London, Jan. 11: The reason men die earlier than women could be because their hearts go into rapid decline during middle age, researchers have said.
Men and women have a life expectancy of about 75 and 80 respectively in Britain, with women over 60 the fastest growing group in today's greying society.
Now the largest study of the effects of ageing on the cardiovascular system has found that women's longevity may be linked to the fact that their hearts do not lose their pumping power with age.
'We have found that the power of the male heart falls by 20-25 per cent between 18 and 70 years of age,' said the head of the study, David Goldspink of Liverpool John Moores University.
'Within the heart, there are millions of contractile cells that enable it to beat. Between the age of 20 and 70, one third of those cells die and are not replaced in men... What surprised us is that there is very little loss of these cells in the female heart,' he added.
'In stark contrast, over the same period there was no age-related decline in the power of the female heart, meaning that the heart of a healthy 70 year-old woman could perform almost as well as a 20-year old's. This dramatic gender difference might just explain why women live longer than men.'
The university's research unit for human development and ageing studied more than 250 healthy men and women between the ages of 18 and 80 years, focusing on healthy individuals to remove the confounding influence of disease. The team has yet to find why ageing takes a greater toll on the male heart, said Goldspink.
Hormones may play a role but menopause does not seem to have a significant effect on the power of the female heart.
The good news is that men can boost the health of their heart with regular exercise.