Sodium Lauryl Sulfate
What is it?
Sodium lauryl sulfate (SLS) is a surfactant and detergent (cleaning agent) created synthetically. It is not to be confused with sodium laureth sulfate (SLES), a more gentle surfactant used in similar products.
What is it used for?
SLS is used in a range of domestic cleaning products, personal hygiene products (such as toothpaste), haircare and skincare products. In skincare it is primarily used in cleansing products for its ability to create a lather when it comes into contact with water, though it can also be used as an emulsifier.
What are the pros and cons of using it?
Continued use of SLS has been shown to cause skin irritation in some people, including dryness, redness and eye irritation. Prolonged use is thought to increase skin sensitivity, so those who already suffer from sensitive skin issues might do best to avoid it. However SLS has been the subject of some very negative reports which do not have substantial evidence behind them – for example there is no proven link between SLS and cancer. SLS could have a negative impact on the skin in terms of sensitivity, but it is not as dangerous as some online reports suggest. For those who like their products to lather, SLS certainly provides a deep and thorough clean – however SLES is a gentler alternative which might be preferable.
Which products will I find it in?
SLS is a frequently-used ingredient in foaming cleansers in particular, so if you want to avoid it be sure to check your product labels. For SLS-free cleansers that still offer that squeaky-clean feeling, try Aurelia Probiotic Skincare Miracle Cleanser, Ren Evercalm Gentle Cleansing Milk or Sunday Riley Ceramic Slip Cleanser.