Val Monroe
Q. I have thick, dry, curly hair. Am I better off skipping shampoo, as I've heard some people are doing?

A: Though shampooing less frequently is okay if your hair is very dry, it's not a good idea to skip it altogether, says David Kingsley, PhD, a New York City trichologist (hair expert). Shampooing is the most efficient way to remove oil and dirt from the scalp. If you wet your hair more than once a week, wash it just once and use a conditioner the rest of the time. If you wet your hair only once a week, wash it then and use a leave-in conditioner (like L'Oréal EverSleek Humidity Defying Leave-In Creme, $9, drugstores) or a moisturizing, antifrizz conditioner (like Tresemmé Climate Control Conditioner, $5, drugstores).

Keep in mind: When styling, use a gel or antifrizz cream and then don't touch your curls, says Rita Hazan, colorist and owner of the Rita Hazan Salon in New York City. The more you fuss and play with your hair, the frizzier it will be.

Q: C'mon. Do I really need sunscreen for my hair?

I was similarly skeptical when I first noticed hair products containing sunscreens. But the sun's UV rays can damage hair, especially if it has been colored or overprocessed by straightening or heat styling. The UV rays weaken and break the protein bonds in the hair shaft and can also fade color, says trichologist (hair expert) David Kingsley, PhD. The sun's heat can weaken the strand's outer layer, drying it out and making it look rough and frizzy.

So yes, it's a good idea to protect your hair. You can try a product formulated for that purpose (like Fekkai Beachcomber Leave-in Conditioner, $24; drugstores). Or you could slick back your hair with a mask or conditioner while you're at the pool or the beach.

Keep in mind: A wide-brimmed hat will not only save your hair but also shield your face from damaging UV rays.

Q: How often should I brush my hair? And what kind of brush is best? 

A: In spite of the old biceps-building 100-strokes-per-night advice, you should brush your hair minimally. Routine brushing damages the outer layer, or cuticle, of the strands, which can make hair look lusterless and frizzy, says Paradi Mirmirani, MD, assistant professor of dermatology at the University of California, San Francisco; better to use a comb with widely spaced teeth and smooth tips. But if you like the way a good brushing feels (as I do), avoid boar bristles, which generate damaging friction; instead, choose a model with plastic, ball-tipped bristles. The Goody Ouchless Cushion Brush ($7.99; drugstores) is a fine choice.

Q: Is it good to brush my hair vigorously? 

A: Funny you should ask. A stylist recently told me, after giving me what might generously be called an "energetic" shampoo, that since I have my hair washed in a salon only every five days or so, I should brush it hard daily "to distribute the oils on your scalp." (She also told me, with obvious concern, that my scalp felt "tight," which got me wondering about how loose my scalp should be. Not very, I decided.) But Philip Kingsley, a New York City and London trichologist (hair specialist), says, "It's definitely bad to brush your hair vigorously, ever. Hard brushing tends to scratch the scalp and will also tear out the hair and break it, particularly if it's long." It's fine to use a brush for styling purposes, he says, but not to distribute oils, because who wants oily hair? Dry hair is due to loss of moisture, not oil. Kingsley suggests using a conditioner after shampooing. And when you do use a brush, look for one with plastic, malleable bristles on a rubber base with vents. Ball tips on the bristles help prevent breakage, Kingsley says.

Bottom line: The less you brush your hair, the better.

Q: My hair keeps breaking; how can I prevent split ends? 

A: This is one of those questions I'm asked with startling regularity—like three times a day. And I think there's a good reason: Unless you're a haircare zealot—by which I mean you see your stylist without fail every six weeks for a trim, you never overshampoo or overstyle with heated tools, and you wouldn't go near a chemical treatment—some breakage and split ends are inevitable. But a few suggestions from master stylist Barry Reitman at Kevin Josephson Salon in Beverly Hills can help:
  • Use a moisturizing shampoo and rinse-out conditioner, concentrating the product on your split ends.
  • Rinse with cool water to seal the hair's outer layer.
  • Detangle with a wide-tooth comb.
  • Pour a bit of shine serum into your palm and glide it over split ends.
  • Be sure to dry your hair thoroughly; split ends look worse when they're frizzy.
  • To camouflage the ends, apply a light heat protectant when hair is completely dry. Then use a ceramic or Teflon flatiron to straighten the bottom inch of your hair.
Bottom line: Because of normal wear and tear, you can't prevent split ends entirely. But they can lead to breakage higher up on the hair shaft, so getting regular trims is important to your hair's health, says Antonio Prieto, of Antonio Prieto Salon in New York City.

Keep reading: What to do about broken hairs