I Should Know This

Why Is My Hair So Dry And Brittle?

Two hairstylists and a trichologist tell all.

Written by Jill Di Donato

As a single mom of a preschooler, I don’t know what I was thinking when I dyed my hair platinum. Nothing is as high-maintenance as platinum, and when you skimp on hair care, it shows. My texture suffered: Dry, brittle hair? Check. But what can I say? I love blonde. It’s my one indulgence in an otherwise low-key beauty routine. But because damaged hair can mire your look, and because hair care is the new self-care, I tapped a trichologist and two celebrity hairstylists to explain the causes of dry, brittle hair. They share tips on everything from the correct way to use heated styling tools to things you can do while you sleep for shinier hair. The key, notes celebrity hairstylist Andrew Fitzsimons, is to “follow a step-by-step process to ensure your hair stays healthy.”

Ahead, find common causes of dry, brittle hair and tips on how to maintain healthy tresses.

1. Excessive use of heat

It’s tempting to reach for the straightener to smooth out a frizzy mane. But approach with caution: One of the most common causes of dry, brittle hair is styling with tools that require heat. Good news, though — you don’t have to quit your hair iron cold turkey. The pros advise selective use of heated tools, rather than giving them up completely because, let’s be real, they’re a necessity.

“For people using styling tools on their hair, I would recommend only using them three to four times a week,” says Linh Phan, celebrity hairstylist and founder of PhanHaus. “And keep the temperature below 400 degrees Fahrenheit.”

Dominic Burg, Ph.D., trichologist and chief scientist at Evolis Professional, also notes that you should never use heat directly on damp hair. “Always make sure your hair is dry before using styling tools,” he says. “If your hair is still damp, you run the risk of flash boiling the residual water inside your hair shaft, which can cause extensive damage to the hair structure, leading to brittleness.” And this isn’t just for hair tools — this includes being more mindful of your blow-drying technique. “Blow-dry on a cool setting to remove excess moisture first,” he says. “Don’t use too high a heat, and use a good quality heat protectant before you style.”

A heat protectant preps your hair, so that the cuticle doesn’t get completely fried as you blow-dry. Drybar’s Prep Rally Prime & Prep Detangler and Bumble and Bumble’s Invisible Hair Dresser’s Invisible Oil Heat & UV Protectant Primer are both good options that work across all hair types and won’t weigh your hair down in the process.

Another tip is to alternate heatless styling with heated styling to give your hair time to recover. “Opt for a heatless curl style that can be worn for a few days and only use the hot tool to refresh your style,” says Fitzsimons.

Perfect Silk Beauty Set For Hair from LilySilk contains a curling band, scrunchies, pillowcase, and sleeping cap for you to achieve a heatless curl, while protecting your hair with silk while you sleep. If you already have a naturally curly or coily hair type, a protective style like cornrows or bantu knots will keep your hair healthy by limiting its exposure to heat and the elements.

2. Over-bleaching your hair

Over-bleaching your hair causes major damage (obviously). To mitigate, Burg suggests jumping on the scalp care bandwagon, a buzzy hair care ritual that can help reverse the damage of over bleached hair. “You need to start with a strong foundation,” he says. “If your hair grows optimally, it will withstand repeated coloring. Invest in a good scalp and follicle care routine to make sure you are growing the best hair you can so you can approach color and treatments with less fear of brittleness and dryness.” Briogeo Scalp Revival contains charcoal and coconut oil to ease dry scalp for healthier hair; Act + Acre Scalp Detox breaks down sebum and removes build-up on the scalp.

Of course giving the bleach a rest for a little while can’t hurt, either. “If your hair is already dry and brittle, perhaps you should think about backing off from the color and giving your hair a break,” Burg suggests. But if you simply cannot get off the bleach train, he recommends using a deep-conditioning treatment mask overnight. “Apply liberally and let it deeply nourish your hair while you sleep,” Burg says. “Some, like the Evolis masks, form a protective shell that won’t get onto your pillows overnight. Others will need to be wrapped in a towel or turban while you sleep.”

3. Washing your hair too much

Over-washing your hair could be damaging your tresses. Every time you wash your hair, you damage it,” Burg explains. “Shampoos strip out the natural oils and damage the protective wax layer of the hair, opening the cuticles and allowing in the penetration of water.” You might think that water adds hydration, but for your hair, it actually has the opposite effect. “When water enters the hair fiber, it weakens the internal structure, leading to brittleness and allowing dryness over time,” he says.

4. Using the wrong products for your texture

Different hair textures require different types of products. According to Phan, using the wrong products for your hair texture can actually cause damage. Fitzsimons agrees, explaining that “curly or coily hair tends to be on the dry side, and therefore more prone to breakage. Due to its tight curl pattern, the natural oils can’t easily make their way down the hair shaft.”

Naturally Drenched Rebalance is a pH-balancing hair treatment for textured hair with coils and curls. Other editor faves for textured curls and coils include Imbue Curl Inspiring Conditioning Crème Gel and Bread Beauty Supply Hair Cream.

Phan goes on to say that if your hair appears to be drier than usual, you can restore moisture by deep conditioning weekly. For blonds, Phan recommends Schwarzkopf Blondme Detox Mask or K18 Molecular Repair Mask.

“Consider using a silk pillowcase or bonnet before you go to bed to protect your hair,” he says. “You won’t be able to restore your dry hair overnight, but with time and patience, your hair will soften.” Slip Silk Pillowcase and Good Side Silk Pillowcases are cloud-soft and instantly make your bed feel like a luxury experience.

5. Overdoing it with sulfates

Dryness might result from using a hair care product that contains synthetic ingredients like sulfates, which Burg says “can over-strip hair’s natural oils.”

According to Fitzsimons, products with sulfates “can irritate your scalp and cause dryness. Switching to sulfate-free and products with more naturally-derived ingredients as an alternative can help you obtain healthier hair and scalp.”

Actsyl’s Growth Stimulating Shampoo is a sulfate-free formula that uses tea tee oil to gently clarify and sodium hyaluronate and biotin to strengthen the hair. Or, try Pantene’s Sulfate Free Castor Oil Shampoo for Damage Repair, which uses a coconut-derived ingredient to gently cleanse the hair without over-stripping.

6. Letting your hair air dry

Did you know hair is most fragile when wet? “The longer hair stays wet, the more damage occurs to the internal structure,” Burg says. “Drying hair with a blow-dryer on a cool setting is an important way to minimize any damage.”

Aquis makes the Rapid Dry Lisse Hair Towel, a microfiber towel that gently dries wet hair in its most fragile state without causing friction or frizz.

7. Not getting your hair trimmed

Fact: Going to the hair salon to get a haircut can be a time-suck. Also a fact: Making the time to get a trim on a regular basis can really improve your hair texture. “Trimming your hair at least once every eight weeks keeps it healthy and free of split ends,” Fitzsimons explains. “When you have split ends, the split cuticle can travel up the hair shaft.”

While at the salon, consider a professional treatment that can really accelerate results. If your hair is straight and wavy, Phan recommends a Brazilian Blowout or keratin treatment to smooth cuticles and lock in moisture. If your hair is coily or kinky, consider a salon gloss or in-salon conditioning treatment, like Olaplex 4-in-1 Moisture Mask.

I Should Know This is a back-to-basics series where we ask top experts for the answers to all your burning beauty questions, judgment-free.