Which Should You Choose: AHA or BHA?

Let’s talk AHA’s and BHA’s. If you didn’t already know, there are two different types of skin exfoliants: Mechanical (or Physical) and Chemical. A Mechanical exfoliant would be something that typically has some grit or texture to it and will manually scrub (or sloth) off any dead skin cells sitting on the surface of your skin. Chemical exfoliants also help to get rid of dead skin cells, but instead of scrubbing, they dissolve or “digest” them away. This makes Chemical exfoliation a better option for those who have sensitive or reactive skin because they an be less stimulating.

AHA’s and BHA’s are also known as acid (or enzyme) exfoliants, because they’re exactly that, acids. So what’s their deal?

AHA: Alpha-hydroxy-acid derived from sugarcane, milk, or fruit.

“AHAs are water soluble molecules,” says Melanie Blum, Cosmetic Chemist on the Botnia Team. “They will mainly interact with the outer layer of your skin (the stratum corneum - which is about 20-30% water) to remove the dead skin cells... this will in turn reduce fine lines and wrinkles, hyperpigmentation and will result in a plumping effect.” There are six different types of AHA’s that can be found in skincare, but the most popular are Glycolic Acid and Lactid Acid. Glycolic Acid is the most common and is derived from sugarcane. It is the strongest of the AHA’s and is most famous for its ability to tackle pore congestion and release sticky sebum, but this also makes it the most irritating. Lactic Acid is derived from milk and is more gentle and less aggressive than Glycolic.

BHA: Beta-hydroxy-acid found in willow tree bark, wintergreen bark, and sweet birch bark.

“BHAs are oil soluble molecules,” says Melanie. “They will dig deeper into the skin because they can get into the sebaceous glands (which hold and excrete oil) in the dermis. This will very effectively clean pores. BHAs are excellent for acne prone skin— which is why salicylic acid is often used in acne treatments.” Salicylic Acid’s strength is comparable to Glycolic Acid, but it’s not nearly as irritating and also contains anti-inflammatory properties. Betaine Salicylate is a gentle alternative to Salicylic and is comparable in strength (although you’ll need a higher percentage, of course!). Salix Alba or Willow Bark Extract is a natural BHA that is extracted from plants and is able to convert into a more gentle version of Salicylic Acid.

Similarities:

  • Both AHA’s and BHA’s are effective at removing dead skin cells and smoothing out texture

  • Both help the skin look brighter and more even toned by reducing the thickness of the stratum corneum (top outer layer of skin)

  • They are both able to fade dark spots and pigmentation by helping to shed old, discolored skin

  • Both increase collagen in the skin which can then reduce intensity of fine lines and wrinkles

  • They are both natural humectants— meaning they help to attract water and retain moisture in the skin— which makes them great at deeply hydrating

  • Can help clear/prevent acne by getting rid of dead skin cells which can clog pores

Differences:

  • AHA’s dissolve in water, while BHA’s dissolve in oil, making them a better choice for those with oily skin

  • AHA’s require a higher percentage (at least 8%) to be effective, while BHA’s need as little as 0.5%

  • BHA’s are better at treating acne as they can go deeper into the skin and prevent new breakouts, while also slowing down oil production and loosening up blackheads

  • BHA’s help to “tighten” pores by keeping them clean. (“Large pores” are genetic but can also be effected by dirt and debris stretching them out)

  • BHA’s are more gentle and anti-inflammatory

  • AHA’s can make skin more sensitive to the sun

Things to remember:

  • You don’t need an AHA if you have a good BHA!

  • Both can be combined (and lots of products contain both, actually!)

  • Use BHA’s in the morning and AHA’s at night


There are a ton of skincare ingredients out there and it can be difficult to know which ones work best for your skin. Of course, a facial is always the easiest and most accurate way to figure out exactly what your skin is in need of, but for times when you can’t get into a spa, we’re here to help decode what some of these ingredients are and who they’re perfect for!

Warmly,

Team Toccare