Most men, some women, and even children have to endure thinning hair or baldness, and sometimes a loss of confidence or embarrassment. Friends may joke but for some it can be an emotional crisis. Skin specialists say scalp hair loss can provoke more distress than many severe skin conditions but often is not taken seriously enough.

The scalp has around 100,000 hairs, growing about 1cm a month. Most people lose around 100 hairs a day without even noticing, as new hairs replace them. But renewal slows down as we age. Hair loss or baldness, known as alopecia, is usually gradual. It may be patchy or all over. It is not usually due to disease or excessive hair loss but rather the hair follicles get tired and fail to grow new hairs quickly, thickly and long enough to replace lost ones.

Male-pattern baldness (androgenic alopecia) – characterised by a receding hairline and thinning crown – is the most common type and is hereditary and normal. It can begin before a man reaches 20. One in four men are balding by 30 and about two-thirds are bald or balding by 60.

Gradual hair loss in men and women is usually due to a rebalanced metabolism of androgen hormones – testosterone is one.

For women, hair normally thins after the age of 50. Considerable hair loss before that is quite rare unless there is a health reason, such as an ovarian cyst, pregnancy or childbirth, even the pill can affect some women.

For 12 weeks after childbirth, hair shedding may speed up as the mother's hormones rebalance, but after six months it should be back to normal. For these women, the hair usually thins across the entire scalp, is temporary and generally leaves the front hairline intact.

You can do nothing about your age and genes but you can change your diet, make lifestyle choices, review medicines, hair care products and styling. Sudden loss of hair or hair coming out in clumps can be due to burns, infection, thyroid disease, chemotherapy, crash diets, medicines, excess vitamin A, severe stress or illness or surgery. It should be checked out by your GP.

Remedies depend on the type of hair loss. Some products available online should not be used by women or children and can have effects for some men.

Child hair loss is usually from scalp ringworm, easily treated with antifungal medicines. Hair loss in adolescence may be due to poor diet such as lack of protein or depression or stress.

Rosie, now 28, was 19 when she lost her hair. “I was very confident, loved my job, had plenty of friends but my long hair began falling out for no reason. My GP said these things happen. My confidence was shattered. After sharing my story online I realised I was one of thousands whose stories were the same. Good counselling identified my underlying stress and, yes, the hair grew back. I keep all my wigs to remind me that it is not so much about losing your hair but more about losing an important part of who you are.”

(Published in the Sunday News, 21 February 2010)

More everybody MYHEALTH columns from Barbara Docherty

Barbara Docherty is a registered nurse and clinical lecturer at the University of Auckland School of Nursing, and writer for the everybody.co.nz website. The opinions contained herein are those of the author and not necessarily those of the publisher or sponsor. Copyright UBM Medica (NZ) Ltd.