According to a recent study published in the British Medical Journal men who drank alcohol "moderately"—that's five or more drinks a week—were found to have poorer sperm quality than those who drank less.
"Quality" was defined in the study as total sperm count and sperm size, among other factors.
The study looked at roughly 1,200 Danish men ages 18-28 who, besides their sperm quality, were otherwise considered healthy.
Drinking alcohol in the preceding week before the men were tested was also linked to changes in their reproductive hormone levels—testosterone levels rose while sex hormone binding globuline (SBHG) fell.
Researchers are wary to say just yet that alcohol consumption causes poor sperm quality because this is the first study of its kind. The findings could also show that men who naturally have lower sperm quality are more likely to drink more.
But, they left the bottom line at this: "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."
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