Why You Should Treat Your Scalp to a Detox

You've heard it hundreds of times: Extending time between shampoos (and making do with dry shampoo) preserves your color, lets your scalp's natural oils hydrate the hair, and minimizes heat-styling damage. Problem is, what's good for your hair isn't necessarily good for your scalp, and an unhealthy scalp eventually affects the quality of new hair growth. "I've seen a steady uptick in patients who come in complaining of chronic scalp irritation, hair breakage, and shedding-issues largely rooted in underwashing and overusing styling products," says Shereene Idriss, M.D., a dermatologist at Union Square Laser Dermatology in New York City. So how you do reconcile the needs of your hair with the care of your scalp? It's not that hard. Start by following our regimen here.

Step 1: Keep it Clean.

You wouldn't go for days without washing your body, then sprinkle powder on your forearm and consider it clean," says Shani Francis, M.D., a medical director at Ashira Dermatology, who says calling dry shampoo shampoo is a misnomer. To keep your scalp healthy, you must treat it as you do your facial skin and remove impurities regularly-as in every three days at a minimum. "Styling products should not be left on your scalp for days and days," Dr. Francis says. If they are, the scalp skin will become irritated, preexisting conditions like psoriasis, eczema, and dandruff will flare up, and you will impede hair growth. David Adams, an Aveda colorist and the owner of Fourteenjay Salon in New York City, describes it like this:

"When you don't shampoo regularly, product buildup becomes so dense, it blocks the opening of hair follicles, limiting the number of strands that can get out. This means a follicle that was once growing three or four strands may now sprout only one or two."

Step 2: Slough the Dead Stuff.

"Removing dead-skin cells from the scalp improves the health of your epidermis, stimulates hair follicles, and promotes more robust hair growth," Dr. Idriss says. Gentle sloughing also gets rid of stubborn sticky or oily product buildup that may not be completely broken down by shampoo or even a clarifying formula. "If your hair and scalp are in good condition, exfoliating once or twice a month is plenty," Adams says. But if your scalp is flaky or itchy-or you've been going long stretches without shampooing-up the ante to weekly exfoliation for the first month.

As for shedding methods, the simplest one is to just "manually exfoliate the scalp skin using a brush with soft rubber tips," says Temur Dzidziguri, a stylist at Sharon Dorram Color at Sally Hershberger Salon in New York. Massage the scalp with the bristles to loosen dead skin and grime, then step into the shower and shampoo it out. Another option: Add a teaspoon of sugar to a quarter-size drop of shampoo to make your own cleansing scrub.

Step 3: Drink Up.

"Just like the skin on the rest of your body, the scalp needs moisture to function efficiently," Dr. Francis says. But lubing up daily like you do on your face or hands is impractical and unnecessary. Hydrating once or twice a week should suffice, says Dr. Idriss, who says you can simply massage a little conditioner into the scalp, postshampoo, while you condition your hair. There are also easily absorbed leave-in scalp serums and tonics that can be applied right after shampooing to hydrate and rebalance the scalp.

Step 4: Use Protection.

Shielding the scalp from UV rays whenever possible is key, says Dr. Idriss, who adds that UV-related actinic keratosis damage to the scalp can cause hair loss-and lead to skin cancer. Consider using a powder sunscreen on areas where the scalp is exposed or, if you are at the pool or beach, treating an oily sunscreen as a scalp protectant and styler-after spritzing it on, slick hair into a chignon.