Five or More Drinks a Week Boosts "Useless" Sperm
Alcohol damages sperm quality in healthy young men, according to a new Danish study.
After analyzing medical records and sperm samples of men between the ages of 18 and 28, researchers found that weekly alcohol intake can seriously impair their reproductive prowess.
The study revealed that the average number of units drunk in the preceding week was 11. Two in three participants had binge drunk, and six in 10 said they had been drunk more than twice in the previous month.
While there was no strong link between sperm quality and recent alcohol consumption or binge drinking in the preceding month, the study linked drinking alcohol in the preceding week to significant changes in reproductive hormone levels. There was also a dose-response relationship, with sperm quality becoming worse with each additional alcohol unit.
Researchers said that sperm quality really started to deteriorate after five weekly drinks.
Participants who drank 40 units a week had 33 percent lower total sperm counts and 51 percent lower proportion of normal-looking sperm 51 percent compared to those who limited their drinks to five a week.
"This is, to our knowledge, the first study among healthy young men with detailed information on alcohol intake, and given the fact that young men in the western world [drink a lot], this is of public health concern, and could be a contributing factor to the low sperm count reported among [them]," researchers wrote in the study.
"It remains to be seen whether semen quality is restored if alcohol intake is reduced, but young men should be advised that high habitual alcohol intake may affect not only their general health, but also their reproductive health," they concluded.
The findings were published in the British Medical Journal.