If you look up ingredients for skincare products, then you've likely come across the terms AHA and BHA, especially when dealing with acne-prone skin. Both AHAs (alpha-hydroxy acids) and BHAs (beta-hydroxy acids) are chemical exfoliants that break up the bonds holding skin cells together. This bond-breaking facilitates the removal of dead skin cells that are sticking to the surface of the skin and clogging pores. So, what's the difference between these two acids, and how do you know when to use which?
What are AHAs?
Alpha-hydroxy acids are sometimes referred to as "fruit acids" since they are naturally occurring in different fruits. They can penetrate and exfoliate the top layers of skin to give skin a smoother, brighter, and more polished appearance. Glycolic acid and lactic acid are the most commonly used AHAs in skincare. Glycolic acid is the smallest of the AHAs, which allows it to penetrate the skin easily. It also brings hydration to the surface, which is why so many skincare products that address aging, scarring, and skin discoloration contain glycolic acid.
When to use AHA's
The more common AHAs like glycolic acid or lactic acid function at less acidic pH's and are therefore gentler on the skin. This less acidic pH makes them ideal for daily use (when used at lower concentrations) to keep the skin hydrated, bright, and glowing. AHAs exfoliate only the top layer of skin, and therefore, it will take a few months of consistent use to notice results when dealing with fine lines or discoloration.
What are BHAs?
Beta-hydroxy acids are very similar structurally to alpha-hydroxy acids but differ in the number of carbon atoms between the hydroxyl and carboxyl groups. The most common BHA is salicylic acid, which is an FDA-approved active for acne treatment products. Salicylic acid is oil-soluble and can penetrate pores to reach deeper layers of skin. It also calms inflammation and kills acne-causing bacteria, which makes it a great acne-fighting ingredient, and it's a staple in the Dermala SCANTILY Pad AM/PM Acne Treatment.
When to use BHAs?
If your goal is to reduce acne and unclog pores, then salicylic acid should be your go-to ingredient. It can dig deep into pores to exfoliate deeper layers of the skin and keep pores unclogged. It also has antibacterial and anti-inflammatory properties that are helpful with acne. Salicylic acid is also beneficial for addressing dark spots, but for some people, it can be slightly more irritating than AHAs for daily use. When you begin using salicylic acid, start by applying a small amount to affected areas followed by a hydrating moisturizer once a day. As your skin becomes used to the acid, you can increase the application to the recommended twice a day.
So, the next time you need a skincare product, look for products that contain AHAs or BHAs. A BHA, like salicylic acid, is better for acne-prone skin while AHAs, like glycolic acid, are more common for addressing skin dullness, anti-aging, and dark spots. Both AHAs and BHAs increase sun sensitivity so be sure to use a broad-spectrum SPF daily when using these exfoliants. We hope we helped to clarify the world of AHAs and BHAs for you and showed you how amazing they are! But remember, everything needs time to work, so be consistent with your products to see results!