Why do women suffer hair loss and thinning hair?

Male pattern hair loss, known as Androgenetic alopecia, is genetic and not limited to men, though rarer in women. It's more common post-menopause and said to be caused by a genetic sensitivity of hair follicles to male hormones (androgens). Rather than total hair loss in women, androgenetic alopecia tends to result in a more diffuse, all-over thinning, especially on the top and sides of the head. Unfortunately, there's no magic cure, though treatments can include using minoxidil lotion. Some people won't respond to it, but for those who do, it can slow hair loss. Proper regrowth is less common.

In younger women, contraceptive pills such as Yasmin and Dianette can have a positive effect on hair thinning as they have an anti-androgen action. Likewise HRT, designed to boost oestrogen levels as they fall during the menopause, often has a beneficial effect on hair, too. However some of the drugs used, such as tibolone, may contribute to hair loss, so you should discuss exactly what you are taking very carefully with your doctor.

Sudden hair loss in the form of one or more bald patches, known as Alopecia areata, is thought to be a disease of the auto-immune system, though there's also a genetic component. Hair follicles are attacked by the body's immune system, fast forwarding hair to its shedding phase. If you have eczema or asthma you may be more prone to alopecia. Treatment, which must be under medical supervision, can include corticosteroids - topical, oral or injections - and immune suppressive drugs. Some also claim results with Retin A gel (a vitamin A derivative used for acne and sun damage) rubbed into bald patches, either alone or with minoxidil. As hair follicles are still active, there is potential for hair growth, but it's hard to predict whether some or all of the hair will grow back.

Could you have an iron deficiency?

An often overlooked cause of hair loss, iron deficiency is very common, especially if you have heavy periods or avoid red meat, according to Dr Fenton. It's easy and cheap for your GP to do a blood test to check iron (haemoglobin) levels, plus ferritin levels. Ferritin is an iron storage protein. If it is low or even at the lower end of average, iron supplements may help, says trichologist Philip Kingsley, and could show results within months.

Is your diet as good as it could be?

A diet lacking in nutrients will show in the way your hair looks and behaves. Protein is vital for the formation of keratin - the main component of hair - so it makes sense to include good sources, such as meat, eggs, nuts and fish. B vitamins, found in brown rice, nuts, beans and wholemeal bread, also play a role in hair growth. A B-complex supplement can be useful for perking up hair and nails.

To help absorption of vitamin B and iron (see above), nutritionist Ian Marber, aka The Food Doctor, suggests taking a course of probiotic capsules (from health food stores), with 8 billion-plus live bacteria for one week a month. This kind of probiotic can, however, be expensive.

Have your thyroid levels checked

Under and over-active thyroid conditions can cause hair loss, says Dr Fenton. Over-exercise and regular dieting can affect thyroid function, too. Blood tests at the GP or under the supervision of a dermatologist will show thyroid status and thyroid hormones can be prescribed, if appropriate.

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