In research presented at a meeting of the European Society of Human Reproduction and Embryology, scientists found that obese men have worse sperm than normal-weight men.
The study were carried out by analyzing the sperm samples of more than 5,000 men in Scotland, and divided the men into groups according to their Body Mass Index. Men who had an optimal BMI (20 to 25) had higher levels of normal sperm than those who were overweight or obese.
Fat men had a 60 percent higher chance of having a low volume of semen, according to the research. They also had a 40 percent higher chance of having some sperm abnormalities.
The researcher also found other factors affecting men's sperm count: underweight men were just as likely to have the same problems as obese men, smoking, alcohol intake, history of drug abuse, and age.
The study also confirmed that "Male fitness and health are clearly linked to a man's fertility".
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