Like wrinkle-free skin, silky hair is something you take for granted in your teen years. But sometime in your 30s, you may begin to notice that your hair isn’t its usual youthful self. Unruly gray strands start infiltrating like a gang of graffiti artists, and your once-bouncy locks become ragged, fried and limp, no longer responsive to your regular styling products.

Don’t despair. Scientists are studying how hair changes as we age, examining both how hair is influenced by outside factors (like sunlight and heat styling) as well as internal factors (like hormonal changes) that may affect shine and texture. As a result, says Steven Shiel, a Pantene hair care expert who holds a doctorate in organometallic chemistry, a battery of anti-aging grooming techniques and products has emerged to help our hair retain its luster, fullness and bounce.

Here’s how to keep your hair looking its finest, whether you’re 24, 34, 44 or 64.

Revive Youthful Shine
Years of sun exposure, chemical processing and heated styling tools fray the hair’s cuticle and create an uneven surface that absorbs light. What’s more, your body’s natural shine-enhancing oils become less plentiful in your 30s and beyond. “As you age, the production of sebum decreases,” says Shiel. “That means a drier scalp and hair.”

Restore luster with a regimen that includes a conditioner every time you shampoo; look for the ingredient cetyl alcohol, to retain moisture, and dimethicone, to add sheen. Use a deep-conditioning treatment once a week. And for an instant radiance boost, make a shine-enhancing finishing spray the last step in your styling routine.

Create More Volume
While men watch their hairlines recede and scalps go bald, women experience more of an all-over thinning as each hair fiber shrinks in diameter through the decades. You might notice, for example, that it takes another twist of an elastic to hold your ponytail in place.

The texture of your hair also changes. “As hair strands shrink, they can become fine and limp,” says Shiel, “and they’re likely to go flat if your shampoo or conditioner is too heavy.”  Products that are custom-designed for fine hair contain cleansing ingredients that gently remove the accumulated scalp oils, dirt and styling residue that can cause hair to droop.

If you crave more voluminous locks, then mousse should be in your styling repertory, suggests hair expert John Gray, author of The World of Hair. Mousse contains the greatest concentration of cationic polymers, compounds that Gray calls “magic bullets” when it comes to fattening up skinny strands.

Coloring your hair, believe it or not, can actually make fine locks look thicker, healthier and more dimensional. That’s because dyes lift the cuticle, thickening individual hair fibers. Highlights lead to even greater swelling of the strand by creating a contrast of light and dark tones.

Baby Chemically Processed Locks
Helpful as color is in making hair appear fuller, you’re not only changing your hair’s hue when you dye or highlight it -- you’re also changing its structure. Color-treated hair becomes more negatively charged, making it rough, dull and more vulnerable to damage. The first line of defense is using your hot styling tools with caution. Apply a heat-protecting product before you blow-dry or flat-iron your hair. Set these tools on the lowest temperature that will help you achieve the styling you want without burning your locks.

The second line of defense is to use shampoos and conditioners that are formulated for color-treated hair. These contain UV filters that protect your hair against the sun’s rays -- which can fade color and turn highlights brassy -- and moisturizing ingredients that replenish and refine roughed-up cuticles.

In winter, the combination of indoor central heating with weather that’s bitter cold or soggy wet can turn hair into a frizzy, brittle mess of static, or a dull, limp mop immune to your styling attempts. And that’s on the good days.

Winter hair is so universally vexing that international teams of scientists have studied how hair reacts to varieties of winter weather, indoors and out. In laboratories and in salons, experts are learning how to formulate helpful products and alter styling and grooming routines to counteract cold-weather extremes.

What these pros have discovered is that hair that’s been chemically treated becomes particularly vulnerable to changes in humidity and temperature. According to expert John Gray, author of The World of Hair, your tresses have a built-in conditioning system called the f-layer. This microscopic coating is like a good pair of ski pants for your hair: It makes the strands naturally water-repellent, smooth and silky. Dyes and straightening treatments, however, remove that protective coating.

