When your best friend boasts that she stopped washing her hair three weeks ago and “it’s never looked better,” it’s hard not to cringe and take a step back.But surprisingly, the “no ‘poo” movement is a growing trend that has celebrities and hair stylists alike jumping on the shampoo-shunning bandwagon.The most unlikely people are ditching their suds—folks with oily hair. So why would anyone choose to stop shampooing their strands?

Many a hairstylist claims that if you wash your hair less often you can actually train your hair to be less greasy. The theory is based on the idea that shampoo creates a supply-and-demand relationship: It strips the hair of sebum (that oily substance that helps hydrate hair, as well as ward off bacteria and wetness). In order to compensate, our scalps produce too much of the stuff, which in turn creates the grimy, greasy hair look.The “no ‘poo” movement claims that, in order to get hair back to its purest, most stunning state, you have to wean your locks off the sudsy stuff. This often proves to be a painful process—particularly for the fine-haired flock—complete with itchy scalps, vinegar rinses, obsessive hair brushing and slick-looking strands.

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But is all that suffering for the greater good of your hair? We checked in with some hair and scalp specialists who revealed that it’s more hairsay than reality.“Your scalp produces oils at a constant rate, regardless of how often you wash your hair,” says Pantene Senior Scientist Jeni Thomas.

Fine hair generally gets oilier quicker since there’s simply more of it—its small diameter means you’ve got more strands hanging out on your head. And since each hair follicle produces oil, the more hair you have, the more oil you crank out.Liz Cunnane, a tricologist at the Philip Kingsley Clinic in New York City, has done extensive research on the topic at their New York and London clinics. In her studies, she found that healthy hair is a result of a healthy —and clean—scalp. “Fine hair will always look better when it is freshly washed,” she says. “It will always have more body and movement when clean.”

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But what if you have a thick or more textured hair type? “You will not need to shampoo daily, but you must remember that the process of shampooing and conditioning is important because it reintroduces moisture to the hair,” says Cunnane.Even though you can’t fool Mother Nature when it comes to taming your mane’s oil production, there are some tricks of the trade to keep limp, greasy locks at bay. Cunnane suggests using a shampoo that gently cleanses and adds body and contains certain ingredients, such as copolymer (for surface volume and aid in controlling flyaways), natural cellulose (to thicken texture) and keratin protein (to strengthen and improve fullness). Also, overusing styling products will weigh locks down, along with unnecessary hair handling, which transfers oils from your fingertips to your hair.

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