Did Someone Say “SLS-Free”?

What is SLS?

Sodium lauryl sulfate (SLS) is a surfactant, meaning it has an effect primarily on the surfaces it touches. It is used in a variety of products, including food thickeners, toothpastes, and floor cleaners. It stands out for its foaming function.

What Does SLS Stand For?

SLS (Sodium Lauryl Sulfate), also known as sodium dodecyl sulfate, is derived from coconut and/or palm kernel oil or synthetically and is used as an emulsifier in various formulations. ¹

Are SLS and SLES the Same?

Sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) are anionic surfactants and detergents found in many cleaning and personal care products.

Surfactants reduce the surface tension of water, allowing oil and dirt to be removed more easily. For example, dishwashing detergents cleanse oils, while shampoos remove accumulated oil from hair.

SLS and SLES help to create foam in cleansing and skin care products to achieve the desired effect. The main difference between the two is that SLES undergoes an additional process called ethoxylation, making it gentler on the skin. ²

Which Products Contain SLS?

SLS is found in a wide range of products. It is a surfactant with many different functions used in a variety of products including food, detergents and cosmetics, but in skin care it acts as a cleansing agent.

Product Groups Containing SLS

Many products we use in our daily lives contain SLS. These can be listed as facial cleansers , body washes and shower gels, shampoos, hand soaps, detergents, toothpastes and cleaning products for your home.

Is SLS Harmful?

There are many different opinions about the harmfulness of SLS. Its negative effect on the skin barrier does not seem to be a subject open to discussion. Studies have shown that it causes deterioration in the skin barrier function.

SLS Harms

The use of SLS in consumer products is regulated and its potential for irritation is evaluated in the context of the full product formulation.

SLS-free cosmetics are formulated to be gentler on the skin, which can reduce the risk of irritation and allergic reactions. A study published in The Journal of Clinical and Aesthetic Dermatology concluded that water-based creams without SLS have a lower potential for irritation than water-based creams containing SLS. ³

Another study conducted in 2021 used patches containing SLS on a group of women. Analysis before and one day after removing the SLS patch revealed an increase in skin redness and a decrease in skin barrier function.

It has been observed that an impaired skin barrier function and dehydration caused by the SLS patch disrupt the delicate balance of the skin microbiota leading to skin bacterial community dysbiosis. ⁴

SLS-Free Products

SLS-free products offer many potential benefits in terms of being skin-friendly and minimizing the risk of allergic reactions. Using SLS in toothpastes, especially those that come into direct contact with oral tissue, can lead to disruption of oral balance. While the importance of oral health, which is the first step of digestion, is an undisputed fact, it is possible to provide effective cleaning with safe ingredients that are free of doubt.

Resources

1. https://www.chemicalsafetyfacts.org/chemicals/sodium-lauryl-sulfate-sls/
2. https://www.products.pcc.eu/en/blog/sles-and-sls-what-are-these-substances-and-where-are-they-used/
3. Mei-Hsia Chan M, Tan LS, Leow YH, Goon AT, Goh CL. Comparison of Irritancy Potential of Sodium Lauryl Sulfate-free Aqueous Cream to Other Moisturizers: An Intraindividual Skin Occlusive Study. J Clin Aesthet Dermatol. 2019 Jul;12(7):52-58. Epub 2019 Jul 1. PMID: 31531162; PMCID: PMC6715333.
4. Leoty-Okombi S, Gillaizeau F, Leuillet S, Douillard B, Le Fresne-Languille S, Carton T, De Martino A, Moussou P, Bonnaud-Rosaye C, André V. Effect of Sodium Lauryl Sulfate (SLS) Applied as a Patch on Human Skin Physiology and Its Microbiota. Cosmetics. 2021; 8(1):6. https://doi.org/10.3390/cosmetics8010006