Everything You Need to Know About Choosing an AHA Exfoliant

We like to be kind to the delicate skin on our faces — there's a reason that so many self-care routines focus on pampering your complexion. So, if applying acid to your face sounds a little intimidating, who could blame you for being apprehensive?

Don't let the name scare you. Acids, like the ever-popular alpha hydroxy acids (AHAs), offer some incredible skincare benefits!

Primarily known for their exfoliating powers, AHAs break down the intercellular "glue" that holds dead skin cells together. Once these bonds dissolve, the debris falls away — allowing newer skin to rise to the surface. An AHA exfoliant has the power to unclog pores, zap zits, fade hyperpigmentation and soften fine lines all at the same time.

With sources ranging from sugar cane to citrus, these water-soluble acids are seriously versatile. Depending on the one you choose, you might see added benefits ranging from a boost in collagen to more hydrated skin.

So, what are the different kinds of AHAs? Where do they come from? And which one should you use? You can end your search here — we've gathered everything you need to know about the most common types of AHA exfoliants.

Glycolic acid has the smallest molecules of all the alpha hydroxy acids, allowing it to sneak past other particles and penetrate deeper into the skin. The deeper it goes, the more dramatic the results are — it not only whisks away dead cells but tackles sun damage, hyperpigmentation, fine lines and wrinkles at their source.

As an added bonus, this sugar cane-derived acid is a humectant, which attracts water to keep skin plump and hydrated. It's without a doubt the most hardworking of all AHAs. However, this effectiveness comes with a slight catch: Glycolic acid is very powerful, and it can irritate skin that's not used to it! Start slow with a product that contains less than 5 percent of the acid and work your way up to stronger formulas in the 8-10 percent range.

Lactic acid is a great introduction to AHAs. Derived from sour milk, it has larger molecules than glycolic acid. Lactic acid is an effective multitasker that can do everything glycolic acid does — just a bit more gently, as the molecules take longer to penetrate the skin.

To properly harness the hydrating properties of lactic acid, look for a concentration of 2 percent and above. For exfoliation, you'll want concentrations of 5-10 percent. To help thicken the epidermis and boost collagen production, look for an even more concentrated product (about 12 percent).

Slated to be the next big skincare ingredient, mandelic acid has larger molecules, making it a great maintenance-level AHA. It works more slowly, so it's good for skin that's extremely sensitive but could still benefit from having a weapon against issues like hyperpigmentation, sun damage and fine lines. Extracted from bitter almonds, mandelic acid's strong antimicrobial properties also guard skin from acne!

Malic acid is another larger-molecule AHA, this one derived from apples. It does have some exfoliating powers, but not enough to be effective as a stand-alone ingredient. Instead, at concentrations of up to 2 percent, malic acid makes a great supporting player in combination products, where it helps glycolic and lactic acids to work more effectively.

The molecule size of tartaric acid is almost double that of glycolic acid. As a result, it penetrates skin too slowly to be truly effective on its own. Where this AHA really shines is as a pH adjuster! Tartaric acid naturally occurs in grapes, bananas and tamarinds, so it contains beneficial antioxidant properties and primes stronger acids to work their magic.

True to its name, this AHA comes from citrus fruits like oranges and lemons. Although it does act as an AHA exfoliant in concentrations of 10 percent and higher, its low 2.2 pH can increase the skin's sensitivity. Citric acid is prized for its antioxidant and antibacterial properties, often finding its way into acne formulations and sunscreens in lower concentrations. Like tartaric acid, it also makes a great pH adjuster, keeping formulas within the acid-alkaline ratio they need to be effective and nonirritating.