September 16th 2021
A guide to using exfoliating acids in your skincare routine
June 4th 2018 / 0 comment
From salicylic to lactic to glycolic and more- here’s an A-Z of exfoliating acids, how to use them and which to pick to suit your skin type
Acid. As skincare ingredients go, it sounds harsh, unforgiving and in theory a very.bad.idea. Until you consider that, actually, antioxidant powerhouse vitamin C is an acid, essential fatty acids give skin, joints and generally our body’s cells life, and that the much hailed skin-rejuvenating agent retinol is also itself an acid. Acids aren’t looking quite so aggro now, actually.
No doubt you will have heard talk of exfoliating acids in the context of skincare too- if you’re a regular reader, you’ll be au fait with an exfoliating toner and the overwhelming preference of derms, facialists and skincare experts for chemical exfoliants over physical ones. Basically, on the whole, dissolving dead skin cells by way of an exfoliating acid is regarded as kinder to skin them sloughing away crud with a gritty scrub.
That said, exfoliating acids aren’t to be sploshed about willy nilly- use the wrong one and you could provoke irritation, while overuse can up your chances of sensitivity and sun damage. Here’s how to fine tune your acid use for smoother, clearer, brighter skin, pick the best acid for you in the first place and what to look for on the label.
Why use an exfoliating acid?
Because there’s nothing better to gobble up those lacklustre dead skin cells according to the pros. Acid over elbow grease every time- consultant dermatologist Dr Justine Kluk explains just a few acidic advantages:
“The benefits of introducing an acid include loosening the ‘cement’ between dead skin cells to smooth and brighten dull skin, unblocking pores and reducing fine lines and wrinkles by increasing collagen density. The results tend to be cumulative, but due to their exfoliating action, products containing acids can leave your skin looking immediately refreshed too.”
So you’ve got both short term and long term gains in the sweep of a cotton pad. Aesthetic doctor Dr David Jack highlights a few other acid perks:
“The skin should generally be at an acidic pH to inhibit the growth of damaging bacteria and encourage the growth of good skin bacteria. In addition the acid pH sustains an optimum level of oiliness in the skin, ensuring correct function of the sebaceous (oil) glands in the skin and improving the skin’s barrier function.”
In essence, whatever your skincare aims, from keeping blemishes at bay to revving up collagen synthesis, an exfoliating acid can play a vital role in your regime, and if you’re still not sold on the gentle efficiency of many 21st century formulations, doctor in dermopharmacy and founder of Lixirskin Dr Colette Haydon has some words of reassurance:
“Acids were once associated with strong and aggressive chemical peels, but we’ve since discovered how to formulate and combine them more effectively as they have a wonderful synergetic effect, and they’re now rivalling everyday ingredients for a key place in the bathroom cabinet.”
When looking to stock said bathroom cabinet, however, Dr Jack emphasises that there are some key considerations to take into account rather than just picking an ‘off the peg’ acid option:
“On reading the label, you need to look at the type of acid being used and whether it is suitable for your particular skin type or condition, consider the pH at which it is supplied and stabilised, and be aware of the strength of the acid in the preparation.”
Which naturally prompts the question...
Which exfoliating acid is right for me?
We can’t give you a failsafe personalised prescription, but the following acid vs. skincare needs guidelines can help you to find a smooth operator that will leave skin healthy and balanced rather than raw and angry. Also, be aware that there are three acid families to get acquainted with:
AHAs: alpha hydroxy acids include glycolic, lactic, mandelic, malic, tartaric and citric, although as skincare expert Paula Begoun points out, the latter is technically lemon juice, which tips skin too far on the acid pH spectrum. AHAs are particularly helpful if you’re trying to create even skintone and for refining to skin’s surface to make it more radiant.
BHA: the lone ranger salicylic acid makes up the one man band of beta hydroxy acids, but it goes places that AHA can’t in that it penetrates the pore lining and is “oil soluble” according to Paula. It also exfoliates and hydrates and can help to minimise the appearance of pores, shrink spots and is generally suitable for most skin types.
PHAs: Poly hydroxy acids include lactobionic acid and gluconolactone, and their large particle size means that they penetrate more slowly than the likes of high strength, fast action glycolic acid (an AHA as above), offering up a gentler means of exfoliation that’s ideal for those of us with a weaker skin barrier.
Now that you’ve met the three acid dynasties, here’s what to have on your radar according to your skin type.
We’ll start low and slow- if you have a tendency towards the sensitive, or are new to using exfoliating acids full stop, Dr Kluk thinks that ‘baby steps’ are best:
“If you are thinking about introducing an acid to your skincare routine, my advice would be to start with a single product, pick the lowest strength you can find and introduce the product gradually.”
As for exfoliating acids suited to delicate skin, Dr Kluk suggests mandelic acid, as it’s helpful “for increasing radiance with minimal downtime by providing superficial exfoliation to brighten dull skin. The larger particle size means that it doesn’t penetrate as deeply and may be better tolerated by reactive skin types.”
Dr Jack also recommends azelaic acid for reactive skin, as “it has been shown to reduce both redness dryness, and boasts multiple benefits while remaining one of the least irritating acids.” If you suffer from rosacea, Dr Jack advocates azelaic acid in particular.
