AHAs, BHAs and PHAs - what's all the fuss?
Updated: Apr 17
The idea of applying acids to your face doesn’t exactly come as a natural thing to do for most people. For the vast majority of the population, myself included, my exposure to acids was in high school chemistry class and reading about the destructive effects of acid rain as a kid. But just like almost all of my previous blogs, we have to learn more about what exactly people are talking before drawing any conclusions. So, lets take a dive and find out what could be the benefits of the right kinds of acids to be include as part of our beauty skincare routine.
Let’s start by first outlining the 3 major acids which are most likely to be part of your skincare process: Alpha Hydroxy Acids (AHAs), Beta Hydroxy Acids (BHAs) and Polyhydroxy Acids (PHAs).
AHAs are the most commonly used of these chemical compounds (sounds better than acid I know). They are found in over-the-counter products and are used for exfoliation. You may seem them listed as glycolic, tartaric, lactic and citric acids. All of these are AHAs, each with their own claimed area of improvement. Overall, they are the home version of chemical peels which are normally done in clinicians' offices under medical supervision. The difference between the two has to do with the concentration of the acid. Standard products have AHA concentrations as low as 4% and maybe up to 10%. The products used by dermatologists are usually upwards of 70%. AHAs are mostly used to address fine lines, uneven skin tone, enlarged pores and mild hyperpigmentation such as age spots and scars. They help exfoliate the skin by removing dead skin cells allowing newer, stronger and firmer cells to take their place thereby rejuvenating and giving you smoother, younger looking skin.
BHAs, on the other hand, more used for acne and sun damage. They tend to go deeper into your skin and has been claimed they do a better job without the occasional irritation associated with the use of AHAs. BHAs may be best suited for oily skin and lower concentrations should be considered for more sensitive skin. A general rule of thumb is that if you want to tackle acne related issues, look for BHA. FYI: BHA ingredients may also be listed as salicylic acid. As mentioned before citric acid is mostly classified as an AHA, some formulas of citric acid are BHAs.
As mentioned though both AHAs and BHAs are designed to exfoliate and rejuvenate the skin. Used in combination they could show results of fuller looking skin due to the increased collagen production. Some products even combine the two. But be careful of overdoing as they could cause dryness. Some experts recommend to perhaps use one formula in the morning and another at night as part of your evening routine. Or even to simply apply the specific area of your face you want to address.
The final one of these chemical compounds were going to look at today are PHAs, the relatively new kid on the block, or on the periodic table if we want to take this chemistry class analogy all the way home. PHAs, which are commonly labelled gluconolactone, galactose and lactobionic acid, are considered as the second generation of AHAs. They are still exfoliants but have different molecular structures. The molecules which are the building blocks of PHAs are much bigger than AHAs and BHAs. This means that they can’t penetrate the skin as deeply and work exclusively on the surface of your face. PHAs attract water molecules which in turn moisturize your skin. The end result is that PHAs normally offer less possible irritation compared to their cousins. They still remove dead skin cells which makes your face look smoother and more even in tone. The other cool effect of PHAs is that they fight glycation which is what happens when sugars attach themselves to the collagen of your skin. This process weakens the skin and lowers elastin levels. Finally, PHAs are antioxidant rich which means the stimulate epidermal growth and repair resulting in plumper younger looking skin.
So, what’s the conclusion here? First, I should have paid more attention during chemistry class. Second and most relevant to our shared beaty journey is that AHAs, BHAs and PHAs are all skincare ingredients we should be aware about and we should understand what they do to our skin. AHAs are used for normal to slightly dry skin and are great exfoliants. BHAs work best for oiler skin types, work they way into blocked pores and provide great results for acne. Finally PHAs are your gentler, softer alternatives to consider, provide great moisturizing benefits and are especially well suited if you have very sensitive or dry skin.