You know that dusty, lint-like stuff you find in your hairbrush? It’s mostly dead skin cells shed when your scalp rejuvenates. Our bodies are constantly shedding dead skin cells — almost 500 million a day. While the shedding process is the same for our face and body, we tend not to see our bodies’ dead skin cells as they wash away in the shower. But for our scalps, it’s a little different. When we brush or comb our hair, the dead skin cells can peel off and get stuck in the hairbrush. So if you’re wondering “Are you supposed to wash hair brushes?” The answer is yes.

“Just like you clean your makeup brushes or skin-care tools, it’s necessary to clean hair tools—all of these items are breeding grounds for bacteria. Product, dead skin, dust, lint, and more can accumulate on your brush, and if you don’t clean it, you’re spreading all that back into your hair,” says celebrity hairstylist Kendall Dorsey. “Brushing also helps redistribute the oil from the scalp and keeps your hair shiny. If you don’t clean your brushes regularly or correctly, you may be redistributing old product or dead skin back onto the hair, making clean hair dirty again.”

Gross. Is it really all dead skin in there?

While the majority is a buildup of dead skin, the unsightly grub also consists of a mix of sebum, strands of hair, and styling products.

“Dander or dead skin cells appear in the hair and flake off in large numbers,” says Dominic Burg, PhD, chief scientist and hair biologist at Evolis Professional. “It’s quite normal to shed skin, as it’s constantly replenishing itself.”

Can the buildup affect the hair and scalp?

Yes, it can. The purpose of a hairbrush is to maintain your mane, so when the tool is dirty, it’s only doing your hair a disservice. A dirty brush can lead to more hair breakage, and the gunk can get attached to your clean locks, causing your scalp to feel itchier and be more dandruff-prone. And while it’s not great to use a dirty brush as it can assist with distributing sebum and bacteria, you shouldn’t be too concerned, says Beverly Hills hairstylist Jael. “It can impact us,” says Jael, adding that it’s nothing to stress out about.

Still, if you’re wondering: The average hairbrush is said to house around 3,400 bacteria colonies per square inch, according to a University of Arizona study. The scientists tested 30 hairbrushes owned by women between the ages of 16 to 24, all of whom regularly used various styling products. In comparison, the average bathroom sink had 2,733 sets, and pet food bowls had 2,110 bacteria colonies per square inch.

So do I get rid of the gunk?

Now that you know that this dust is not good for you, you’re probably wondering, “How do I clean my hairbrush?”First things first, you’ve got to remove all the loose gunk and hair.

“If you have a plastic brush, simply remove access hair from the brush with your fingers,” Dorsey says. “If you’re using a boar bristle brush, the natural bristles tend to be packed tightly together. Because of that, it’s easier to remove access hair with a comb or the pointed end of a comb.”

To remove hair from your hairbrush, you can use a rat tail comb or a specific hair brush cleaning tool.

LLTGMT, Rat Tail Comb for Hair Stylist — $4.00

Olivia Garden, Brush Cleaner — $17.00

Next comes the actual cleaning part, and there are tons of methods to try. Keep reading to learn how to clean plastic and boar-bristle brushes.

Does it matter what type of brush I have?

Yes. If you have a plastic-bristle brush, you can soak the brushes in the below solutions. If you have a boar-brustle brush, swirl the brush in the mixture instead of letting it soak. But beyond that, whether you’re using detangling brushes, brushes for fine hair, or brushes for curly hair, they all need to be washed.

What do you soak hair brushes in to clean them?

1. Soak it in baby shampoo and water

“Grab a bowl of water and add a few drops of baby shampoo,” says Dorsey. Place your plastic brush in to soak or swirl your boar-bristle brush. “Next, rinse the remaining soap and loosened debris out and use your comb again to make sure no dirt is left behind. Shake it out and place it face down on a towel to dry.”

Using baby shampoo ensures that it’s not silicone-based or creamy, notes celebrity hairstylist Philip B. On Mane Addicts, he explained that creamy shampoos “contain fats and lipids that prevent the breakdown of oils on the brush.” And wouldn’t that defeat the purpose of cleaning your brush in the first place?

Johnson's Baby, Tear Free Gentle Baby Shampoo — $6.00

2. Peel the dust away with Elmer’s Glue

A recent TikTok video by Maddie5pr revealed how Elmer’s Glue can remove the debris. Yes, the same glue you used in arts and crafts in school.

In the video, they poured the water-soluble glue all over the brush and left it to dry. Once set, it just peels right off, along with the hair and gunk. While many users were fascinated and impressed by the unique technique, others noted that the brush should be sanitized afterward to ensure full safety.

Elmer's, Washable No Run School Glue — $4.00

3. How to clean hair brushes with vinegar and baking soda

If you’d rather keep your glue for your next art project, your pantry has everything you need. Hair expert Jonathan Monroe revealed how mixing 1 Tbsp baking soda and 1 Tbsp apple cider vinegar in a bowl of warm water does the trick. After using a rat tail comb to remove the hair, he created the “stripping wash.” With the brush in the liquid mix, he used a toothbrush to scrub each column and row before leaving it on a clean towel to dry.

Arm & Hammer, Baking Soda — $12.00

Bragg, Organic Apple Cider Vinegar — $5.00

Mouthwatchers, Manual Toothbrushes — $18.00

4. Spray the brush with rubbing alcohol

If you don’t want to soak your boar-bristle brush, hairstylist Laura Frazier known as @hairzilla on TikTok, says you can clean it with rubbing alcohol. Once all that loose hair and gunk is removed as best as you can, spray it down with 99 percent rubbing alcohol until it’s saturated and then let it dry.

Alliance Chemical Store, Isopropyl Alcohol 99% — $27.00

Now that your brush is clean, learn how to brush your hair the right way, according to your texture.