 “Once that happens,” says Gray, “the ability to control hair’s water content, which is critical to the way hair looks and behaves, is grossly affected.” As a result, a day of snow or rain can make your hair heavy and unmanageable.

Don’t panic: Even damaged hair can regain its youthful luster with the right handling.

Tweak the Way You Shampoo
Hair needs sufficient interior moisture to counteract winter’s dry indoor air and to protect it against cold or humidity outside. Charles Ifergan, a stylist and salon owner in Chicago -- a city with one of the harshest winters in the country -- suggests using a slightly lesser amount of shampoo from December through March to avoid stripping hair of natural oils. “And don’t rinse out the conditioner as hard. It’s OK to leave a little bit in for extra moisture,” he says.

Dial Down the Hair Dryer
When it’s freezing outside, it’s tempting to blast your soaking-wet hair with your blow-dryer on its hottest setting, if only to warm up the bathroom. That’s a fast route to damage. “You basically end up boiling the water inside your hair,” says Gray. Instead, towel-dry your hair, then give it time to dry on its own. When it’s just slightly damp, apply heat-protecting styling products and use your blow-dryer on a medium to low setting.

Don’t Make Hat Hair Worse
Smashing hair under hats and scarves not only flattens your locks, but the trapped heat can cause the scalp to perspire, making the roots feel unclean, says Gray. That flat, greasy hair often leads to more frequent washing and heat styling. Hat hair may be unavoidable, but you can prevent further damage to the exposed dry ends by brushing them gently and making them the first place where you apply conditioner. 

Step up Your Conditioning Routine
“Every couple of weeks, use an intensive conditioning mask,” says Ifergan. And, after you blow-dry you hair, rub a tiny amount of conditioning oil between your palms, then apply it lightly to your hair as a finishing product.

Stop Static
Ultra-dry, cold weather and central heating can increase static electricity so much that hair becomes frizzy and style-resistant. Products with “smart” ingredients, such as polyquaternium-10 in shampoo and stearamidopropyl dimethylamine in conditioner, control static by depositing their helpful molecules only where needed, like on dry ends. Switching from a nylon or synthetic brush to one with boar bristles will also de-electrify runaway strands, says Ifergan.

Curly haired women no longer have to envy their straight-tressed sisters. Today, curly hair -- in all its beautiful textures -- is getting the attention and products it deserves to look its magnificent best.

New research is helping manufacturers develop products that address curly hair’s unique characteristics. For example, French researchers discovered that African hair is drier, slower growing, and more likely to fray at the tips and split lengthwise. Hair care scientists have also determined that the twists and turns of curly hair bend the shaft’s scalelike covering, making strands rough and difficult to control.

For hair that’s curl-luscious, follow this advice from the pros:

ID Your Curl
“Think of texture in terms of how your hair is shaped -- kinky, curly or wavy,” says Anthony Dickey, who operates a New York salon devoted to textured hair and is the author of Hair Rules!: The Ultimate Hair-Care Guide for Women with Kinky, Curly, or Wavy Hair. Kinky hair has the tightest curl pattern and is often frizzy. Curly hair has looser twists and turns, while wavy hair exhibits a softer, more open curl.

Treat Your Dominant Hair Type
You may have curly hair -- but only in a patch at the back of your head. Or maybe your kinky hair calms to a gentler curl along the sides. It’s wise to cater to your dominant type, says Domingo Serquinia, co-owner of Paint Shop, a Los Angeles hair and nail salon. If portions of your hair are curly on an otherwise tame head of hair, Serquinia recommends using a temporary straightener, such as the new keratin treatments that many salons offer. Stylists can moderate the amount of temporary straightener to add manageability to curls, not flatten them. If your hair is kinky rather than curly, skip the keratin and opt for paste-formula relaxers that can be applied precisely to new growth.

Choose a Product Line for Your Hair Type
Curly, kinky and wavy hair need extra hydration because their winding structure impedes the flow of scalp oils along the strand. Product lines formulated for curly hair, including those designed specifically for women of color, contain additional moisturizing ingredients that your thirsty tresses will drink right up.

