Is Sulfate-Free Shampoo Really Better For Hair?

Just like gluten or dairy in health-conscious restaurants, sulfates have become a dirty word in hair salons all over the world. "Stay away from them at all costs," a famous celebrity hairstylist once warned me, while another tutted when I told him about the great (yet sulfate-powered) shampoo I'd been using for years: "I mean, it's completely stripping your hair."

Clearly I was washing my hair all wrong, and both incidents made me completely reevaluate those quick five minutes in the shower. Buying any old shampoo at the drugstore would no longer cut it; instead, I was advised to shop my shampoo in-salon or from high-end beauty retailers, paying special attention to the ingredients list on the back. Because if everyone was bashing sulfates — from hairstylists to the shampoo brands themselves — they had to be really bad... right?

Not long ago, though, I ran out of the trusty sulfate-free shampoo I'd been relying on to keep my hair soft, glossy, and healthy. Rifling through my bathroom cupboard for a quick substitute, I picked up the nearest bottle of shampoo, but as it lathered, panic set in. As I skimmed the ingredients, bubbles streaming into my eyes, the words "sodium lauryl sulfate" jumped out at me. But it was too late. I just had to get on with it.

I had rinsed, blowdried, and styled as normal when I suddenly realized that my hair had never felt cleaner. Like a second-rate shampoo-ad model, I ran my fingers through my newly strong, soft strands all day and continued to use the shampoo until the very last drop. It had to be the sulfates — but how?

"Sulfates are detergents that are very beneficial in products within the hairdressing industry," says Wella education expert Sophie Ruggiero. "They are active ingredients that make shampoo foam, and they really work to clean the hair's surface as well as the scalp."

"If your hair feels quite heavy then it’s important to carry out a deep cleanse," explains award-winning hairstylist Paul Edmonds. "Sometimes hair feels cleaner and lighter if you use a product that harnesses sulfates occasionally. They work best on thicker hair types, as they allow it to become more manageable and lightweight."

Why, then, are we all so wary of them? "They tend to have a bad reputation," Ruggiero says, mainly for drying out hair and zapping color. Those with sensitive or excessively dry skin may also find that sulfates increase irritation when not rinsed off properly, and in that case, investing in a sulfate-free shampoo might be a better option. "But the amount that is used in a shampoo is actually very minimal," Ruggiero continues. "Most shampoos are packed with conditioning and caring agents which ensure the client gets the cleansing they require from shampoo, plus nourished hair." These substances are what Edmonds refers to as "buffers."

Take TRESemmé's Botanique Nourish & Replenish Shampoo. It cleanses effectively from root to tip and enlists coconut oil and coconut milk to hydrate parched strands from the inside out, while Paul Mitchell's Tea Tree Special Shampoo gently dislodges everything from product buildup to flakes, and leaves both scalp and strands feeling fresh, not frazzled.

In short, the key to using sulfates for great hair is balance. If you're a hair-product junkie (guilty) and love to slather on serums, oils, and styling lotions, then washing your hair with them twice a month works a charm to remove buildup, not to mention dead skin cells, oil, and grime. "Deep-cleansing the hair a couple of times a month is ample, depending on your hair type," Edmonds says.

So when should you definitely not reach for the sulfates? "Regular use of sulfates doesn't work well with keratin treatments, as they contribute to the breaking down of the chemicals within said treatment," says Mark Woolley, celebrity hairdresser and founder of Electric Hairdressing. "In short, this can undo the effects of the treatment, so I would always recommend following any services with the recommended aftercare routine — you can still remove just as much dirt and excess oil from the hair with a sulfate-free shampoo. Overall, though, I’d say that sulfates are safe to use and they can provide good results, but over time can be damaging to treated hair."

But believe it or not, the same might not apply to colored hair. "There is a lack of scientific proof that sulfates are bad for colored hair," Ruggiero says. "The key to prolonging color and reducing color fade is using products that are designed to lock the color in, give protection (including products that block UV), and add both moisture and protein to keep it in tip-top condition. The better your hair condition, the better your color will be." Not too scary now, are they?