Early baldness and lower risk of prostate cancer link 'not conclusive'
Men who start losing their hair at an early age may be less likely to develop prostate cancer in the future, new research suggests.
But Cancer Research UK said that the results contradict those of previous studies and that further research is needed to provide more reliable evidence.
Male pattern baldness is a common condition that affects between 25 and 30 per cent of men by the age of 30, rising to nearly 80 per cent at age 70.
Writing in the journal Cancer Epidemiology, scientists at the University of Washington School of Medicine and the Fred Hutchinson Cancer Research Centre pointed out that male pattern baldness shares a number of characteristics with prostate cancer, in that both can run in families and are more likely as a person ages.
Furthermore, both male pattern baldness and prostate cancer are affected by levels of the male hormone testosterone.
The researchers studied a group of 999 men, aged 35 to 74, all of whom had been diagnosed with prostate cancer between 2002 and 2005, as well as 942 healthy volunteers.
They found that 25.2 per cent of cancer-free men had experienced hair loss at 30 years of age, compared with just 19.8 per cent of prostate cancer patients.
Overall, men with hair loss at 30 years of age were 29 per cent less likely to develop prostate cancer than those who did not experience baldness at that age.
Those who had lost hair from both the top of their head and their forehead appeared to have the greatest reduction in risk of prostate cancer.
The researchers concluded that early-onset male pattern baldness "was associated with a reduced relative risk of prostate cancer" in men involved in the study.
"Further research into a possible mechanistic link between these prevalent and androgen-related conditions is warranted," they added.
Dr Alison Ross, Cancer Research UK's senior science communications officer, commented: "Based on this small study, we can't say if baldness is really associated with a lower risk of prostate cancer, especially since previous studies have actually said the opposite.
"The results hinge on asking men between ages 40 and 70 to remember whether their hair was thinning when they were 30, which does not provide a very reliable measurement."