The Ordinary Azelaic Acid Suspension 10%, £5.50 for 30ml
A simple fragrance-free formulation, this brightening gel helps to bring down rosacea associated redness while providing light exfoliation and high strength antioxidant prowess.
Medik8 Cream Cleanse™, £18 for 200ml
If you’re an acidic beginner and want to dabble in a wash-off product, this mandelic acid based exfoliating cream cleanser is ideal for dry, sensitive skin. Bear in mind, however, that if you’re looking for peel-like results, it won’t happen from a cleanser, as Dr Jack underlines that “usually acids need to be on the skin for a certain amount of time to optimise their effects”.
Dry or dehydrated skin
Dr Kluk extols the virtues of lactic acid if your skin is parched as “it’s an excellent humectant so it’s great for improving hydration as it draws moisture into the skin, as well as exfoliating to smooth out rough, flaky and bumpy skin.”
ELEMIS Dynamic Resurfacing Facial Pads, £39 for 60 pads
Pre-soaked lactic acid pads that also contain a prebiotic ferment to boost healthy bacteria on the skin’s surface.
Oily, acne prone skin
Dr Kluk would steer you towards salicylic acid, as “it’s best for oily, congested skin and useful for eliminating blackheads by unblocking pores. It also soaks up extra shine and can be applied directly to spots- its anti-inflammatory properties can make quick work of nasty breakouts.”
Dr Jack also notes that “both glycolic and lactic acids have also been shown to reduce oiliness and help to rebalance levels of good bacteria in the skin.”
Paula’s Choice Skin Perfecting BHA Lotion, £26 for 100ml
Our office walls may as well be painted with this stuff, we love it that much. Instantly cooling and calming, the light salicylic acid based cream literally knocks spots off when used regularly. I keep it to my nightly routine and am especially diligent with my SPF application in the morning.
Alpha H Liquid Gold, £33.50 for 100ml
This is strong 5% glycolic stuff, but it’s renowned for evicting acne causing bacteria while also diminishing the appearance of scarring over time. Start seriously gently: once a week is plenty for beginners.
You can probably take your pick depending on where your skin is at at any given time (for example lactic on the cheeks, salicylic on your t-zone), but azelaic acid can step up here too according to Dr Kluk:
“It’s useful if you get breakouts, but less likely to irritate the skin than salicylic acid if your skin type is combination rather than oily.”
If you’d like to dip your toes into a different acid, phytic acid is famed for its detoxifying effect according to Dr Haydon, or if your skin is going through a rough patch, call on the soft powers of a PHA.
Lancer Caviar Lime Acid Peel, £90 for 50ml
A potent phytic and glycolic acid based skin hoover, this powerful once a week treatment should be left on for ten to fifteen minutes max. If you’re after at-home resurfacing that’s perceptible after a single use, it could be for you, but sensitive skins steer clear.
Lixirskin Night Switch PHA/AHA, £20 for 15ml
A three pronged skin renewer, this serum contains lactic acid to promote hydration, lactobionic acid for its protective antioxidant capacity and phytic acid to assist general declogging and leave skin soft, not sore.
How should I use an exfoliating acid?
Dr Kluk puts forward a nocturnal acid approach first and foremost:
“The type of formulation you choose really depends on the rest of your routine, but as acids can make your skin more sensitive to the sun, it may be a good idea to start off with a serum or ointment at night after cleansing and before moisturising, and always remember to use SPF the following day.”
As for formulation, Dr Jack favours leave-on serums, toners or lotions:
“If acids are left on the skin for too little time they don’t do anything, but too much time at high strength and they risk irritating the skin and even causing burns. Most commercially available acids in skincare tend to self ‘neutralise’ anyway, so the risk of burns is practically zero. I like serums as a way of applying acids rather than cleansers per se, as they tend to be left on the skin for the ideal period of time.”
Practically, it sounds blindingly obvious, but reading the label will get you far:
“The main thing is to use acids sensibly, following the instructions given on any skincare product and not using the more frequently than instructed! I would also never use strong acids on broken skin or burns.”
Exfoliating acid caveats
Back to reading the label- Dr Haydon drills down on the specifics:
“One thing that you should always be mindful of when purchasing acids is that EU regulations tell us we shouldn’t use anything higher than a 10% acid and that the pH level should be above 3.5%. Always use an acid responsibly and I advise only applying acid at night, rather than when you’re exposed to the sun.”
If you’re suffering with a skin condition or have extremely dry skin, Dr Kluk advises a ‘better safe than sorry’ outlook where any acid is concerned:
Ditto becoming your own bathroom mixologist isn’t to be recommended:
“Care should also be taken with combining acids, unless you are a seasoned user who has built up some tolerance already, as the risk of peeling, redness, stinging or burning becomes much higher.”
Be wary if you’re on the retinol wagon too:
“I would advise strict caution before introducing an acid if you are already using other potential skin irritants, such as retinol.”
Otherwise, AHA moments are to be encouraged.
Book an appointment at Dr Jack’s new Facial Bar at Neville Hair and Beauty