In 1934, when Proctor and Gamble launched the first synthetic shampoo ‘Drene’ using the ingredient “triethanolamine alkyl sulfate” it changed the hair care industry forever.[i] The ingredient was already known to be a good surfactant that reduced surface tension for cleaning textiles, carpets and cars in car washes. The sulfate accomplished this because it is partially lipophilic (lipid loving) and partially hydrophilic (water loving). The “fat loving” portion of the polymer picked up the grease and grime, while its “water loving” portion enabled the captured dirt to be easily rinsed out. In addition, this sulfate was very good at trapping air during agitation to create a nice lather that promoted easy dispersal of shampoo throughout the scalp.
While this new ingredient to the personal care industry brought exciting new performance properties to the market, we shouldn’t be too surprised that a product used for carpet cleaning was gradually deemed to be too harsh for routine hair care. In fact, sulfate technology has improved considerably since then with a number of less harsh sulfates identified that still provide excellent lathering and cleaning capabilities. Fast forward to today, many stylists consider even these milder sulfates to be too harsh, drying, and damaging to color-treated hair, while others think such concerns are overblown and a good lather necessary to get the job done right. Who is right and who is wrong? In this blog we’ll look at the arguments for both sides, give you the facts as we know them and let you be the judge.
What is the purpose of a shampoo?
Before discussing the pro’s and con’s of sulfate-based vs. sulfate free shampoos, it is important to understand why we use a shampoo to begin with. Everyone knows the simple answer—to clean the hair—but let’s get a little more specific. As Dr. Zoe Draelos writes in the International Journal of Trichology:
“A shampoo is technically designed to clean the scalp of sebum and prevent the development of folliculitis and seborrheic dermatitis [dandruff]. Shampoos are intended to rid the hair of sebum [our hair’s natural oil], sweat components, desquamated stratum corneum [dead skin], styling products, and environmental dirt. The idea of beautifying the hair is really a secondary concern that is primarily addressed by a conditioner.”[ii]
So shampoos are not just about the hair itself but maintaining a proper balance of hair and scalp health. In particular, sebum—our hair’s natural oil—is in many ways the ideal conditioner and shine agent; however, unfortunately, if left unchecked, fungus and bacteria can feed on it leading to dandruff and other health issues. The frequency of the need for a comprehensive deep clean depends on many personal and environmental factors, but it is clear everyone should do so at least somewhat regularly. Sulfate-based shampoos promote the best lather possible for dispersing cleaning agents in the hair, but recently developed sulfate-free surfactants exist today that offer ability to achieve a deep clean too.
The Pro’s and Con’s of Sulfate-based Shampoo
While some people hate sulfates, few don’t like a nice rich lather when shampooing. In fact, rumor has it that at Ralph Lauren’s Fall 2017 Fashion Show, celebrity stylists fed up with the dry-shampoo and sulfate-free shampoo craze had a mini-riot in defense of traditional sulfate-based shampoos.[iii] A lather creates a clear signal of where you are cleaning and sometimes you can even see the dirt and grime in the foam before it disappears down the drain. In addition, a good lather means you don’t have to work as hard to clean your scalp. Nothing seems to be better than sulfates for creating that effect. A lot, maybe even a majority, of consumers prefer shampoos that produce a lot of foam, so don’t feel ashamed if you do.[iv]
Sulfates have been accused by some of being carcinogenic, but the vast majority of scientific studies reject this claim.[v] In addition, sulfates readily biodegrade in the environment, another favorable sign for their use. However, sulfates are harsher than many hair care ingredients. In fact, for people with sensitive skin sulfates have been known to cause irritant contact dermatitis (ICD) and some people can experience allergic contact dermatitis (ACD) to sulfates.[vi] As a result, the American Academy of Dermatology recommends people with eczema or especially sensitive skin not use sulfate-based products.[vii] According to Ada McVean, another problem with sulfates is, “that they’re a bit too good at their job as surfactants.”[viii] Why? Because “[sulfates] strip natural oils from the scalp and hair removing natural moisture, which can make hair dry and brittle.”[ix] Finally, sulfates have come under attack by stylists for damaging colored hair. While this claim is hotly debated and dependent upon individual formulations, stylists often recommend you go with a sulfate-free shampoo after chemical treatments such as: coloring, keratin or a Brazilian blowout.[x]
The Pro’s and Con’s of Sulfate-free Shampoo
For the past two decades a lot of scientific work has gone into identifying sulfate-free surfactants that can deliver the suds. Those efforts have paid dividends as there are a number of mild sulfate-free options that can produce a lather. However, even with as much improvement as there’s been, there’s still no question that lather-for-lather sulfate-based shampoos win the foaming contest hands down. Having said that, when applied properly, today’s better sulfate-free shampoos can actually clean just as well as sulfate-free shampoos. In fact consumers need to be careful, some “sulfate-free” shampoos use an ingredient called olefin sulfonate which cleans well but is just as harsh as sulfates on hair.[xi] Additionally, some sulfate-free products contain sodium chloride which is considered by some to be a “keratin-killer” if used in excess.[xii] Nevertheless, just as sulfate-based shampoos win the foam contest, sulfate-free shampoos win the battle for mildness and gentler impact on hair. This means that if you have chemically treated, dry or frizz-prone hair, sulfate-free shampoo is the recommended path for you.
Conclusion
There are strong arguments to be made for both sulfate-based and sulfate-free shampoos. Unless you have eczema or an allergy to sulfates, you can use either shampoo type. In addition, the quality of the ingredients and formulation play a very important role in overall shampoo performance. Desert Botanicals is developing top performing paraben-free and cruelty-free sulfate-free and sulfate-based shampoos so consumers have a choice on which they use. In sum, if you prefer a rich lather that facilitates an easier clean a sulfate-based shampoo is the way to go, while if you have color-treated or naturally frizz prone hair a sulfate-free shampoos is a better option.
