The average human head has 100,000 hairs. Hair is made in hair follicles (the root of the hair). Each hair grows for about three years before it drops out and a new one grows. We lose 40-120 hairs a day with out even noticing!

Hair loss is a problem when a noticeable amount of hair falls out. It is usually associated with old age but there are lots of other reasons why you can start to lose your hair.

What causes hair loss and who can get it?

Hair loss can actually happen at any time of life. Whenever it happens it often makes people less confident about themselves and worried about the way they look.

There are lots of different causes of hair loss that affect different people:

• Male-pattern and female-pattern baldness – This is hereditary hair loss and thinning that is passed down from your parents. It occurs when your hair follicles start to shrink. This makes the hair get thinner and weaker. This type of hair loss is most common in older men.
• Alopecia areata – Alopecia is linked to problems with the immune system, such as an immune disorder, but can happen randomly for no apparent reason at all. Hair follicles are not permanently damaged. It is usually seen in young people and in most cases the hair will grow back.
• Illness – Some conditions such as anaemia (disorder of the blood), can make you lose some of your hair. Drug treatment for cancer can also cause your hair to fall out.
• Trichotilomania- This is a psychological condition that gives you an overwhelming urge to pull out your own hair. It is a compulsive disorder and not just a bad habit. It is more common in young people.
• Infections - Fungal infections of your skin such as tricophyton tonsurans can affect your scalp, causing itchy flaky skin and patches or hairloss.

What are the signs and symptoms of hair loss?

• Male-pattern baldness  – It is called this because hair loss follows a set pattern. The first stage is a receding hairline. The hair then gradually thins and falls out until you are completely bald. This gradual hair loss can start to happen in men any time after their late twenties.
• Women's hair  – Women’s hair loss or female pattern baldness is slightly different to men’s. Women’s hair gradually thins with age but they only tend to lose hair from the top of the head.
• Alopecia areata  – This causes patches of baldness that are about the size of a large coin. They usually appear on the scalp. There are usually no other symptoms.
• Infection – Fungal infections can cause your skin to become inflamed, itchy, dry and flaky. When this happens on your scalp it can cause patches of hair loss as well.

How is it hair loss normally diagnosed and treated?

It is usually quite obvious if you are losing your hair. You or your doctor will be able to tell just by looking at your head.

If hair loss is caused by an infection or a condition such as anaemia, treating the infection or condition can stop you losing more hair.

Often with illness your hair will start to grow back naturally after treatment. For example, after chemotherapy for cancer.  Whilst you have no hair you can wear a wig or headscarves, if this makes you feel better.

If you have inherited the genes that causes male-pattern or female-pattern baldness there is not a lot you can do once you start to lose your hair.

There are some treatments for hair loss. These just slow down the process.

What’s going to help?

Even though you can’t stop hair loss you can try to look after your hair. Wash it regularly, get it cut every few weeks and avoid heavy styling that can damage your hair.

Also make sure you’re eating enough protein (fish, dairy products and meat) and enough iron (from red meat and green leafy vegetables) in your diet. A bad diet can cause hair loss.

Looking forward

Hair loss, due to illness, is often only temporary. Hair loss later in life is permanent but it is very common. It happens to a lot of people and, when the time comes, there is no need to be embarrassed or depressed about it.

For more help and information

If you would like to know more about hair loss, please ask your doctor.

The British Skin Foundation

Last reviewed by Great Ormond Street Hospital: 21 September 2007

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