Hair grows everywhere on the human skin except on the palms of our hands and the soles of our feet, but many hairs are so fine they're virtually invisible.

Hair is made up of a protein called keratin that is produced in hair follicles in the outer layer of skin. As follicles produce new hair cells, old cells are being pushed out through the surface of the skin at the rate of about six inches a year. The hair you can see is actually a string of dead keratin cells. 

The average adult head has about 100,000 to 150,000 hairs and loses up to 100 of them a day; finding a few stray hairs on your hairbrush is not necessarily cause for alarm.

At any one time, about 90% of the hair on a person's scalp is growing. Each follicle has its own life cycle that can be influenced by age, disease, and a wide variety of other factors. This life cycle is divided into three phases:

As people age, their rate of hair growth slows.

There are many types of hair loss, also called alopecia:

Doctors don't know why certain hair follicles are programmed to have a shorter growth period than others. However, several factors may influence hair loss:

Some people notice hair loss when they lose more than 15 pounds. The hair loss usually starts about 3 to 6 months later, but the hair will grow back on its own.

Not only can they give you a headache, but tight hair styles like cornrows, ponytails, and pigtails can tug on hair and cause it to break -- sometimes for good.

Washing every day is OK. Just gently massage in the shampoo and don't rub too hard with a towel when you dry. It's a good idea to wear a loose-fitting hat outside to protect hair from the sun's UV rays.

Hormone changes during menopause can speed up hair loss, but it can happen at any age. 

Many women lose hair about 3 months after they've had a baby because of big hormone changes.

Some medicines, infections, diseases, and stress after surgery can also cause you to lose hair.

Because hair loss can be a sign of other problems, tell your doctor so you can get to the root of the issue.


Hair Loss Overview

Hair loss, or alopecia, is a concern for men, women, and children. Treatments for hair loss include medications such as Propecia and Rogaine, hair replacements, and hair restoration

It's OK to put down that hairbrush! 
Brushing that much can cause split ends and breakage. 

Also, use a wide-toothed comb. It keeps you from tugging at tangles and will do less damage.

Your best bet is to use conditioner first. 
Comb curly hair while it's damp and let straight hair dry a little first.