Short men are in greater danger of losing their hair early, because both are in their genes.
Men who feel they have lost the genetic lottery by being short may be unhappy to hear the same genes could cause their hair to fall out.
But the testosterone which can cause boys to stop growing early, by closing the plates at the end of their bones during their teenage years, is also thought to cause baldness.
The largest genetic study of male pattern baldness has confirmed four locations in men’s genes which cause them to be both vertically and follically challenged.
Researchers at the University of Bonn analysed data from around 11,000 men with premature baldness and around 12,000 with no hair loss.
The findings highlight the importance of testosterone, which can trigger early puberty in boys and stop them growing.
The male sex hormone is also a key reason for baldness, being produced in the testes, then circulating in the blood and binding to a receptor in the hair follicles.
Lead author Dr Stefanie Heilmann-Heimbach said: ‘Genes that increase the risk for baldness can also lead to earlier puberty and shorter stature, likely because all these factors are all influenced by hormones.
‘The hormones may act very slowly, over years, so it only appears 20 years after puberty.
‘I would reassure men that being short does not definitely mean they will lose their hair. If you are short and all the men in your family still have their hair, it is probably unlikely, and tall men can go bald too. But there are biological pathways which contribute to both traits.’
Half of British men can expect to lose their hair by their 50th birthday, with famous sufferers include Elton John, footballer Wayne Rooney and actor James Nesbitt.
Male pattern baldness, the most common cause, was recently found by Edinburgh University to be linked to 287 genetic differences which could pave the way to a drug to stop it happening.
The only cure already identified is certainly too drastic for most men, as being castrated prevents hair loss completely.
The latest study goes some way to explaining why, highlighting that testosterone produced in the testes can cause ‘accelerated progression of puberty’.
The largest genetic study of male pattern baldness has confirmed four locations in men’s genes which cause them to be both vertically and follically challenged (file photo)
Men who go through puberty early also often undergo early closure of their epiphyses – the ends of the bone which are covered with cartilage for growth until they ossify to be replaced by bone.
When this happens, people stop growing, which can make them shorter as adults than their peers.
The research, published in the journal Nature Communications, states: ‘Associations with four loci were found for MPB (male pattern baldness) and lower body height, which may be driven by an accelerated progression of puberty and premature induction of epiphyseal closure.’
The international study, which took in the genes of more than 20,000 men across seven countries, also linked premature hair loss to an increased risk of prostate cancer.
The association with heart disease is much more complicated, with genes found which both cut and increase the risk.
Professor Markus Nöthen, director of the Institute of Human Genetics at the University of Bonn, said: ‘We have also found links to light skin colour and increased bone density.
‘These could indicate that men with hair loss are better able to use sunlight to synthesise vitamin D. They could also explain why white men in particular lose their hair prematurely.’
However, the molecular mechanisms which underlie the links between premature hair loss and other illnesses are only understood to a certain extent.
Previous studies have found as many as 500 genetic associations between baldness and height in men. In future scientists hope to determine exactly how much more likely short men are to lose their hair.
Source: Dailymail