From regular colouring and harsh weather to relying heavily on heated styling tools, there are many reasons why your hair might be dry, damaged, and frizzy. But according to experts, the way you wash your hair has an effect on its appearance and manageability, too.
"Every time you wash your hair, even if you haven’t dyed it, there is always a process of damage taking place," says Peter Bailey, Unilever's global technical manager. "When we look at a dry hair fibre, the cuticle edges are all flat, but in water, this fibre swells by about 30%." With normal hair, it’s not that big of a deal — but when your hair is coloured or chemically straightened, that's when it becomes an issue. "The protein can escape and create holes in the hair, which is what causes it to break," Bailey says.
As well as breakage, this damage manifests itself in split ends, fluffiness, and rapid colour fade. You might already be on board with hot-oil remedies and shine treatments, but according to Bailey, your humble hair serum has one off-label use you're missing out on: the ability to protect and repair when used on dry hair pre-shampoo.
"Hair serum is usually seen as a finishing product, but it works well when applied before you wash your hair," Bailey says. He recommends putting a few drops in your hands before rubbing them together and simply running it through the lengths of your hair. "Some of the product will come out in the wash, but a lot of it doesn’t, and what isn't washed away stays within the cracks and smooths the hair surface," Bailey says. "This adds a level of protection to the hair when you’re washing. I liken the hair strand to a scratched table: When you’re repairing it, you pile on the polish, but you remove 99% of it, and what’s left plugs the gaps and leaves you with a nice polished surface."
Unlike the process of applying a conditioner before shampoo, an initial rinse isn't required when using a serum, so hair spends less time in water and therefore is less likely to swell and end up prone to damage. Whether you want to follow with a conditioner or a hair mask is up to you. "Applying serum before shampooing is especially useful if you’re worried about making your hair greasy after washing," Bailey says.
To prevent further in-shower damage, Bailey suggests opting for a shampoo with a mild surfactant system. This doesn't mean sulfate-free, necessarily — just less lather. Interestingly, Bailey doesn't buy into the idea that sulfates are inherently bad. "You’ll cause less swelling to the fibre if you have a milder system. Contrary to popular belief, gentle cleansers will take the grease off the surface," Bailey says. "This isn’t so important when your hair is untreated, but if it is keratin straightened or coloured, you've actually damaged the internal structure of the hair fibre." So opting for kinder shampoos can protect and prolong both colour and treatments.
It's also super important to towel dry as gently as possible. "As you towel dry, you’re chipping off the cuticle," Bailey explains. "When hair is coloured, this is multiplied tenfold and it’s much more likely to cause damage. You’re not going to avoid washing your hair, as it’ll become dirty, but it’s all about going through the process in a gentle, caring way." Using a hair-specific towel, like the ones from Aquis, will absorb water and keep frizz on lockdown.
And if your hair is curly, take hairstylist Larry King's advice and try not to touch it when drying. "The moment you start touching it is when it goes frizzy," King says. Simply tip your head upside down and let your hair fall into your diffuser of choice. His simple suggestion? "Put one hand in your pocket and let the diffuser do everything."
At Refinery29, we’re here to help you navigate this overwhelming world of stuff. All of our market picks are independently selected and curated by the editorial team. If you buy something we link to on our site, Refinery29 may earn commission. This story was originally published on Refinery29 UK.