Causal Factors of Female Baldness

A human hair grows for two to six years. At any one time, 90 per cent of our hair is growing, while the remainder is in a resting state (known as the telogen stage) for between two to six months, before it falls out.

The hair follicle itself then rests for three months before the whole process is repeated.

AUTUMN

Researchers found that women had the highest proportion of resting hairs in July — with the telogen state in most of them ending around 100 days later, from October onwards.

This pattern is thought to be evolutionary: the body holds on to hair to protect the scalp against the summer’s midday sun.

Autumn is not the only cause of unexpected hair loss.

Hair is an incredibly sensitive barometer. Hair cells are the second-fastest produced cells in the body (after bone marrow), so hair is often the first thing to suffer from any bodily upset. It can even forewarn you when there are no other symptoms of illness.

That’s because we don’t need our hair for survival, so if it’s a choice between your hair growing or keeping blood going to the vital organs, the former will suffer.

MEDICATION

A number of medications can trigger hair shedding. It is thought that drugs switch more hairs from the growing into the resting phase, and these hairs are then shed a few months later.

Certain prescriptions for acne are thought to cause unexpected hair loss in 16 per cent of people taking it.

Beta-blockers (for high blood pressure), anti-coagulant (blood-thinning) drugs, antidepressants and non-steroidal anti-inflammatory drugs have also been linked with hair loss, although why isn’t clear. However, for blood-thinning drugs, it is probably a question of balancing how bad the hair loss is against the reason they are on the drug in the first place. Usually the drug wins.

IRON DEFICIENCY

In premenopausal women, lack of iron is the most common cause of hair loss. Most of the iron stored in the body is bound to ferritin — a protein which helps in the production of hair cells and guards against hair shedding.

The three main causes of iron deficiency are a lack of iron in the diet, heavy periods and childbirth (because of blood loss).

Shedding between 40 and 120 hairs a day is normal; if you’re shedding more than usual, ask your GP for an iron test as well as a ferritin test. The normal range for iron is between 2 and 150 nanograms per millilitre, but we need a level of at least 70 to get good, healthy hair growth.

So you may show up as fine on a test, yet there isn’t a sufficient store for hair growth. It’s worth having both ferritin and iron levels checked for anaemia, as this is a specific marker for female hair loss.

Iron deficiency can also be triggered by coeliac disease — an intolerance to gluten (a protein found in wheat, barley and rye). This affects the gut’s ability to absorb food properly, so the body lacks nutrients including iron.

The good news is that hair growth resumes once the coeliac disease has been diagnosed and treated.

Good food sources of iron are red meat, egg yolks and green, leafy vegetables. Vitamin C helps with the absorption of iron, so have a glass of orange juice when eating.

However, the tannins in tea can stop iron being absorbed properly, so don’t drink tea with meals or at the same time as taking iron supplements.