Glycolic Acid

Commonly derived from sugar cane, glycolic acid is the smallest of the alpha hydroxy acids (AHA). This potent ingredient effectively loosens and releases dead and dehydrated cells, increasing the rate of exfoliation on the surface of the skin. This exfoliation promotes cellular turnover, which helps minimize the appearance of fine lines, uneven texture, and dull skin tone. The effectiveness of glycolic acid is determined by its free acid value - the active acid available to work on your skin.

To fully understand why glycolic acid is good for skin, it is important to understand skin’s natural exfoliation process. Every day skin sheds dull, dead skin cells to reveal newer, healthier cells underneath. On average, this natural exfoliation or cellular turnover occurs every 28 days in young adults. However, cellular turnover slows as skin ages, resulting in a buildup of dead skin cells that contribute to dull skin and uneven tone and texture.

Glycolic acid is an essential ingredient that helps slough away dead and dehydrated skin cells on the surface layer of the skin. Unlike abrasive mechanical exfoliants that can tear the skin and cause inflammation, glycolic acid efficiently dissolves the bonds that bind dead surface cells to the skin, providing a gentle, yet effective exfoliation. This accelerated cellular turnover rate promotes skin clarity and a more even skin tone and texture.

SkinCeuticals has long been committed to researching innovative and effective sunscreen products. At the same time, we have taken great care to ensure the environmental safety of its products in both salt and freshwater environments. Any ingredient called into question for any reason is taken seriously by our team of toxicologists, clinicians, and chemists, who continuously evaluate each and every ingredient we use.

Overusing any chemical or mechanical exfoliating agent can result in redness or irritation. However, in moderate concentrations, glycolic acid can be tolerated for daily use to help facilitate the skin’s natural exfoliation. When considering a glycolic acid treatment for your skincare regimen, it is important to identify the right concentration for your specific skin concern.

Concentrations of glycolic acid for skin under 4% provide low-level exfoliation and may be used once or twice daily depending on the potency and pH value of the formula. Sometimes glycolic acid may be added to acne formulas at lower levels to enhance skin cell turnover. If looking for an effective nighttime product that primarily targets visible signs of aging such as fine lines, dullness, and skin texture, a 4-10% concentration of glycolic acid is recommended. Any glycolic acid formulation featuring a concentration above 20% should be recommended and administered by a skincare professional. This includes chemical peels, which may require pre-conditioning and specific post-procedure care.

Due to the exfoliating nature of glycolic acid, always apply a broad spectrum sunscreen during the day when using these products.

Not all glycolic acid skincare products are created equal. The free acid value, determined by pH level and concentration, dictates how beneficial the glycolic acid treatment will be in increasing cell turnover. A glycolic acid concentration of 4-10% is ideal for nightly use but a lower pH is necessary to preserve the strength of the glycolic acid for optimal efficacy. Always look for the free acid value in a glycolic formula, not just the total concentration claimed. As pH levels increase, glycolic acid may become largely neutralized, decreasing the effective acid level and weakening its strength. The key is finding a formula featuring the right balance between glycolic acid concentration and pH levels.

A glycolic acid peel is a chemical peel formulated with glycolic acid as the primary exfoliant in the peel solution. Performed by a skincare professional, these treatments exfoliate and resurface the topmost layer of the skin to reveal new, healthy skin underneath. They are effective in increasing cell turnover, softening the look of fine lines and wrinkles, and improving skin tone and texture. During a glycolic acid peel, one or more layers of the solution are applied onto the skin for a predetermined amount of time based on concentration, skin type, and the patient’s reactivity to the treatment. Once the solution is left on for the desired amount of time, the formula is neutralized with a buffering solution or water.

Following a glycolic acid peel, a skincare professional will apply post-procedure care, which includes a high SPF broad spectrum sunscreen to help protect skin against damaging UVA/UVB rays. After any type of chemical peel, skin is more susceptible to damage from environmental aggressors. Therefore, it is key that sunscreen is applied daily and diligently. Your skincare professional may also recommend advanced homecare to help maintain and protect the results of your glycolic acid peel.

Learn more about chemicals peels >

Yes, it is recommended that a moisturizer is applied after using a formula containing glycolic acid. Applying a glycolic acid formula in the evening is recommended due to the drying effect exfoliants can have on the skin. An evening application will help to prevent damage from sun exposure.

Glycolic acid and vitamin C can be used together. The combination of these two ingredients works synergistically to rejuvenate the look of skin by removing the outer layer of dead skin cells, that results in the skin accelerating the production of new skin cells, resulting in a new layer of smooth skin. Always apply the formula containing glycolic acid before the formula with vitamin C.

It is recommended to apply sunscreen before going outdoors when using formulas containing glycolic acid. This ingredient exfoliates the top layer of skin, which increases sensitivity to UVA/UVB rays.

Formulas containing glycolic acid and retinol should not be used in the same application. If you plan to use formulas with both ingredients as a part of your skincare regimen, it is recommended that you apply the glycolic acid formula in the morning, then the retinol formula at night. Separating applications will help to reduce possible skin irritation. Check with your physician before usage.