Turn Down the Heat
Good news: You don't have to completely swear off blow-drying. Just do it right. "Your hair will be much better off if you start blow-drying when it isn't dripping wet," says Boston dermatologist Ranella Hirsch. Blot, don't rub, wet hair with a microfibre which is less damaging than the classic terry-cloth turban. Use a heat-protective spray or serum.
Hairstylists love to say you can reduce the times you shampoo to three times a week. But if you have fine and/or oily hair, you don't have to walk around looking dirty. Shampoo daily, but thoroughly drench your hair with water before you lather up.Then concentrate on just the hair two inches closest to the scalp, since that's where sebum collects. And rinse really, really well under the coldest water you can stand. (Bonus: This will smooth the cuticle so frayed ends are less obvious.) Stock your shower with products that have the words "anti-breakage, "strengthening," or "renewal" on the label to thicken hair and seal split ends.
Semipermanent or permanent dyes—and not just the blonde kind—contain some peroxide, which will break down the waxy protective layer of hair, says . So just give your ends a rest. Apply dye only to the roots and then comb it through the ends in just the last few minutes. Then keep your hair looking fresh longer by using a shampoo and conditioner formulated for dyed hair.
Stretching your hair with a brush while you incinerate it with a blow-dryer is not so hot for your hair's health. But you can fight frizz less harshly. A good-quality blow-dryer, dries so quickly that there really isn't time for the hair to overheat. Ditch the big round brush for one with smooth, synthetic bristles. And at least try two things: Don't yank too hard on the hair and keep the nozzle as far away as possible. Two inches would be acceptable .
Straighten Extremely Gently
Repeat after me and your hair will thank you: I will not overexpose my hair to the flatiron. Read the manufacturers' instructions and don't exceed the maximum suggested time. (It's typically about five seconds.) Using a flatiron only once a week and swearing off all but irons with ceramic plates, , helps further. Fans of chemical straightening should consider switching to a keratin treatment, which adds a smooth coating to each strand but doesn't mess with the cortex. (Liquid Keratin 30 Day Straight is a good at-home version.) Just steer clear of anything called "Brazilian straightening"; the treatment may contain dangerous levels of formaldehyde.
Mend Your Ends
If you have the time and money to hit the salon every four weeks, great. Eveyone else? Just get a good deep conditioner. The ingredients aren't that different from those in your daily conditioner, but they're much more concentrated and they leave behind a smoothing film that won't wash off for days. Deep conditioning overnight once a week if the damage is severe—just make sure you place a towel over your pillow.