These shampoos are sulfate-free

There are so many beauty terms that it can make your head spin. Confused as to what it all means? Our Glam Glossary will help you sort it all out. Follow Allison each week in her quest to decode popular beauty terms, from Alpha Hydroxy Acids to Zinc Oxide.

Sodium Lauryl Sulfate

What it is: Sodium lauryl sulfate (SLS) is a strong detergent surfactant that’s created by a reaction between lauryl alcohol and sulfuric acid.

Where you see it: Toothpaste, shampoo, body wash, moisturizer, dandruff treatment, facial cleanser, foundation, deodorant.

What it does: Have you ever heard the idiom that oil and water don’t mix? It’s so true, and I’m sure we’ve all learned this in more ways than one. Well, as a surfactant, SLS lowers the surface tension of a liquid or the surface tension between two liquids – so in the case of personal care products, SLS is on board to make sure that the water from your shower and the oil, dirt, and dead skin cells on your body end up going home together. Think Patti Stanger pumping up the millionaire and the gold-digger before their date to make sure sparks will fly. (What? Not a good analogy? But they both use alcohol!)

Is it safe? I thought you’d never ask! While SLS appears on the Federal Drug Administration’s list of most frequently used cosmetic ingredients, not everyone is happy about it. A trend among the information available from associations and government agency sites about SLS was the call out a certain nasty little “internet rumor” apparently being spread about SLS. According to the American Cancer Society, the blabber-mouth e-mail (it feels like I’m back in middle school) goes a little something like this:

“Check the ingredients listed on your shampoo bottle, and see if they have this substance by the name of Sodium Laureth Sulfate, or simply SLS. This substance is found in most shampoos, and the manufacturers use it because it produces a lot of foam and it is cheap. BUT the fact is that SLS is used to scrub garage floors, and it is very strong. It is also proven that it can cause cancer in the long run. I went home and checked my shampoo (Vidal Sasoon), it doesn’t contain it; however, others such as Vo5, Palmolive, Paul Mitchell, the new Hemp shampoo, etc. contains this substance.”

Oh to be young and slanderous again! Sodium lauryl sulfate and sodium laureth sulfate are chemical cousins, the ACS says, but SLS refers to sodium lauryl sulfate, and SLES is used to describe sodium laureth sulfate. Both are surfactants, as we’ve learned about above, and both are acknowledged as “irritants in patch testing concentrations of two percent and greater,” according to the Cosmetic Ingredient Review’s safety review, which also includes a response to the gossipy e-mail. Because SLS is a powerful surfactant, it’s not surprising that it’s found in industrial floor cleaners, car wash soaps and engine degreasers – but obviously in much higher concentrations than personal care products see.

The e-mail isn’t totally off-base in every concern. By that, I mean that a study published in the Journal of the American College of Toxicology in 1983 did find that SLS “causes severe epidermal changes to the area of skin of mice to which it was applied.” The study also suggested that heavy deposition of SLS in hair follicles could damage said hair follicles. However, it still ultimately concluded that SLS “appears to be safe in formulations designed for discontinuous, brief use followed by thorough rinsing from the surface of the skin. In products intended for prolonged contact with skin, concentrations should not exceed one percent.”

The Australian Department of Health and Ageing agrees, and so do others.

Photo: Product collage of L’Oreal, Bed Head