In addition to exfoliation, high potency glycolic acid can have other benefits as well. Though not typically thought of as a collagen booster, glycolic acid can activate underlying cellular processes that accelerate collagen synthesis by fibroblasts, and modulate matrix degradation through keratinocyte released cytokines (Okano et al. 2003). This collagen building ability was found to increase with increasing concentrations of glycolic acid all while avoiding triggering inflammation when kept at a pH of 4 or higher (Narda et al. 2020). In sun-damaged skin, glycolic acid was found to increase hyaluronic acid content in the epidermis and dermis as well as increasing collagen synthesis and epidermal thickness (Bernstein et al. 2001). In other words, glycolic acid creams are a helpful adjunct to use along with other more powerful anti-aging ingredients such as retinoids to aid in the collagen building process.

Next, glycolic acid creams can maintain the acidic pH level of the skin by supporting the acid mantle which in turn has a wide range of benefits. The skin surface and stratum corneum have a naturally acidic pH between 4.1 and 5.8 and this acidity (also referred to as “acid mantle”) is essential for maintaining the health of the skin (Lukic et al. 2021). Enzymes that build ceramides and other lipids in the skin barrier function best at a pH below 5, while increased pH activates serine proteases that degrade the skin barrier (Hachem et al. 2010). An acidic skin pH is necessary for a functioning skin barrier, which keeps bad bacteria like P. acnes out and keeps moisture in. By supporting the acid mantle, hydroxy acid creams have been shown to kill P. acnes bacteria, and increase skin moisture and strengthen the skin barrier (Valle-Gonzalez et al. 2020, Hachem et al. 2010, Rawlings et al 1996). Along with its exfoliative properties, supporting the acid mantle is one way in which high potency glycolic acid creams treat mild acne even when used alone as a monotherapy (Abels et al. 2011).