Don’t Skip Regular Cuts
Curly hair may grow slowly, but it still needs trimming every three months to keep the ends fresh, says Serquinia. But he advises, “You don’t want your stylist to use a razor or cut into the ends, because that can fray ends and add to the frizz.”

Keep Your Curls Cool
If your hair has been processed with chemical straighteners or permanent-wave solutions, steer clear of high-heat styling tools like flatirons, suggests Miami, Fla., dermatologist Heather Woolery-Lloyd. That’s because your hair may already have blisterlike bubbles from the processing, and heat can cause those bubbles to break or split, leading to damaged, distressed locks.

Handle With Care
Because of their lower tensile strength, some types of kinky hair have decreased resistance to repeated brushing, says Woolery-Lloyd. Avoid vigorous brushing and work carefully through knots and tangles to avoid breakage. After shampooing and conditioning your hair, remove wetness with a gentle squeeze. Apply a styling product to still-wet hair to protect the cuticle and retain the hair’s natural curl.

Think Breeze, Not Blast
To get salon results at home, without having to master the tricky two-handed round brush technique, look for a blow-dryer with a wide-tooth comb attachment and use it on a medium setting. Or, suggests Dickey, use an old-school portable hood dryer that lets hair dry in place with minimal tangling. The gentler airflow of the portable dryers is less disruptive to the curl pattern than the typical blow-dryer. Bonus: Your hands will be free to apply your makeup.

Da dona de casa à executiva super poderosa, não há mulher que não se preocupe com a beleza dos cabelos. No caso das atrizes e modelos, porém, essa preocupação é redobrada. Não só elas precisam estar sempre lindas diante das lentes da TV, como, nas horas de folga, ainda precisam se sair bem nos flashes roubados pelos paparazzi. Ao mesmo tempo, seus cabelos sofrem com as exigências da profissão: são submetidos a horas de secador, mudanças radicais, tinturas freqüentes... O resultado é que poucas mulheres entendem tanto da saúde dos fios quanto elas. Por isso, fomos consultá-las. Aproveite as dicas para ter o cabelo das estrelas.

Thaissa Carvalho
“Mantenho o corte em dia e uma vez por mês faço um tratamento à base de queratina. Alterno as marcas de xampu e condicionador. Se vou à praia nunca deixo de passar protetor solar nos fios. Como estou com um corte de cabelo bem repicado para dar aquela aparência mais desconectada,  uso uma pomada em pó que dá um efeito ‘Gisele Bündchen.’”

Juliana Alves
“Um dos segredos é variar. Em relação ao xampu dou preferência aos sem sal ou hipoalergênicos e condicionadores só compro os para cabelos crespos. Nos dias em que não estou gravando posso me dar ao luxo de usar um leave in mais oleoso. No entanto quando gravo dou preferência a um tipo de leave in que segura mais o penteado. Nunca durmo com os cabelos molhados.  Antes de usar secador ou baby liss uso um protetor térmico para não danificar os fios. Toda semana faço hidratação e reconstrução. Cuido dos meus cabelos com uma profissional especializada em cabelos étnicos, a Laís Castro.”

Carol Castro
"Lavo o cabelo e deixo secar naturalmente. A cada 15 dias faço tratamento anti-aging  para evitar o desgaste dos fios com a cabeleireira Cintia Araújo, do Salão Fashion Clinic, em Ipanema, no Rio de Janeiro."

Larissa Maciel
"Por conta da minha personagem, a Felícia da novela Passione, tenho feito escova quase que diariamente. Aproveito para usar isso a meu favor e escolho produtos que tenham suas potencialidades ativadas pelo calor do secador. Assim, ao invés de agredir o cabelo com a alta temperatura, o calor ajuda a deixar o fio mais hidratado, macio e brilhante. Acho os produtos termo-ativados um recurso maravilhoso!"

