Introducing AHAs, or Alpha Hydroxy Acids! 

AHAs are a family of acids which are used to exfoliate skin.  They help remove dead skin cells, but without potentially causing damage by using a physical exfoliator like a scrub, which can cause micro tears in the skin if it’s used too harshly.  

Some of the most commonly known AHAs are glycolic, lactic, mandelic and citric acid.  They’re found in a lot of different products, and in various strengths.  AHAs are water soluble, meaning they can’t break through the skin’s natural oils, so they can’t penetrate pores as deeply.  They’re best suited for surface exfoliation rather than cleaning out pores like BHAs (or Beta Hydroxy Acids).  

AHAs are perfect for giving a more glowing complexion, and help fade scaring & pigmentation.  They lift off the dead skin cells which make skin look dull and block pores, and break down the desmosome connections (or glue) which attaches the dead skin cells to the healthy skin underneath.  

Dead skin cells can exacerbate the appearance of fine lines & wrinkles, so AHAs have anti-aging properties. They also increase the skin’s collagen production so they can help reduce new lines forming too – win win!

AHAs exfoliating and removing dead skin cells from the skins surface

Getting started with AHAs

Whilst using acid exfoliators doesn’t come with the risk of causing small tears in the skin like physical exfoliators do, acid overuse can damage the skin’s barrier. 

It’s best to start low, ease your skin into and then build it up.  The type of acid you chose is important, as acids with a larger molecule size don’t penetrate the skin as quickly, meaning a lower risk of irritation.  Lactic acid has larger molecules than glycolic acid, so it’s less likely to irritate skin. Lactic acid also has humectant properties which attracts water into the skin, making it a really good beginner acid.  

The percentage of the active ingredient in a product is also a factor. Although it might be really tempting to start on the highest % in the hope you’ll get results more quickly (trust me, I’ve been there!).  Diving in to a high percent is the quickest road to skin irritation and a damaged skin barrier. Start low, and then once you’ve used up a bottle look at replacing it with the next percentage up.  

It’s really important to use an SPF everyday anyway, but especially if you start introducing AHAs into your routine.  They increase photosensitivity, which means they make skin more sensitive to UV damage, so a broad spectrum sunscreen which protects from both UVA & UVB damage is a must.  

How to fit acids into your skincare routine

AHAs are water soluble, which means they can’t pass through oil.  Applying them onto thick, oil based products means they just won’t be as effective.  It gives them the best chance of working use right after you’ve washed your face. Then once they’ve sunk into your skin carry on with the moisturisers and creams which you already use.  

As they cause photosensitivity it’s best to apply them in the evening and let them do their work overnight (but still remember the sunscreen in the morning!)

If you already use products like retinoids, BHAs or Benzoyl Peroxide, be cautious applying AHAs at the same time.  It comes back around to protecting your skin barrier, so alternate the actives on different days. Once your skin is used to tolerating them you could use a BHA in the morning and an AHA in the evening.