oil, dried sweat, dirt and dead skin cells, says Dr. Robert Dorin, a board-certified hair transplantation surgeon in New York City.
Those using “no-poo” products “aren’t really cleaning their scalp,” he says. “They’re not taking off the environmental impurities.”
People who don’t use detergent shampoo to clean the scalp run the risk of developing fungal and bacterial infections, Dorin shares.
They also might suffer from irritation of the scalp, flaking and pimple-like lesions, Donofrio says.
Regular shampooing also helps control and treat scalp problems, such as psoriasis, eczema and dandruff, according to Lamb.
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How often should you wash your hair?
Still, there’s no hard-and-fast rule for how often to wash your hair with a detergent shampoo, the dermatologists agree.
Lamb says that everyone is different, and the only way to know how often you should wash your hair is to experiment.
“You’re not putting your hair at risk by trying this,” she adds. “Try it and see. Frankly, I have some patients who love it, and say their hair is the healthiest it’s ever been. And I have other patients who say their hair has too much build-up; their scalp is too oily; their scalp is itching.”
Donofrio agrees. “Bottom line: if you feel the need to join the no-shampoo movement, your hair will tell you if it works for you.”