The number of swimming sperm a man produces which broadly correlates with how fertile a man is likely to be, appears virtually unaffected by lifestyle choices, a team of scientists from Manchester and Sheffield universities has claimed, the Daily Mail reported.
"Our results suggest that many lifestyle choices probably have little influence on how many swimming sperm they have. For example, whether the man was a current smoker or not was of little importance. Similarly, there was little evidence of any risk associated with alcohol consumption," said Study leader Dr Andrew Povey, of Manchester University.
"This potentially overturns much of the current advice given to men about how they might improve their fertility," he said.
In the study, 2,249 men were recruited from 14 fertility clinics around UK and were made to fill out detailed lifestyle questionnaires. Information from 939 of the men who produced low numbers of swimming sperm was then compared with information from 1,310 who produced higher numbers, it reported.
The results, reported in the journal Human Reproduction, showed that men with poor quality sperm were 2.5 times more likely to have had testicular surgery, and twice as likely to be of black ethnicity. They were also 1.3 times more likely to do manual work, not wear loose boxer shorts, or not to have had a child before.
The study revealed that men's use of tobacco, alcohol and recreational drugs made little difference. Even being overweight, as measured by body mass index, did not affect sperm quality, it reported.
"So men should just take care of themselves, without feeling the need to become monks," said co-author Dr Allan Pacey, senior lecturer in andrology at Sheffield University.
However he cautioned, "Although we failed to find any association between common lifestyle factors and the number of swimming sperm, it remains possible that they could correlate with other aspects of sperm that we have not measured. These include the size and shape of sperm or the quality of the DNA."
