Alcohol is widely used in skincare formulations because of it's versatility. It functions as a solvent (thinner), emulsifier (blender), buffer (PH balancer), stabiliser (prevents separation), preservative or penetration enhancer.
There is a common misconception that all alcohol is bad. In fact there are three types of alcohol in skincare. Simple alcohol, fatty alcohol and aromatic alcohol.
Simple alcohols also go by the names methanol, ethanol, isopropyl alcohol and denatured alcohol (SD alcohol or alcohol denat). They are used to stabilise a formula, dissolve surface oil and gives a formula a 'pleasant' aesthetic. However the quick evaporation qualities causes the skin to dry out and ultimately weakens its protective barrier.
Although alcohol has antiseptic properties, it also destroys good bacteria and applying alcohol to an open wound can be incredibly harmful. Medical professionals use sterile water, saline or iodine to clean open wounds instead of alcohol.
Simple alcohols are used as a penetration enhancer and although it helps the absorption of certain ingredients, it does so by destroying the skin's barrier and does more long term harm than good.
Small amounts of alcohol (3%) applied to skin cells in lab settings over a period of days causes cell death by 26%. Certain skincare products contain alcohol at far greater concentrations than 3%.
Simple alcohols should only be used in extremely low quantities, if at all and appear at the very bottom of ingredient listings. Cheap toners or astringents that target oily skin or acne prone skin can be too harsh and long term use encourages sebum overproduction to counteract the drying out effect. The use of simple alcohols impacts the pores and compromises the skin barrier causing more skin irritations. Even in small quantities, this alcohol group has the ability to stress the skin.
The second group of alcohols are called fatty alcohols. They are found in skincare formulations with names such as caprylic alcohol, cetearyl alcohol, cetyl alcohol, decyl alcohol, lauryl alcohol, isostearyl alcohol and stearyl alcohol. They are thick and waxy and are used as emollients. Their occlusive properties makes them good for slowing down loss of water. This group of alcohol is generally non irritating.
Finally there are aromatic alcohols. These function as a preservative and are usually derived from essential oils. They give off a nice scent and are somewhat harmless if used in small quantities at the bottom of the ingredient listing. It has similar characteristics to simple alcohol so too much of it can irritate the skin.
To summarise, be mindful of the type of alcohol in your skincare formulations. Simple and aromatic alcohols can harm your skin and incite inflammation in the long run. Fatty alcohols are not harmful and provides moisturising properties. However it's more important to choose products formulated with ingredients that work to nourish and heal the skin instead of having alcohol as the main ingredient.