The Top Haircare Mistakes That Cause Dry, Brittle Hair

Like your skin, the cause of dryness in your hair can be due to a wide range of reasons. But when you think about it, it’s understandable that your hair goes through a lot. Overprocessing your hair, frequently using hot tools, or spending too much time in the sun are all ways that can weaken the hair, warns trichologist and hairstylist Penny James. She refers to this type of brittle hair as “acquired brittle hair” because it’s not caused by natural factors. In short, when it’s not caused by a medical condition or poor nutrition, brittle and dry hair happens when we do things to suck all the moisture out of it.

Meet the Experts

Not to be confused with thinning hair, if your hair shows signs of brittleness, it appears lackluster in color, rough in texture, susceptible to frizz, and shows signs of damage like split ends. When you pull or stretch a strand of brittle hair, it’s likely to break off, explains celebrity hairstylist and licensed cosmetologist Tenisha Sweet. “The hair follicle is made up of three layers — the cuticle (outer layer), the cortex (middle layer), and the medulla (inner layer) — and when it becomes brittle, it means that the elasticity (and sometimes the porosity) of the hair has changed, therefore causing the hair to break easily,” she says. “A healthy elasticity and porosity is very important and is necessary to lock in moisture.”

The best game plan to improve the appearance of brittle hair is to avoid the culprits in the first place. Here, hair pros share the most common mistakes that cause brittle hair and what to do instead.

Not consuming a healthy diet rich in nutrients

You know a nutritious diet is important for your overall health but may underestimate its vital role in the health of your hair. Eating a poor diet is one of the simplest ways to score dry, brittle strands. “Poor nutrition, particularly revolving around low iron, low vitamin D3, low B7, and B12 can create brittle hair because the building blocks of the hair shaft need to be created within the hair follicle utilizing energy from these vitamins and minerals,” explains William Gaunitz, F.W.T.S., certified trichologist and founder of Advanced Trichology. “When these nutrient levels are low, the little construction crew inside the hair follicle cannot form the amino acids of the hair properly, creating weak and brittle hair.” Fortunately, this is a quick solution: Improve the total volume of vitamins and minerals in your diet by increasing your consumption of iron-rich foods such as red meat and dark leafy greens.

Shampooing too often

Often, Sweet hears from her clients that they’re shampooing every day to rid their hair of excess oil. Unfortunately, their attempts are accomplishing the polar opposite, as over-washing, the hair can strip the scalp of its natural oils and nutrients, she explains. “When we overwash, our sebaceous glands (oil glands) respond with over-producing oil to make up for the oil that was stripped,” she says. Her advice is to transition to shampooing every other day gradually, then three times a week, and then twice a week. “Twice a week is safe, but don’t forget to condition and put the moisture back in — without moisture, your hair will become brittle,” she says. For curlier textures, she recommends shampooing once a week at the most. “It’s easier for curly hair to remain or become brittle because of the bend in the hair that creates the curl, so it is already naturally weaker,” she adds.

Over-processing your hair

According to Sweet, chemical processing without proper maintenance is an easy way to get brittle hair. “Anytime you are chemically processing your hair, you are not only stripping the cuticle of the hair itself but also the entire strand,” she says. “Chemicals break down the natural protein structure — leading to a change in texture, elasticity, and porosity, which, in turn, weakens the hair and causes breakage.” Her best advice is to stretch out the time between color and chemical treatments as much as you can — ideally three months or so — to rest your hair and take proper care of your hair in-between salon visits.

Using hot tools too frequently

Your blow dryer, straightener, and curling wand might be your go-to styling tools, but be careful about how often you’re using them. “The use of hot tools (or heat), over time, whether a blow dryer or a curling iron, can cause the hair to lose its strength,” says Sweet. “The keratin that we naturally have in our hair starts to go away, leading to a loss of elasticity, a change of the hair’s natural shape, and excess breakage.” She recommends air drying whenever possible — at least the majority of days during the week — and saving your hot tools for special occasions.

Not applying a heat protectant

On those occasions when you use hot tools (or spend a lot of time in the sun), one of the biggest mistakes you can make to cost you brittle hair is not applying a heat protectant. “Heat damage can drastically harm hair and cause it to become dry and brittle,” warns Annagjid “Kee” Taylor, celebrity hairstylist. “A heat protectant can shield from the excessive heat we may put on our hair daily through styling tools, or even a spray-on SPF to help protect from sun damage.” She recommends applying a hair protectant like Pureology Style + Protect Instant Levitation Mist or Moroccanoil Perfect Defense Heat Protectant over your hair just before you take a hot tool to your hair to prevent breakage and brittleness.

Combing your hair too vigorously

When combing hair, it’s important to be gentle and slow with your motions, taking small sections, starting at the ends first, and working your way up the hair shaft, explains James. “Start at the nape of the head, take small sections, work up to the crown, then start over the ears and work up to the center of the head,” she says. This helps prevent breakage and keeps your hair soft and supple.

Not using a deep conditioner

One of the best things you can do for your hair is to ensure it’s hydrated. The best way to do this if you have brittle hair is to use a deep conditioning mask at least once a week, according to Sweet. “After shampooing, grab your favorite deep conditioner, apply it and throw on a shower cap,” she says. One of her favorite deep-conditioning masks is Kérastase Discipline Maskeratine, which she says works on all hair types and does the job in 15 minutes.

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