Sodium Lauryl Sulphate and Sodium Laureth Sulphate

beauty blogLast week I was asked by Cynthia (also known as Miss Lipgloss) if I could let her know what the difference is between Sodium Lauryl Sulphate and Sodium Laureth Sulphate. It struck me that in no time there were more than a 100 people who had reacted to the piece on her blog.

This shows that there is a lot of confusion about SLS and SLES (and that Cynthia’s blog is read very much)! So below, you can also see my story about the two ingredients that make your soap, shampoo or face cleanser foam up well. And that have perhaps turned your skin into sand paper….

Sodium Lauryl Sulphate and Sodium Laureth Sulphate

Both Sodium Lauryl Sulphate (SLS) and Sodium Laureth Sulphate (SLES) are surfactants (or surface active substances). Surfactants are compounds which, when combined with water, can be used to dissolve oil or grease; so you can clean your skin with surfactants. Because surfactants reduce surface tension they produce more foam and their products are more pliable.

Why it is better not use surfactants…

The main disadvantage of surfactants is that apart from sebum and dirt they can also readily dissolve the skins natural oil. Through this the barrier function of the skin can become upset and you may then suffer with dry, flaking and dehydrated skin. You may also have problems with spots and red patches.

Skin irritation due to Sodium Lauryl Sulphate

Despite all the negative comments about Sodium Lauryl Sulphate there is no evidence that it is cancerous or toxic. Sodium Lauryl Sulphate is, however, the absolute king of the skin irritation world. It has such an irritating effect that it is now the standard substance used to cause irritation to small areas of skin so that the soothing effects of new cosmetic ingredients can be measured. Just a low concentration of Sodium Lauryl Sulphate breaks down the outermost skin layer. Therefore it is sometimes used to help other active ingredients penetrate deeper into the skin. But whether it makes you more beautiful…

In conclusion Sodium Lauryl Sulphate (or Sodium Dodecyl Sulfate) is definitely a substance to be avoided. Sadly, it is still being used by manufacturers because it is a very cheap ingredient and produces a lot of foam.

And Sodium Laureth Sulphate?

Many people do confuse Sodium Lauryl Sulphate with Sodium Laureth Sulphate. Sodium Laureth Sulphate is, just like Sodium Lauryl Sulphate, a surfactant, but has a much less irritating effect. This substance is also added to products in order to make them produce foam. You still need to be careful with Sodium Laureth Sulphate if you have sensitive skin. Whether it irritates your skin depends on the concentration added to the product and if there are replenishing oils contained in the product. A good general rule is that if your skin feels tight after washing then the product is too harsh for your skin. In any case, don’t use a product containing Sodium Laureth Sulphate too often, don’t use too much of it and rinse it off thoroughly with water.

Regards Jetske

(Dr. Jetske Ultee-Research Physician Cosmetic Dermatology)

You can also read the blogs:
A Sensitive Skin‘,
A Healthy Barrier Function, a Healthy Skin’,
Luxury Ingredients for Your Skin’,
Help with Choosing Your Make-Up Remover’,
The Cleanser’ and
All-In-One Products‘.