10 ways you're ruining your hair

10 ways you're ruining your hair
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10 ways you're ruining your hair
Hairstylists are forever telling us to lather up less frequently for healthier, shinier hair. But don't get too cozy with your dry shampoo—product buildup attracts dirt and weighs down hair, leaving it dull and weak. Washing your hair two or three times a week strips away layers of product and excess oil. Use a clarifying formula once a month. It cuts through grease that gentler sulfate-free shampoos can miss and leaves hair primed to soak up the smoothing ingredients in your conditioner.
Hair is at its weakest and most elastic when it's really wet. The tight pull of a brush—especially a natural-bristle one—can overstretch the hair shaft and lead to breakage, says cosmetic chemist Joseph J. Cincotta. A better detangling strategy: Use your fingers or a wide-tooth comb to work through knots while your hair is coated with conditioner in the shower.
Remember that last slide? You shouldn't be brushing superwet hair. Plus, the sooner you start blow-drying, the longer your hair is exposed to damaging heat. Start your blowout when your hair has already air-dried at least 50 percent of the way. And you know what? The final result will be exactly the same. "You hair's pattern is set when you're taking it from just slightly damp to dry," says Jeni Thomas, a principal scientist at Pantene. She recommends squeezing out excess moisture with a towel (microfiber ones minimize friction—and frizz) and then letting hair air-dry as much as possible—up to 90 percent—before finishing with a brush and blow-dryer.

Natural-bristle brushes are great for grabbing thick, slightly damp hair and smoothing it out during a blowout. But they create too much tension on fine or damaged hair. Vent brushes are a gentler option. Their rubber-tipped bristles glide through the hair, and they have open backs that allow air and moisture to pass through for a quicker blow-dry (remember, less time means less damage).

TIP: Check comb teeth for seams or roughness (there shouldn't be any) and run your brush along the inside of your arm. If there are any scratches, toss it. If it harms your skin, it's going to harm your hair, too.

One more time: Heat damages your hair. We're not suggesting you swear off it completely, but you need to keep temperatures in check. "If your blow-dryer hurts your scalp, it's too hot," says Thomas. Your best bet is to use one with at least 2000 watts and set it on medium heat. That way, you're relying more on airflow than on heat to eliminate moisture. And never, ever turn your flatiron above 350 degrees.
Yanking of any kind doesn't do your hair any favors, but it's especially damaging when the weapon of choice is a flatiron. "The combination of heat and a pulling action can really weaken your hair," says Thomas. So go easy with your iron. And always, always use a heat-protecting styler first. Most contain some combination of silicones, cetyl alcohol, and quaterniums, all of which help the iron glide along the hair shaft without tugging. 
When it comes to putting that final gloss on your hair, a silicone is not a silicone is not a silicone. The ones found in spray formulas (they usually have a "cyclo" prefix) can dry out hair over time, says cosmetic chemist Ni'Kita Wilson. Serums that contain dimethicone or phenyl trimethicone are a safer bet. Just remember that using any kind of hair serum or oil (many of which contain more silicones than actual oils) is a bit like happy hour: Get too enthusiastic and you'll have a big, sloppy mess on your hands. Comb a drop—and only a drop—through damp hair before drying and styling as usual. And as long as you shampoo a few times a week, don't worry about silicone buildup. It rinses right out.
We're not mandating extension abstinence, but an occasional detox could mean the difference between bald patches and full, healthy hair. Weaves sew tracks to tight braids, which tug at the hairline, and lace-front wigs act almost like epilators, yanking out the hair, says Wilson. "That's when you see traction alopecia, where the hairline recedes from tight pulling." Clip-in pieces are the most gentle option; they're very temporary and very easy to remove. Glue-in extensions last a few days, and tape-in varieties stay put for several weeks; both cause minimal damage if they're taken out properly (and professionally). But if you're a die-hard sew-in fan, Wilson recommends wearing extensions for a maximum of eight weeks and taking at least a two-week break in between.
You should be able to go about four to six weeks between dye jobs. If you find yourself needing more frequent color upkeep—which can stress and damage hair—make a few changes at home: First, avoid styling products with alcohol, since they strip away dye and expedite fading. Put a filter on your showerhead to prevent chlorine and minerals from breaking down color, and always use a shampoo and conditioner formulated for color-treated hair.
Just like the peroxide in permanent hair color, relaxers are chemicals that can destroy the hair if they're not applied properly. "A relaxer should be done by a professional every four to eight weeks, depending on your hair growth," says hairstylist Ursula Stephen. "And when you go back for a touch-up, the solution should be applied only to the new growth." Some stylists pull it through the whole strand, which leads to dryness and, eventually, breakage.

When all the shea butter and coconut oil in the world can't revive your broken (or frizzy or dull or...) hair, it's time to start playing some damage-control offense. Here are the ten hair-trashing habits you need to quit cold turkey.

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