SLS also known as Sodium Lauryl Sulfate, and its bestie SLES (Sodium Laureth Sulfate) have been getting a bad rep for a while now, but do you know why?
WHAT ARE SLS AND SLES USED FOR?
They are used as surfactants and emulsifiers – the stuff that makes soap, shampoos, shower gels, toothpastes, laundry detergents, and household cleaning products foam – these help to clean dirt and grease from clothes, skin, hair, etc, so that they can get rinsed away easily. So far so good, we want to be clean and have clean things.
Unfortunately for some, SLS and SLES can have a drying effect, stripping away the natural oils on skin and in hair, leaving behind dry and sometimes itchy skin, creating a weaker barrier, making it more permeable to wanted and unwanted ingredients. When SLS and SLES are used in more than just rinse off products, and are included in body moisturisers and other leave on products, the problem with dry and itchy skin can be exacerbated. Eczema sufferers have reported their skin is better without SLS and SLES.
ARE THEY BANNED FOR USE IN COSMETIC PRODUCTS?
Note, they are not banned substances, and for wash off products, they have been deemed suitable by Allergy Certified, who have a more stringent set of criteria when it comes to allergens and skin irritants. COSMOS certifies products containing SLS, and I believe they certify for both wash off and leave on products (Ecocert and Soil Association are both accreditation bodies operating under COSMOS standards). COSMOS do not certify SLES at all.
I personally steer clear of SLS and SLES altogether because it has a noticeable drying effect on my skin, leaving it tight, and on my scalp, leaving it itchy. Plus, I don’t like the idea of using something as harsh as what is used in laundry detergent and household cleaning products to get my skin / hair / teeth clean.
Of course, each individual will have sensitivity to ingredients that are unique to them, but if you have dry, itchy skin then it may be worth checking to see if SLS or SLES is in your rinse off products or even leave on ones, and try ones without them to see if it helps. Only you will know what is suitable for your skin and hair.
Skins Matter have a list of products which do not contain SLS or SLES, and is a good resource for anyone looking to remove these ingredients from their routine. Their list is not exhaustive, but is a good starting point.