Carolina Kasting
“Meus cabelos sempre foram naturalmente negros. Mas  para interpretar a Judith, minha personagem de Escrito nas Estrelas, precisei cortá-los e tingi-los de loiros. Depois da tintura, estou usando um xampu próprio para dar mais luminosidade que também deixa meus cabelos muito macios. Além disso, toda semana passo um creme de hidratação mais pesado.”

Betty Gofman
“Não abro mão da natação e como os cabelos louros ficam facilmente  esverdeados, por causa do cloro, só nado em piscinas que sejam salinizadas e que tenham a menor quantidade de química possível. Além disso, fujo de escovas e de tintura. Procuro estar sempre com um corte que fique bonito se eu deixar secar naturalmente e uso xampus que tenham pouco sal. Para mim, quanto mais naturalmente tratamos os cabelos, melhores eles ficam. Por melhor que seja o produto faço questão de ver se é testado em animais. Se for, não compro.”

Believe it or not, tackling bad hair days is an achievable feat -- and one you can even do in style and with as much flair as someone who had spent a better part of the morning primping and preening in the bathroom. These strand-smart strategies will ensure that no tress distress will put a damper on your crowning glory.

The Right Cut
Believe it or not, your daily hairstyling routine starts at the salon. “A great haircut gives you a beautiful, face-framing shape and complements your features perfectly,” says Nick Arrojo, celebrity hairstylist and author of Great Hair: Secrets to Looking Fabulous and Feeling Beautiful Every Day. “The best way to do that is to get a cut that matches the texture and shape of your hair, not the shape of your face,” he explains.

So, before you ask your hairdresser for a cut to “make your cheeks look smaller” or “forehead less wide,” focus on the inherent qualities of your tresses -- from shape (straight, wavy, curly) and texture (fine, medium, coarse) to density (heavy, medium, light) and the unique combinations of these characteristics. “Not every hairstyle suits every type of hair,” says Arrojo. “If you work with your hair in its natural state, you will achieve greater success in maintaining your style.”

To-do Updo
A neat, sleek ponytail may be the quickest way to get you out the door in minutes when your hair refuses to cooperate with any brushing or shaping. But “sleek” here is the operative word. It’s easy to tousle hair up into a half-hearted updo, rendering a haggard-looking finish. (Only models seem to get away with this and still manage to look fantastic.) If you’re doing a ponytail, go for it 100 percent. Start by brushing out all the tangles, from ends to roots. “If you start at the roots and work through the ends, you can push all the knots in your hair together into one big tangled mess,” says Arrojo. Next, dampen hair and work in a little styling gel -- or wax if you prefer a matte effect -- on palms, evenly distributing it throughout strands. Use a brush or a fine-tooth comb to neatly gather hair all around. Secure with a fabric-covered elastic, or even a bejeweled clip. Steer clear of ordinary rubber bands, as they can snag locks.

The “Yorkie”
An edgier alternative to the ponytail is the “Yorkie,” a fashion-forward updo inspired by Yorkshire puppies. The look can very well be Mohawk-inspired, so this up-style is sometimes called the “faux-hawk.” It calls for gathering the top section of your hair -- mostly your bangs -- twisting them towards the back of the head and securing with two crisscrossed bobby pins. If you have a few minutes to spare, you can also try back-combing or teasing along the hairline and smoothing out the outer edges with a brush to create a smooth bump up top.

Shiny Side Part and Braids
Brush out all tangles and create a clean part on your preferred side. You can do this neatly with a tail comb, which works even better on damp hair. Use the comb to push hair backward so you create a visible gap between wet wisps to part hair precisely. Next, rub a coin-sized amount of shine serum between palms and evenly distribute throughout locks. Finish the look by pinning hair to the side. If you’re not in a big rush, try braiding the front part to form a face-framing “hair band.”

Make Like the French
When all else fails, slip on a chic beret (military print is on-trend this season) or even a floppy hat. Whatever hat or cap you choose, just be sure it makes sense in relation to your surroundings. Bonnets in hot summer weather are unfashionable and impractical, and trucker caps are a no-no if you’re working in a corporate setting. You can also accessorize a less-than-stellar coif with a bright scarf with a sophisticated print worn as a headband.