Male pattern baldness explained


You might be surprised to learn that we all lose between 50 and 100 hairs a day. However, most of us don't experience this as hair loss because new hair grows in its place.

By the time they reach 50, half of all men will experience some form of male pattern baldness (MPB). This is where hair in certain areas of the scalp is not renewed properly, causing the hair to thin and, over time, to fall out entirely. By the age of 60, most men will have some level of hair loss.

There are treatments that can help, but they're not effective for everyone. Hair loss is a very normal part of growing older, and many men accept it and don't attempt to treat or reverse it.

What is male pattern baldness?

MPB (medically known as androgenic alopecia) usually starts becoming noticeable in men who are in their late 20s or early 30s. However, it can begin affecting males at any time after the onset of puberty.

Pattern baldness progresses at different rates in different men. Early onset MPB tends to progress more quickly than in men who begin losing their hair later in life.

The most common pattern of hair loss is a receding hairline. This is followed by thinning of the hair on the crown and the temples.

This hair loss continues to progress, until all that's left is a horseshoe-shaped area of hair covering the back and sides of the head. Occasionally, MPB can leave the head completely bald.

Pattern baldness can also affect women, although this is far less common. Women usually experience hair loss as a general thinning of hair on top of the head.

What causes male pattern baldness?

MPB runs in families, and can be inherited from one or both parents. The changes to hair are caused by male hormones. In MPB, hair follicles become more sensitive to dihydrotestosterone, which is made from the main male hormone testosterone. This sensitivity causes them to shrink. Over time, hair produced by follicles affected by these hormones becomes increasingly finer, shorter and lighter, until no more hair is visible.

The causes of female pattern hair loss are less understood.

What can I do about male pattern baldness?

Some men find losing their hair distressing, and choose to try to treat their hair loss. There are products available that are designed to slow the rate of hair loss. Such products are based on two medicines  minoxidil and finasteride.


Minoxidil was discovered during trials for a high blood-pressure treatment, during which it showed signs of being able to regrow hair.

Minoxidil-based products are applied as a liquid or foam to the scalp. They are designed to work by increasing blood flow to the hair follicles, which can stimulate hair growth.

Minoxidil can be taken by both men and women.

Minoxidil does not work for everybody, and even in those it does help, it's effective only for as long as it's being applied. Once you stop the treatment, regrown hair is likely to disappear within three to four months and your hair loss will continue at the same rate as before.

The medication contains either 5 percent or 2 percent minoxidil. Evidence about which is more effective is inconclusive.

Side effects are also more likely to occur with the higher-strength products. Side effects can include scalp dryness and itchiness, changes to the texture of your hair and heart palpitations.


Finasteride is a prescription only medicine for men aged 18 and over, available as a generic or as the brand Propecia. It works by lowering androgen levels in the bloodstream, allowing hair follicles to regain their normal size. You need to take finasteride for between three to six months before seeing any benefits. Once you stop taking the tablets, hair loss will generally revert to pre-treatment levels within nine to 12 months.

Side effects can include a loss of sex drive (libido), as well as the inability to get or maintain an erection (erectile dysfunction). Finasteride should not be taken by women.

When should I see my Doctor?

Although MPB will not cause you any medical problems, for many of us, hair is an important part of our identity. Going bald can therefore be upsetting, particularly for young men. Some men are so distressed by hair loss that they'll consider paying for expensive cosmetic procedures, which can be painful and are not always effective.

Such procedures may include:

  • Scalp reduction. Sections of hairless scalp are replaced with hair-bearing scalp, which are stretched and stitched together
  • Hair transplant. Hair cells are moved to thinning areas
  • Artificial hair transplant. Artificial hairs are surgically inserted into the scalp
  • Tattooing. The scalp is tattooed to resemble hair stubble

If your hair loss is causing you distress, speak to your Doctor straightaway. They may be able to refer you for counselling, or to a support group.

If you're experiencing sudden hair loss, or you're losing it in clumps, visit your Doctor. You might have an underlying (and treatable) condition that needs addressing.

Next steps

  • Going gradually bald is a normal part of the ageing process for men. It won't cause you any medical problems
  • If you are distressed by your hair loss, speak to your Doctor. They may refer you to a counsellor or support group
  • Speak to your pharmacist about the different hair loss treatment options available to you