You may be washing your hair more often than you need to.

"I hear so many people obsess about shampooing their hair every day," says Nick Arrojo, owner of New York's Arrojo Studio and former stylist on TLC's reality makeover show What Not to Wear. "They get freaked out because they think anything less will result in dirty, smelly hair. But shampooing three or four times a week is plenty."

Ultimately, how often you shampoo is a matter of personal preference. "It really depends on the scalp and hair type and what you do to the hair," says Paradi Mirmirani, MD, a Vallejo, Calif., dermatologist and specialist in hair research.

Chances are you can stand to lather up a little less.

Shampoo Daily?

Dermatologists and stylists agree that there's little reason to shampoo every day.

"Hair is a fiber," Mirmirani says. "Think of a wool fiber: The more you wash it, the worse it's going to look. There's no need to wash your hair every day either."

The longer, thicker, curlier, and more processed your hair, the longer it can go between washes.

"This is because the oils from the scalp do not travel down the hair shaft as quickly, so the hair tends to be dry and requires less frequent shampooing," says Heather Woolery-Lloyd, MD, director of ethnic skin care at the University of Miami.  

Even most unprocessed, short, thin, straight hair can skip a day.

Daily shampooing is only necessary if oil production on the scalp is high, Zoe Draelos, MD, writes in the International Journal of Trichology.

Arrojo says that the only reason to shampoo daily would be for the fragrance. And if you must, he says, you should use a lightweight shampoo.

Lightweight shampoos, also labeled "everyday shampoos," contain milder detergents than others.

Every Few Days?

Laura Saunders, a stay-at-home mom in Raleigh, N.C., has straight hair. "It gets oily fast," she says. "I only wash it every other day, and I put some baby powder on it if I need to absorb some of the oil on the other days," she says.

Arrojo says that powders and dry shampoos do work for absorbing oils between washes. "One trick is to use talcum powder in the hair in lieu of shampoo," he says. 

The powders shouldn't replace shampoo all together, Woolery-Lloyd says.

Many women shampoo their hair less often than Saunders. Melissa Capasso, an artist in Brooklyn, N.Y., shampoos her long, thick curls once a week. "If I shampoo more than that, my hair dries out, it loses its natural curl, and it gets frizzy and unmanageable."

Capasso relies on daily conditioning and scalp massage to break up oils, loosen dirt, and keep her hair manageable between shampoos. And try not to leave your hair wet for  a long time and use a http://www.the-best-hair-dryer-reviews.com - hair dryer to dry it fast.