What do you have to do to get thicker, shinier, healthier hair? For a growing group of people, the answer is simple: Do nothing. As in, don't wash it.

Celebs like Robert Pattinson, Jessica Simpson, Prince Harry, and certain hair gurus have stopped washing their hair entirely. "Though it seems harmless, shampoo strips hair of sebum, which is essential for healthy locks," says Bianca Arussi, co-owner of J'Adore Salon Beverly Hills. "To compensate, your scalp overproduces sebum, which leads you to lather up more often to counteract this oiliness. You are now stuck in a vicious cycle of over-washing, making hair greasier and drying out ends."

Experts say that after about six weeks of no-shampooing (you can wet your hair, blow dry it, and do things like rinse with vinegar and weekly baking soda scalp rubs to get sweat and stink out), you'll see thicker, healthier strands. "The goal is to wash your hair no more than three times per week," Arussi says. "That will set you on the path to healthier, more low-maintenance hair."

We asked Arussi for her tips on how to shampooing less:
  • Begin by going a full week without washing.
  • When you do shampoo, use a gentle, sulfate-free formula that won't harm hair's color or texture.
  • Apply conditioner to ends only. Your scalp will take care of the roots and mid-shaft.
  • Use dry shampoo in between washes to add texture and soak up excess oil. Arussi recommends Giovanni Powder Power Dry Shampoo.
  • Try a textured style-like braids-to conceal greasy roots on no-wash days.
  • Skip slick formulations like shine serums that can weigh hair down.
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