From how it works to how to incorporate it into your routine, read on for everything you need to know about this “holy grail” acid.

What Is Glycolic Acid?

Simply put, glycolic acid is a colorless, odorless, highly water-soluble molecule (or, more specifically, alpha-hydroxy acid) derived from sugarcane. “Of the alpha hydroxy acids, glycolic acid is the smallest molecule with the least complex chemical structure, which allows it to more easily penetrate the outer layers of the skin and get to work,” explains Jeffrey Fromowitz, M.D., a board-certified dermatologist in Boca Raton, Florida.

What Does Glycolic Acid Do?

According to Dr. Fromowitz, glycolic acid works by aiding the dull and outer layers of the skin in exfoliation, making for brighter, healthier, and more hydrated skin underneath. “It dissolves the connections between the cells that make up the stratum corneum (the skin’s outer layer) and increases skin cell turnover,” he explains. As a product, glycolic acid can improve acne and help correct pigmentation problems. Dr. Fromowitz points out there is also evidence that suggests regular use of glycolic acid can help improve fine lines and wrinkles. “As it penetrates into the skin’s surface, it activates fibroblasts, which are the cells in the skin that produce collagen,” he explains. Translation: It’s an anti-aging powerhouse.

How Often Should You Use Glycolic Acid?

As for how to incorporate glycolic acid into your routine, Dr. Fromowitz suggests starting with a wash to reap the benefits, while limiting contact exposure. “Those with sensitive skin should start slowly, perhaps using a wash only a couple days a week and building up from there,” he adds, noting that side effects can include redness, skin sensitivity, dryness, and itchiness. After a few weeks without irritation, you should be set to increase your frequency. “If daily use is tolerated well and you’d like to address other skin concerns, you can potentially add in a topical leave-on product that has glycolic acid as an ingredient.”

Can You Use Glycolic Acid With Retinol?

As with most acids, Dr. Fromowitz cautions this is one area where it’s not wise to play chemist. “You want to be careful not to combine AHA products with other acids or exfoliating products such as retinol, benzoyl peroxide, or salicylic acid. You should take care if you are treating acne with prescription products that contain Retin A.” If you still have questions, it’s best to seek advice from a trained professional (such as a dermatologist) who can assess your routine and prescribe the best products and formulas for you.

What Should You Look for in Glycolic Acid Products?

Glycolic acid can be found in a range of products and formulas, from washes to serums to creams. “You want to look for well-formulated products from well-known brands,” advises Dr. Fromowitz. “They will contain different percentages of active ingredients. Opt for lower concentrations in the beginning to allow the skin to adjust and minimize irritation. Lower concentrations also tend to be better for daily use.” Dr. Fromowitz says you should keep your skin type and condition in mind. “If your skin is on the oily side, you might want to start with a serum. if your skin is on the dry side, a cream formula may be the best option.” As for product picks, Dr. Fromowitz has become a fan of Glytone for well-formulated, affordable glycolic acid products. “The Skinmedica HA5 line also has good science behind the ingredients so the results are predictable and dependable,” he recommends. Curious to give glycolic acid a try? Shop our favorite glycolic acid serums, toners, peels, and face washes below.

Best Glycolic Acid Products for Skin