Why apply glycolic acid to the underarms?

With increasing interest and discussion on social media and the Internet, the potential benefits of glycolic acid for underarm care have come into focus. While specific scientific studies directly evaluating its full range of benefits for the underarm area have yet to be carried out, several products featuring glycolic acid are already available on the market. These formulations typically contain glycolic acid at low concentrations (below 10%), with the aim of safely brightening and improving the appearance of darker patches of skin beneath the arms.

This hyperpigmentation in the underarm area is caused by melanin build-up and represents a source of self-consciousness for many women. Glycolic acid acts by accelerating the turnover of the skin’s outermost layer, promoting the shedding of pigmented cells and thereby reducing melanin accumulation. It achieves this via a process known as chemical exfoliation, in which it weakens the bonds between dead skin cells, facilitating their removal and revealing fresher, less pigmented skin beneath. Therefore, by applying glycolic acid to the underarm area, the hyperpigmentation in the underarm area can be gradually lightened and skin tone can be evened out.

However, once we take into account all the fascinating properties of glycolic acid, we cannot help but wonder whether there might be additional benefits? If you are experiencing irritation from daily shaving that leaves your underarms rough and bumpy, glycolic acid is an excellent exfoliant. It penetrates deeply into the skin to shed dead cells, clearing away debris that causes blocked pores and uneven texture. This penetration is enabled by its small molecular size, which allows it to reach deeper skin layers than other AHAs. It further penetrates to remove dead cells, eliminating the debris responsible for blocked pores and coarse texture. The result is fewer ingrown hairs and smoother skin.

The ongoing debate surrounding traditional deodorants and antiperspirants often centres on their ingredients, such as aluminium compounds and parabens, which some contend may pose potential health risks. What if glycolic acid-based solutions could replace them? Glycolic acid’s antibacterial properties do not only derive from its ability to exfoliate the top layer of the skin, removing bacteria, but also from its ability to reduce the skin's pH. This establishes an acidic environment that compromises the cell walls of alkaline-preferring bacteria, effectively diminishing their growth and presence, which aids in controlling body odour.

Beyond this, glycolic acid enhances the overall health of your underarm skin. It enhances hydration, supports barrier function, and optimises the skin’s ability to absorb other beneficial ingredients from your skin-care products. The acid’s capacity to hydrate derives from its water-soluble nature, drawing water molecules in and helping to keep the skin moist and resilient.

Incorporating glycolic acid into your underarm care is straightforward but necessitates meticulous attention to detail to ensure comfort and efficacy:

• Selecting Your Product: Seek out formulations specifically engineered for the underarm region, with glycolic acid concentrations appropriate for sensitive skin—typically around 8–10%.

• Application Tips: To begin, apply the product once or twice a week to clean, dry skin. As your skin acclimatises, you may increase the frequency, monitoring how your skin responds to find the perfect balance. With regard to precautions for use, you should avoid applying glycolic acid to freshly shaved or depilated skin.

• Protect Your Skin: Glycolic acid can render your skin more susceptible to solar radiation. Should your underarms be exposed, it is essential to apply a broad-spectrum sunscreen to safeguard your newly sensitised skin.

As social media and online discussions fuel interest in the use of glycolic acid for armpits, a variety of specialised products have emerged to cater to this growing demand. Although direct scientific studies specifically examining the efficacy of glycolic acid for armpit application are limited, the recognised benefits from its use on other parts of the body offer encouraging indications. These preliminary insights suggest that glycolic acid could potentially enhance armpit skincare by addressing issues such as discolouration, roughness and even body odour; however, this has yet to be confirmed by forthcoming clinical studies.

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