Too much alcohol can affect a man's performance in the bedroom - but the occasional pint of beer or glass of wine could actually improve male fertility and sexual function, according to a new study.
By contrast, drinking coffee and other caffeinated beverages makes men less likely to conceive with their partner, researchers found.
And another study showed that eating meat increases sperm density, compared to consuming a vegetarian or vegan diet.
Researchers presenting at the 70th Annual Meeting of the American Society for Reproductive Medicine in Honolulu, Hawaii, revealed the impact of various lifestyle factors on men's ability to conceive.
A group from the University of Rochester Medical Center in Rochester, New York, studied 753 men undergoing fertility treatment between 2003 and 2011, asking them about their drinking and smoking habits, as well as their sexual health and satisfaction. The average age of the men was 35.