners, gels, and lotions that wont get washed off right away. Both acids make your skin more susceptible to sun damage and for some people, sensitivity can increase by as much as 50 percent. Ouch! Always use sunscreen.


  • Rachel Duran is an editor at Arithmetic
  • About Us: Arithmetic is a new skincare company focused on helping adults achieve clear, healthy skin

Posted in acid, acne, aha, alpha hydroxy, beta hydroxy, bha, clear skin, exoliation, glycolic, lactic, salicylic



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