Salicylic acid - an ingredient you have probably come across if you have ever Googled "spot treatment" (who hasn't)?!
It is a big player in the skincare industry and has been used for over 2000 years. It is now synthesized chemically, however it was originally derived from willow bark to reduce pain (and is now a starting molecule to synthesize aspirin).
It is often referred to as a beta hydroxy acid (BHA), however this is technically not chemically accurate, rather a marketing term that stuck.
It is actually phenolic aromatic acid, due to its structural properties but this doesn't roll off the tongue so well!! The chemical formula is: C6H4(OH)COOH.
WHAT SKIN ISSUES CAN IT HELP WITH?
Acne treatment, particularly blackheads (open comedones) - due to its ability to unclog pores.
Melasma/ photo-damaged skin - due to its exfoliation properties.
HOW DOES IT WORK & WHAT DOES IT DO?
Mainly as an exfoliant on the stratum corneum (outer layer of skin), by softening keratin, a protein involved in skin structure.
It is also lipophilic - thus it will dissolve in oil. This gives it the ability to penetrate the pore and exfoliate the dead skin cells that build up inside - which is why it is so great for blackheads. It reduces the amount of oil your skin produces (from acne patient studies) which is beneficial if your skin is a bit on the oily side.
Salicylic acid can also combat inflammation & has anti-microbial properties - both fantastic for fighting all forms of acne. We know acne is partially caused by the bacterium p. acnes, so anything with anti-microbial properties is a plus. For the extra science bit - it modulates the expression of COX2 gene expression to decrease the formation of pro-inflammatory prostaglandins.
CONCENTRATIONS & HOW TO USE:
Topical over-the-counter concentrations tend to be around 2%. This is suitable for most skin types to be used regularly, but as always with actives, you want to start slow (a few times a week) and then increase your usage depending on your tolerance.
Salicylic acid is also an extremely popular ingredient in peeling solutions, where you will find a much higher concentration of the acid - around 20-30%.
These are to be used infrequently (once a month or so) as they are much more intense, but can work wonders in helping stubborn blackheads/ acne and also improving the overall texture of your skin. Salicylic acid at these concentrations is administrated by a professional/ physician.
PRODUCT RECOMMENDATIONS:
-CosRx BHA Blackhead Power Liquid (a personal favourite - very effective and much less drying than most solutions on the market)
The Ordinary Salicylic acid 2% (very affordable)
Murad Blemish Control range - they have a variety of fab products, including cleansers, moisturisers, SPFs and targeted spot treatments
Medik8 Pore Cleanse Gel Intense
And that is it! I hope you enjoyed - let me know if you have any questions in the comments :)
Lots of love,
Madeleine xoxo