Glycolic Acid (AHA): benefits and uses for the skin

Among exfoliating acids, glycolic acid is undoubtedly the best known. It’s found in a wide variety of skincare products, from scrubs to peels, and has a solid reputation for brightening and smoothing the skin. But what exactly does it do, and how can you use it safely?

Glycolic acid is the most powerful and most extensively studied of the fruit acids; it can refine the skin's texture, restore radiance, and even out the complexion. Here are its benefits and the best ways to use it.

Glycolic acid, the star of fruit acids

Glycolic acid belongs to the AHA (alpha-hydroxy acids) family, a group of naturally occurring exfoliating acids. It is extracted from sugarcane and is distinguished by one key characteristic: it has the smallest molecule in this family. This small size allows it to penetrate the stratum corneum more easily, making it the most powerful and best-documented of the AHAs.

To understand how fruit acids work in general, you can read our article on fruit acids (AHAs). Here, we’ll focus on the specific properties of glycolic acid.

The Benefits of Glycolic Acid

Glycolic acid works by removing dead skin cells that accumulate on the skin’s surface, triggering a cascade of visible benefits. It refines the skin's texture and smooths its surface, significantly reviving the radiance of a dull complexion, and helps even out the skin tone by reducing the appearance of spots caused by sun exposure or aging.

Its effects go beyond the surface. Scientific data indicate that regular use can improve the appearance of the epidermis and dermis and stimulate skin renewal, which explains its benefits for skin affected by photoaging. By unclogging the skin’s surface, it also helps keep pores clear and promotes better absorption of subsequent skincare products.

How do you use glycolic acid?

It all comes down to concentration. Research makes it clear: depending on its concentration, glycolic acid can be a beneficial ingredient or a source of irritation. At moderate concentrations and in a well-formulated product, it exfoliates effectively while remaining gentle; at high concentrations, such as in chemical peels, it becomes more intense and must be used with caution.

In practice, it’s typically used in the evening, a few times a week or every other night, depending on the product and your skin’s tolerance. There are two essential rules: introduce it gradually to allow your skin to adjust, and apply sunscreen the next morning, since glycolic acid increases your skin’s sensitivity to the sun. This daily sun protection is, in fact, the best-documented measure against UV-induced aging.

For which skin types?

Glycolic acid is suitable for most skin types and is particularly beneficial for dull, uneven, or rough complexions, as well as for skin prone to breakouts. Sensitive skin can also benefit from it, provided you choose a mild concentration and a formula designed to preserve the skin barrier. Combining glycolic acid with a soothing active ingredient like niacinamide—which strengthens the barrier by stimulating ceramide synthesis—is an excellent strategy in this regard.

Glycolic acid in the PERS Triple Exfoliant

The PERS Triple Exfoliant contains 5% glycolic acid and 5% fruit AHAs, delivering a triple exfoliation that combines chemical, enzymatic, and mechanical action. To maintain skin softness, the formula is enriched with 5% niacinamide, which strengthens the skin barrier and helps reduce sensitivity.

This treatment harnesses the power of glycolic acid (radiance, refined texture, even skin tone) in a formula designed to be gentle and suitable for all skin types, even sensitive skin. Use it in the evening, every other night, as an exfoliator or mask, followed by a moisturizer and PERS SPF 50+ sunscreen the next day.

Key Takeaways

Glycolic acid is the most powerful and most extensively studied of the fruit acids, thanks to its small molecule that effectively penetrates the skin. It refines skin texture, restores radiance, evens out skin tone, and supports skin renewal. Both its effectiveness and tolerability depend on its concentration: when used in the right dosage, introduced gradually, and combined with daily sun protection and active ingredients that soothe the skin barrier, it becomes a valuable ally for visibly smoother and more radiant skin.

Scientific Sources