Acids for skincare are more than a thing of beauty now! With cosmeceutical brands formulating lower concentrations, they are a lot more accessible and even safe for at-home skincare. “Acids have been used for centuries for beautification. History records show that ancient Egyptians used sour milk, which is enriched with lactic acid, to lighten their skin,” says Dr Uktra Namshum, Clinical Dermatologist and founder of Hana Aesthetics in Delhi.
Targeting concerns like hyperpigmentation, redness, acne scars and the appearance of lines and wrinkles, acids have become essential for many. An added advantage is the fact that brands are formulating them at affordable price points; which is why they have found their way into body care as well. Case in point – using acids on underarms!
TikTokers have been swiping their underarms with The Ordinary Glycolic Acid 7% Toning Solution for months. However, those who claim that using acids on underarms also has deodorising benefits have our undivided attention. AHAs as deodorants? We were certainly intrigued.
“It is relatively safe to use acids on underarms as long as it is used in lower concentrations, so that the skin barrier is not compromised which can lead to irritation of skin and pigment worsening if they are used too frequently or in high concentrations,” revealed Dr Deepthi Ravishankar, consultant dermatologist and cosmetologist at Skinologycentre in Bangalore. They work by weakening and dissolving the melanocytes (pigment cells) and dead skin cells that are responsible for the darkening and hyperpigmentation.
Applying acids to the underarms helps shed the topmost layer of skin and facilitate the layer beneath the surface faster. This, in turn, helps achieve an even-toned skin surface, improves skin texture and also helps boost collagen production. They also eliminate odour causing bacteria by lowering the pH of the skin, making them the unlikeliest of underarm heroes.
However, they won’t help in reducing sweating as you need an aluminium-based compound to actually block the sweat. Dr Uktra explains that glycolic acid, salicylic acid and lactic acid are some of the best acids to use for the underarms. Anything between 5 to 7 per cent is good to start with but the lower the concentration, the better it is for experimentation.
While there are a few acids that dermats believe are safe for the sensitive underarm area, it’s the glycolic acid that stands out for its efficacy. Dr Deepthi further explains that “Glycolic acid is a fast-acting and effective solution for uneven underarms. It is easily available over the counter as well as on online platforms in different concentrations and formulations such as creams, serums, and peels.”
Given that one needs to be cautious about using acids for skincare, how can they be good for pits? The armpit area is sensitive and since it’s summer, we can’t ignore excessive sweating and overheating which leads to dryness and irritation. And if the acids are used in a strong concentration without proper guidance, they can lead to burns or irritation and worsening of hyperpigmentation marks. It is recommended to speak to a dermatologist about including acids in your routine.
Safety Tips On Using Acids On Underarms
Some of the expert-recommended tips to keep in mind while using acid on the underarms are –
1. Keep the area moisturised – Acids and peeling solutions, even in smaller concentrations, can lead to dryness and itching. It is important to moisturise with unfragranced formulations that are rich in vitamin E and C, niacinamide and hyaluronic acid.
2. Do not use strong deodorants on your underarm while using acids and it can lead to inflammation, skin thickening, and darkening.
3. Do not use physical scrubs or loofahs on the underarms as that can overexfoltae them and lead to sensitivity.
4. Avoid dry shaving as it can cause irritation. One can either wet shave or undergo laser hair reduction which is considered to be the best as it reduces the need to shave or use hair removal creams.
5. If you’ve had an unpleasant experience with glycolic acid, you can opt for a cream formulation containing azelaic acid, kojic acid, vitamin C and arbutin to tackle skin darkening instead.
6. Use SPF on your underarms whenever you know that they will be exposed to the sun.
What is glycolic acid and how does it work?
"Derived from sugarcane, glycolic acid is a chemical exfoliator, also referred to as an alpha-hydroxy acid or AHA," says Dr. Ana Mansouri, aesthetic doctor and skin expert at Kat & Co. "Its small molecular size makes it powerful and enables penetration deep into the skin layers. It essentially works by breaking the bonds between dead skin cells, which helps to resurface the top layer of the skin." Used over time, glycolic acid can help fade pigmentation and improve rough skin texture.
Glycolic acid is great on paper, but there are potential side effects and drawbacks you need to know about before using it. The ingredient is best used at night at relatively low percentages once or twice weekly, after cleansing and before moisturizer. As it can make skin sensitive to sunlight, wearing SPF during the day is all the more important. It pays to be careful with how often you're using it, too. "Overuse can lead to over-exfoliation, which can break the skin barrier function and lead to irritation, dehydration, and breakouts," says Dr. Mansouri.
Is glycolic acid a good alternative to deodorant?
