Every day, you lose about 50 to 100 hairs. You've seen them. They swirl down the drain in the tub or get stuck on the back of your sweater. Or, worst of all, one might get in your mouth. Gross.

Normally, when hair falls out, new hairs start forming in the same place as the old ones. But when someone has hair loss, the hairs may not grow back. Or they do grow, but there aren't enough of them to take the place of what's already fallen out. This often happens to men, who might start to go bald as they get older.

But anyone can have hair loss, even kids. The medical name for hair loss is alopecia (say: al-uh-pee-shuh).

The Hair-y Story

The hair on your head is made of keratin (say: kair-uh-tin), the same protein that makes up your nails. Hairs grow from follicles (say: fahl-ih-kulz), which are very tiny holes deep in your skin. Each follicle contains a hair root, the part of the hair that is alive and growing. The part of the hair you can see, the part above the skin, is dead. (That's why it doesn't hurt to get a haircut!)

This part is called the hair shaft and it's the part of your hair that can get long. Most kids' hair grows about half an inch (2 centimeters) a month. About 85 out of 100 hairs on your head are growing (the anagen phase) at any time. When a hair is done growing it goes into its resting (telogen) phase and eventually falls out. Usually, 15 out of 100 hairs on your head are in the resting phase.

What Causes Hair Loss?

Men, especially older men, are the ones who are most likely to lose their hair. This kind of hair loss is called androgenetic (say: an-dro-jeh-neh-tik) alopecia, also known as male-pattern baldness. It's the most common type of hair loss and it doesn't affect kids. This type of baldness runs in families and happens when people get older.

So why do some kids lose their hair? A kid's hair may fall out if he or she uses harsh chemicals to dye, bleach, straighten, or perm the hair. Even drying hair with very high heat can hurt it and cause it to fall out. Too-tight braids, ponytails, and barrettes also can make hair hit the road. And hair can be lost if a person combs or brushes the hair too hard, especially when it's wet.

Here are some other causes of hair loss:

• Telogen effluvium (say: teh-luh-jen eh-flu-vee-um). This means that more hairs than usual are in the resting phase and fall out more easily. As a result, you lose more hair than usual. You might notice more hair on your brush or a big clump of hair in the drain after you shower. A fever, stress, or surgery can cause this change in your hair. The good news is that you're not going bald and your hair will be back to normal within 6 months.
• Ringworm. Kids who have a fungus called ringworm on their scalp might lose their hair. This infection causes the hairs to break close to the scalp.
• Alopecia areata (say: ar-ee-at-uh). In this condition, round patches of hair completely fall out. No one knows exactly what causes alopecia areata, but it looks like the body's own immune system attacks the hair follicles. It also runs in some families. In 95 out of 100 cases of alopecia areata, the hair grows back completely.
• Trichotillomania (say: trik-oh-till-oh-may-nee-ah). This is the fancy name for the habit of pulling and twisting your own hair. Some kids may pull their hair because they're stressed out or anxious about something. Hair will grow back when it's not being pulled, but some kids find it hard to stop. For these kids, the doctor can recommend treatment.
• Hormone problems. If your thyroid gland isn't working right, it can also cause hair loss. (The thyroid gland sits in the front of the lower neck and makes important hormones that keep the body healthy.) Severe problems with nutrition also can result in unhealthy hair that falls out or breaks easily.
• Cancer treatment. Most people think about cancer when they see a kid who is bald. Cancer does not cause hair to fall out, but the powerful drugs and treatments used to kill cancer cells (chemotherapy and radiation) kill the cells that make hair grow, too. A kid getting chemotherapy may lose a lot of hair quickly, but the hair will grow back when the treatment is stopped.

What Will the Doctor Do?

If you think you're having some hair loss, talk with your doctor. Your doctor might look at a few strands of your hair under a microscope. This will give the doctor a better look at what's going on to help decide what to do next.

For a fungal infection (ringworm), the doctor will probably prescribe some medicine to treat it. Or if you are taking a medication that can cause hair loss, the doctor might stop it or prescribe something different. If the doctor thinks that an illness is causing the hair loss, you might need more tests.

Coping With Hair Loss

In some cases, it can take a while for hair to grow back on its own — especially if a kid has alopecia areata or is getting chemotherapy. Being bald can be upsetting and scary. Some kids wear wigs or hair extensions while they wait for their own hair to return. Others feel more comfortable just wearing a baseball cap, bandanna, or scarf.

It's always tough to be different, especially in a way that's easy for people to notice. Friends and classmates can make all the difference to someone who's dealing with hair loss. They can tease the person and make him or her feel even worse. Or they can support the kid, be kind, and remember that a person is more than just his or her hair.

Some kids have really gone the extra mile for a friend who had hair loss due to cancer treatment. How? They decided to shave their heads, too, so their friend wouldn't be the only one. What a bald and beautiful thing to do!

Reviewed by: Patrice Hyde, MD
Date reviewed: October 2011