If it's not already a staple in your evening skincare routine, retinol is a vitamin A derivative, which, according to Dr Anjali Mahto, consultant dermatologist at Skin 55, prompts the skin’s outer layer to grow at a quicker rate, stimulating collagen production, and exfoliating the top layers of skin cells.
Similarly, alpha hydroxy acids (AHAs) like lactic, azelaic and glycolic acid work to exfoliate the skin's surface, unclogging pores and uncovering newer, brighter skin cells, while beta hydroxy acids, such as salicylic acid, penetrate the pore, preventing the build-up of oil and dead skin. Together, they sound like the ultimate weapon against common skin gripes like acne, hyperpigmentation, fine lines and wrinkles. In fact, skin experts often encourage us to incorporate them into our routines and beauty brands are formulating more and more of their products with the wonder ingredients. The only thing is, both retinol and acids have a reputation for being harsh on skin, so is it actually safe to use the two together, or should we choose just one?
"I definitely wouldn’t apply an alpha hydroxy acid, like glycolic acid, and retinol at the same time," explains London-based consultant dermatologist, Dr Justine Kluk. "The reason is because both of these carry a high risk of irritant contact dermatitis, characterised by redness, peeling and sensitivity. The chances of skin sensitivity increase exponentially if both are used in the same skincare routine, let alone one after the other."
"Both retinol and AHAs chemically exfoliate the skin, brighten the complexion, reduce pigmentation and prevent fine lines," Dr Kluk continues. "There is a stronger evidence base for retinol and other vitamin A derivatives (such as retinoids), so this would be my preference over AHAs for slowing the signs of ageing, unless it can’t be used or hasn’t been tolerated for one reason or another. Overall, it’s far better to use one active ingredient regularly – either retinol or acids – and to tolerate it well, than trying to use both and ending up with an adverse reaction."
This is something Dr Colette Haydon, founder of Lixir Skin, seconds. "If you are leaving the product on the skin overnight it’s better to only use one active at a time to properly benefit from your skincare regime," she told R29. But if you do want to incorporate the two into your routine, this is how to do it safely. "I would recommend using a retinol every evening for four weeks, letting the skin rest for a few days and then switching to an acid like the Lixir Skin BHA/AHA 10% Night Switch, £20, for three weeks. If you use one active ingredient for too long it can have a plateau effect so keep your skin interested by switching it up." Her top tip? "You could also use acids in a mask form (R29 recommends Tata Harper's Clarifying Mask, £59) while using a retinol night treatment as the acid isn’t being left on the skin. However, I would advise never to use the two together as a leave-on nighttime regime."
Dr Mahto elaborates: "Washing with an AHA based cleanser (R29 rates Goldfaden MD's Detox Clafirying Wash, £32) then using retinol is usually safe for oily, blemish prone skin, but is not suitable for dry or sensitive skin. AHA allows better penetration of retinol and can be safely used as part of an anti-acne or anti-ageing routine with guidance and gradual build-up. I usually build my patients up to eventually tolerate an AHA cleanser plus retinol or retinoid for anti-aging and acne purposes - I use Medik8's Crystal Retinal 6, £59. A routine like this requires time and guidance under an experience dermatologist for best results."
And if you're using one or the other, or even both alternately, remember that they are likely to make your skin more sensitive to UV, so always wear the correct level of sun protection during the day.
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