How To Use Acids In Your Skincare Routine

The idea of putting acids on your skin sounds scary, right? It kind of goes against everything you learned in high school chem class… In fact, using acids (the right ones) in your skincare routine can completely transform your skin, and target a number of skin concerns, from acne, to scarring, pigmentation, and ageing. 

Get ready to get the glow (and smoother skin) with our handy beginners guide – we’ve covered everything from what they do to when to use them. 

Meet the top ten acids you need to know. 

Glycolic Acid (AHA) 

What does it do? Has a mild peeling effect which exfoliates away the top layer of dead skin cells (which clog pores and cause skin to appear dull and congested). In turn, this process stimulates cell turnover, so your skin starts to produce new, healthier cells to replace them. 

Best for: Scars, pigmentation, dullness, and aging or blemish-prone skin. 

Find it in: Mario Badescu Glycolic Toner

Salicylic Acid (BHA) 

What does it do? It penetrates the surface of the skin and dissolves the ‘glue’ that holds cells together – which sounds scary, but basically exfoliates skin and unclogs pores, getting rid of cysts and blackheads. It’a slo has the ability to penetrate through oil so its really effective at reducing sebum production, and it also acts as an anti-inflammatory to calm existing acne. 

Best for: Oily, blemish-prone skin, and blackhead and acne sufferers. 

Find it in: Alpha-H Clear Skin Daily Hydrator Gel

Hyaluronic Acid 

What does it do? Draws moisture into the skin and delivers it deep beneath the skin’s surface for maximum hydration. Each molecule of hyaluronic acid has the ability to hold up to 1000 times its weight in water, so using this acid makes a massive difference in your skin’s health, appearance, and texture. 

Best for: Dry/dehydrated skin – really all skintypes can benefit from this acid as a hydrated complexion is healthier and better prepared to resist breakouts, scarring, wrinkles etc 

Find it in: NIOD Multi Molecular Hyaluronic Complex

Lactic Acid (AHA) 

What does it do? Exfoliates the skin’s surface layer of dead skin cells just as glycolic acid does, but in a much gentler and less-irritating way – so there’s a much smaller risk of redness and discomfort. Over time it helps to improve skin’s texture and brightens its appearance. 

Best for: Sensitive skin which also suffers from breakouts, scarring, and dullness. 

Find it in: The Ordinary Lactic Acid 10%

L-Ascorbic Acid 

What does it do? It’s actually just a fancy way of saying ‘Vitamin C’, which everyone knows is the ingredient to use if you want clearer, brighter skin. Dark spots and acne scars, begone! It’s packed with antioxidants to combat free radical damage and trigger collagen production to smooth fine lines. 

Best for: Anti-ageing, free radical damage, brightening pigmentation 

Find it in: Mario Badescu Vitamin C Serum

Citric Acid (AHA) 

What does it do? Delivers antioxidants to the skin and rebuilds collagen to stimulate the growth of new, healthy cells. These fight free radicals (harmful molecules triggered by sunlight, pollution, and smoking) which cause skin to wrinkle, discolour, and loose elasticity.  

Best for: Preventing early signs of ageing caused by free radical damage. 

Find it in: Holika Holika Good Cera Super Ceramide Mist

Azelaic Acid 

What does it do? It gently exfoliates skin to unclog pores and improve the appearance and texture of the skin’s surface – it’s particularly effective at decreasing redness, bumps, scarring, and can even reduce skin sensitivity. 

Best for: Blemishes, discolouration, and post-acne red marks. 

Find it in: The Ordinary Azelaic Acid Suspension 10%

Alpha Lipoic Acid 

What does it do? Another antioxidant, with all the same antioxidant magic, plus the ability to regenerate other antioxidants, such as vitamins E and C. It also has a skin-soothing effect, so it’s great for sensitive and irritated skin. 

Best for: Improving skin tone and treating ageing skin. 

Find it in: The Ordinary Alpha Lipoic Acid 5%

Ferulic Acid 

What does it do? Yes another powerful antioxidant, this time designed to fight signs of aging triggered by both free radicals and by sun damage, helping skin to regenerate when it’s been over-exposed. It also enhances the efficacy of other vitamins so it’s a great one to layer.  

Best for: Preventing visible signs of ageing and sun damage. 

Find it in: The Ordinary Resveratrol 3% + Ferulic Acid 3%


What does it do? Whilst not technically acids in themselves, retinoids are derived from retinoic acid, a form of Vitamin A. They dissolve and exfoliate dead skin cells, helping to clear the congestion that leads to dullness and acne. What’s more, they trigger collagen production to smooth out fine lines and boost cell turnover. 

Best for: Acne-prone skin and visible signs of ageing. 

Find it in: The Ordinary Granactive Retinoid 2%

Confused by any of these terms? Check out our handy guide to the big skincare buzzwords.


Top Tips

– Don’t layer AHAs and BHAs together (for more combinations to avoid, click here) 

– Don’t layer AHAs with other AHAs – there is such thing as too much 

– Make sure you wear sunscreen every day if you’re using acids regularly (exfoliating your skin increases its sensitivity to sun) 

– Some formulas are designed to be used daily but it’s best to start by using acids 2-3 times a week and building up when your skin is ready 

– Increase frequency of use if your skin no longer reacts as it did when you first used it e.g. no tingling 

– Observe your skin – mild tingling is normal but if your skin becomes red and irritated, reduce usage 


Acid Starter Pack

The Ordinary Salicylic Acid

Use to spot-treat breakouts and stop them in their tracks as soon as you feel them appear. 

Mario Badescu Glycolic Acid Toner

Swipe on nightly to maintain bright, clear skin and fade the red marks left behind by breakouts.

Peter Thomas Roth Water Drench Hyaluronic Cloud Serum

Like a drink of water for your skin, apply this overnight to wake up to soft, replenished skin come sunrise.