Photo: Peter Rosa

How Well Do You Know Your Hair?
You've been together forever—but are you giving your particular type of hair the very best care?

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Photo: Peter Rosa

Myth: You should always shampoo before conditioning.

Fact: If you're like most people, you've always shampooed first. But there are advantages to reversing the age-old routine, especially if you have fine hair. To add softness and shine, conditioners leave behind oils, silicones, or polymers, which can be too heavy for fine strands. But if you apply conditioner first and leave it in your hair for five to ten minutes, the conditioning agents penetrate the strands and coat the cuticle, protecting hair from any harsh cleansers in your shampoo, says Wilson. Then, as you rinse post-shampoo, residual conditioner is washed away, helping to keep hair from falling flat.

Myth: If your hair tends to look oily, you should cut back on shampooing.

Fact: Washing less frequently has no effect on the amount of oil produced by the scalp's sebaceous glands; that's a matter of genetics and hormones, says Fusco. In fact, by allowing oil and dead skin cells to accumulate, you could develop a scalp condition, like dandruff.

Myth: You should avoid any product formulated with silicones.

Fact: Silicones add a thin coating to hair, which keeps out frizz-inducing moisture and smooths the cuticle so styling products and treatments can be distributed evenly and hair can be combed easily. But not all silicones are created equal: Heavier ones, like phenyl trimethicone and dimethicone, can make fine hair limp and lifeless, says Wilson; instead, use a product formulated with amodimethicone or cyclomethicone, both of which can leave hair silky without weighing it down.

Color Commentary: If you're the fine-haired type, you may be a daily shampooer—but hold off on the day you plan to dye. Hair that's squeaky-clean (or too dirty) may color unevenly, so it's best to shampoo the night before, says Hill. Bonus: Next day, the sebum on the scalp and hair shaft may help prevent irritation.

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Photo: Peter Rosa

Myth: If you have curly hair, you should skip shampoo.

Fact Chances are, you use a cocktail of creams, oils, gels, and mousses to keep your curls in check. Over time, those products create buildup, which causes further stress on your already fragile strands and can lead to breakage, says cosmetic chemist Ni'Kita Wilson. Even if dryness is a concern, shampoo at least once a week using a moisturizing formula to remove residue without stripping. Bonus: When you eliminate buildup, your styling products may be more effective.

Myth: Curly hair grows more slowly than straight hair.

Fact: Hair grows at an average rate of about a half inch per month, regardless of your texture. But because curly hair bends and curves, that added length is less noticeable. Moreover, the more curls you have, the weaker your hair tends to be, says Wilson. So if you're not taking proper care of it—using a moisturizing shampoo, conditioner, mask, and leave-in treatment once or twice a week—your hair may be breaking at the same rate it's growing.

Color Commentary: When fighting frizzy curls, conditioner is your best friend, but don't overdo it if you want your color to last. Many women load up on masks and deep conditioning treatments to combat the damage caused by dyeing—but conditioning too frequently (more often than what's listed on the product's label) or for a longer period than recommended may leach the color molecules from your hair, causing your new shade to fade, says Kari Hill, L'Oréal Paris celebrity haircolorist.

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Photo: Peter Rosa

Myth: For healthy hair, you should brush vigorously every night to distribute oils.

Fact: Brushing will indeed disperse some oil and sebum along the hair shaft, increasing shine. But don't be too zealous: Brushing also causes friction, which can lead to cuticle damage, breakage, and increased frizziness, says Francesca Fusco, MD, assistant clinical professor of dermatology at the Icahn School of Medicine at Mount Sinai.

Myth: A cold-water rinse closes the cuticle, leaving your hair frizz-free and shiny.

Fact: Water temperature won't make your hair cuticle close or open. But if your strands seem smoother and shinier after an icy rinse, you may not be imagining it. When you use cold water, you're likelier to leave behind more of the oils or silicones from your conditioner, so your hair may appear sleeker and more luminous, says Wilson.

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Photo: Peter Rosa

Myth: You don't need to wash your hair if it's in a protective style, like braids or a weave.

Fact: A braid or a weave is a great option when you don't want to deal with managing your coily hair every day, but that doesn't mean you can skip cleansing entirely. Not only can bacteria build up—potentially leading to dandruff and other scalp conditions—but also your natural hair can dry out. That would be particularly damaging since protective styles can stress it, says Wilson. To keep your hair moisturized, use shampoo and conditioner (you may want to dilute the formulas with water so they rinse out easily) or a co-wash at least once a week.

Myth: Split ends can be repaired with products.

Fact: Once hair is damaged, it can't repair itself. Split-end menders and treatments—formulated with Band-Aid-like polymers—can hold your frayed ends together, but the effect usually lasts only until your next shampoo. The only permanent solution for split ends is to cut them off.

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