Plus, an expert explains whether you really need to make the switch.

By Roberta Schroeder

Much has been made about the use of sulphates in haircare products. Like so many traditionally common ingredients before them – think preservatives, fragrance, parabens and silicones – sulphates are now at the centre of a debate, fuelled by our increasing interest in a gentler, ‘cleaner’ beauty routine.

But do sulphates really need to be stripped from your bathroom shelf? Here, we explain everything you really need to know about these much-discussed cleansing agents, and reveal the best SLS-free shampoos on the shelves right now, should you wish to try one.

What are sulphates?

“Sulphates are chemicals that work as foaming agents within most shampoos,” explains hair stylist Paul Edmonds. “They break down oil and dirt so that the hair can be cleansed properly.”

However, not all sulphates are equal. Sodium lauryl sulphate and sodium laureth sulphate are the most widely used sulphates in haircare, and they’re also considered to be the harshest. Now, gentler alternatives are on offer, including ammonium lauryl sulphate and the coconut-derived sodium coco-sulphate.

Is sulphate-free always better?

Sulphates, like preservative parabens, are not inherently bad things – both have been used in cosmetic products for years. For example, sulphates are probably behind the foam in your favourite bubble bath, as well as in your toothpaste and laundry detergent. Haircare is an area of the beauty industry fraught with scaremongering, and it pays to take any ‘clean’ claims with a pinch of salt.

“Not all sulphates are bad: not even all of the ones that get a bad rap,” confirms Edmonds. “Sulphates are perceived as being very harsh, but if you use a good quality shampoo, it will undoubtedly include other ingredients that help stop the negative impacts of sulphates. It then doesn’t damage the hair, but simply opens up the cuticle and draws out the grease.”

However, there are some hair types that will benefit from skipping the sulphates. Some SLS-heavy formulas can be drying to both the scalp and hair, meaning they can create frizz in curly hair. If you’re looking to encourage springier curls, it might be worth going sulphate-free (or even investing in a creamy co-wash).

Furthermore, those with especially sensitive skin might find a sulphate-rich shampoo irritating. And finally, those with colour or keratin-treated hair should also skip the harsh sulphates, as they can degrade both colour and straightening treatments.

On the contrary, other hair types are best treated with a (good quality) sulphate-based shampoo. “Fine hair requires the deep cleanse that sulphates provide in order to build body,” says Edmonds. What’s more, if you use a lot of styling products and notice residue lingering in your roots, sulphates remain the best route to satisfyingly clean hair. If you’re curious about the benefits a sulphate-free shampoo could bring you, try one of the Bazaar team’s top picks below…