Patterned hair loss

Patterned baldness is the most common cause of hair loss in both men and women, and is the result of genetic and hormonal factors. Hereditary baldness is so common that it is considered a normal part of the ageing process, and all men and women will be affected by it to some degree at some stage in life.

The pattern is different in men and women. Men develop recession at the temples, thinning and eventually a bald spot on the top of the head (the vertex scalp), and ultimately baldness over the whole crown. Hair above the ears and at the back of the head is relatively spared.

In contrast, women develop diffuse thinning over the entire scalp that is most pronounced over the crown. Complete baldness is seen in only a minority of women (less than five per cent).

Most men have developed some recession at the temples by their mid-20s and noticeable balding by their mid-50s. For most women, hair loss is mild and only appears later in life. When hair loss is premature or severe, however, it can cause distress, and a range of treatments is available to slow or reduce hair loss and stimulate partial regrowth.

How hair grows#

The human body is covered with hair follicles, except on the palms of the hands, the soles of the feet and the lips. Most follicles are tiny, and many of the hairs they produce never grow long enough to emerge from the pore. Hair is made from a protein called keratin.

The only living part of the hair is the root (sometimes called the bulb), which is attached to the base of the follicle. The follicle supplies oxygen and nutrients to the root and lubricates the hair shaft with an oily substance called sebum. Hair is in a constant cycle of growth, rest and renewal.

On the scalp there are approximately 100,000 hair follicles. Over about three years, each follicle produces a hair that grows, rests, falls out and then regrows. This means that, on average, around 100 hairs are shed each day. As long as the new hair that grows from a follicle is the same as the one it replaces, hair density stays constant.

Causes of hair loss#

In patterned hair loss, hormones affect the follicle, making it smaller, so the new hair becomes shorter and finer than the one it replaces. Eventually the new hairs are so short and fine they become invisible and the scalp appears bald.

It is likely that several genes determine susceptibility to baldness, some inherited from the mother’s side of the family and some from the father’s side. Identical twins tend to lose hair at the same age, at the same rate and in the same pattern, which indicates that genetic factors are more important than environmental ones in causing hair loss.

Androgenetic hair loss is caused by androgen hormones (produced in differing amounts by both men and women) acting on the hair follicles of people with a genetic susceptibility. Some people think that stress, diet, wearing hats, frequent washing, drinking alcohol or smoking cigarettes cause hair loss, but researchers have found no strong link between any of these activities and patterned hair loss.

Male pattern baldness (androgenetic alopecia)#

While there are a number of treatments for male pattern baldness, there is no cure. Treatments include:

• minoxidil lotion, available over the counter from pharmacies
• finasteride tablets, available only on prescription from your doctor

Cosmetic options include camouflage sprays, wigs and hair transplant surgery.

Hair loss in women (androgenetic alopecia)#

Hair loss in women produces scattered thinning over the top of the scalp rather than a bald spot. Patterned hair loss occurs in over half of women as they age. For most, the hair loss is subtle, but about 20 per cent of women develop moderate or severe hair loss.

A number of treatments are available for female pattern hair loss, including:

• topical minoxidil lotion (not recommended for pregnant or breastfeeding women)
• tablets such as spironolactone, which have antiandrogen properties (they lower the levels of male hormones)

These are available on prescription and require a doctor’s supervision.

Treatment for hair loss#

Although there is no cure for hair loss, a number of treatments can slow or reduce it, stimulate partial regrowth or replace damaged hair. Surgical hair transplantation can help some men with advanced balding.

Despite advances in understanding, there are limits to current treatment. In particular, age-related and inherited forms of hair loss are difficult to reverse, although treatment may prevent further loss and produce partial regrowth. Non-surgical treatments (lotions and tablets) generally need to be used continuously for the benefits to be maintained; if you stop, regrowth ceases and hair loss resumes. Cosmetic options include wigs and hairpieces.

A number of other treatments have been suggested for hair loss, including massage, vitamin supplements, herbal remedies (such as saw palmetto), zinc, amino acids, and hair lotions and tonics. None of these have been shown to promote hair growth or prevent hair loss, and there is no scientific evidence that lasers are effective. If you are unsure, talk to your doctor before starting any treatment.

Minoxidil#

Minoxidil lotion has been used for hair loss for several decades, and a number of brands are available from pharmacies without a prescription. Drops are applied to the scalp morning and night and rubbed in; a foam preparation is also available. Hair regrowth generally takes about six months to become apparent.

Finasteride#

Finasteride is the active ingredient in a men’s hair-loss treatment that has been available for several decades. One tablet a day will halt further hair loss in over 95 per cent of men and stimulate partial regrowth in about two-thirds of men. Regrowth may be apparent at six months but can take up to two years to be visible. Side effects are uncommon but include reduced libido and sexual dysfunction, occurring in around one per cent of men taking it. Finasteride requires a prescription from your doctor.

Spironolactone#

Spironolactone has been used for several decades to treat high blood pressure and fluid retention. It blocks the effect of androgen hormones. In women, androgens can cause oily skin, acne, unwanted facial and body hair, and hair loss on the scalp, and spironolactone can be used to treat all of these. It requires a prescription, and pregnant or breastfeeding women should not use it.

Cyproterone acetate#

Cyproterone acetate also blocks the effect of androgen hormones and is an alternative to spironolactone for women with patterned hair loss. It is a weak progestogen and is found in some oral contraceptives. It can also be used to treat acne, unwanted facial and body hair, and hereditary hair loss in women, and it requires a prescription from your doctor. It is not recommended as a treatment for hair loss in men.

Hair transplantation surgery#

Hair transplantation is a surgical treatment for hair loss. In early techniques, large plugs of hair were used, which sometimes gave unsatisfactory and unnatural-looking results. Today, small mini- and micro-plugs of skin, each containing between one and five hairs, are used. This modern technique does not produce very thick or dense growth, but it looks more natural and in many cases is undetectable as a transplant.

Types of hair loss that respond best to transplantation include androgenetic hair loss in men (the most common type that can be helped) and hair loss due to accidents or operations. The surgeon removes hair follicles from the back or sides of the scalp, where hair is less likely to fall out, and transfers them to the bald areas, placing them so they receive adequate blood flow during healing. A session may take several hours, and a person may need several sessions to get satisfactory coverage. Hair then grows from the transplanted follicles.

A sedative is usually given before the procedure, and local anaesthetic is used at the donor and recipient sites. As the anaesthetic wears off, you may notice some discomfort, which can be eased with simple pain-relieving medication.

Complications of hair transplantation surgery#

Complications can include:

• infection, because the skin is broken to perform the procedure; this can be treated with antibiotics
• bleeding, usually controlled through careful post-operative care
• scarring, which may occur where the donor follicles are removed
• temporary, operation-induced hair loss (telogen effluvium), which can occur after a transplant and some other operations, affecting roughly five per cent of people
• unacceptable cosmetic results, which are more common when transplants are carried out by inexperienced practitioners

Many clinics offer hair transplantation, but specialist dermatologists are best qualified to advise about this surgery and have the most knowledge about hair in health and disease.

Key points#

• Hereditary baldness is so common that it is considered a normal part of the ageing process.
• When hair loss is premature or severe, it can cause distress.
• Genetic factors are more important than environmental factors in causing hair loss.
• Stress, diet, hats, frequent washing, alcohol and smoking have not been shown to cause patterned hair loss.
• There are a number of treatments for male pattern baldness, but there is no cure.

Where to get help#