Judging by the countless TikTok videos, beauty enthusiasts are using glycolic acid as deodorant mainly because they're looking for natural alternatives and love the idea of a multipurpose product. Dr. Priya Verma, medical director at Nova Aesthetic Clinic, explains that glycolic acid is said to "lower the pH of the underarm, creating an inhospitable environment for odor-causing bacteria," which explains why many TikTokers are championing it for reducing body odor. However, Dr. Mansouri says that this is simply a theory, and it isn't actually proven to reduce odor. What's more, Dr. Verma says there is little evidence that glycolic acid reduces sweating. "In fact, water from sweat will neutralize glycolic acid, reducing any benefits of the acid application," she says.
In other words, any benefits of that nature are based on anecdotal evidence. One thing glycolic acid may help improve is underarm pigmentation. (Of course, body pigmentation is entirely normal, but some people may wish to get rid of it as a matter of choice.) "As glycolic acid exfoliates the skin, it promotes a more rapid cell turnover and reduces the thickening of the skin that leads to underarm hyperpigmentation," explains Dr. Verma. "Used correctly, it is effective in reducing unwanted hyperpigmentation." Dr. Mansouri adds that there are better options for this purpose in the underarm area.
Is using glycolic acid as deodorant safe?
Glycolic acid can cause irritation on facial skin, so it follows that it can do the same to underarm skin. "Armpit skin is already sensitive in nature due to constant friction and rubbing, as well as a moist and occluded environment," says Dr. Mansouri, who adds that shaving can cause further sensitivity. That slight tingle you feel when applying glycolic acid toner to your face could be pretty painful on just-shaven underarms.
Dr. Verma adds that glycolic acid facial toners would be completely unsuitable for use if you’re having a course of laser hair removal in the underarm area. "Glycolic acid isn’t suitable for all, and more sensitive skin types may see an adverse reaction. Overuse can also lead to over-exfoliation, which compromises the skin’s protective barrier," causing redness and flakiness, she explains. "In the hot and humid environment of the underarm, this would be very undesirable."
While glycolic acid is said to reduce hyperpigmentation when used correctly, if you're using it too often and in high concentrations, it can actually worsen hyperpigmentation due to irritation. "I would prefer to keep the AHA use to the face, as this is what your product will have been formulated and intended for," says Dr. Mansouri.
What happens if you use glycolic acid as deodorant?
I'm all about putting trends and hacks to the test, occasionally even when they're ill-advised, so I couldn't resist giving this a go. I decanted a little glycolic acid onto a cotton pad before swiping it underneath my arms. Even though I'd waited a couple of days after shaving to avoid the dreaded sting, my skin still tinged. The initial application felt a little sticky, and I can safely say it did nothing to prevent sweating throughout the day — in fact, that stickiness lasted all day, which put me in a bad mood. I decided to test its supposed odor-reducing properties by going on a long walk; unfortunately, it didn't hold up as well as I'd hoped. The smell wasn't as strong as I'd anticipated, but I still noticed it at the end of the day and I couldn't wait to jump in the shower.
I love using The Ordinary's glycolic acid toner on my face (it helps fade marks left behind by spots and smooths bumpy skin texture like no other) but I wouldn't recommend using glycolic acid under your arms — not when there are so many great deodorants out there. Dr. Mansouri seconds this. "I am not a fan of this trend at all and would definitely recommend sticking to tried and tested deodorants or antiperspirants with research behind their use," she says. "Skin care should be backed by science, not trends."
What is the best deodorant or antiperspirant?
Plenty of TikTok videos warn that aluminum in deodorant is "unsafe" to health, but Dr. Mansouri busts this myth. "In contrast to popular belief, there is no hard evidence to suggest that aluminum chloride is actually harmful," she says. Dr. Verma also says to remember that aluminum-free "natural" deodorants won’t prevent sweating, but will simply combat odor.
Having tried hundreds of deodorants on the market, for me nothing beats Mitchum Powder Fresh Anti-Perspirant Roll On. It doesn't let a single bead of sweat pass, nixes odor, and really does last all day. The Shower Fresh version is just as excellent and is available in an aerosol version if you prefer quick-drying sprays. If you like natural deodorant, you might enjoy Scully's Deodormint Spritz. The formula is an astringent so it wipes out odor-causing bacteria and makes underarms feel fresher for longer.
How can you get rid of underarm sweating?
Firstly, sweating is entirely natural, but Dr. Mansouri says that anyone who struggles with excessive sweating or odor should see a doctor or dermatologist, who will be able to prescribe treatments. "Botox is another temporary option for sweating, although costly and laborious," says Dr. Mansouri. "I’m a big fan of the miraDry treatment that actually reduces underarm sweat permanently — my patients end up not needing to even use deodorants after having had this."
The expert consensus is that glycolic acid should be reserved for use on the face rather than underarms. Sorry, TikTokers: This hack isn't worth the hype.
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