Unrestrained fatty foods and diabetes are perilous not only to men's waistlines, but to their sperm production as well.  As per a research done on 5,000 men in Scotland and presented on Wednesday at a meeting of the European Society of Human Reproduction and Embryology, scientists found that obese men produce worse sperm than their lean counterparts.

"Now we can also add poor semen quality to the already extended list accounting to the health hazards from being overweight," said Ghiyath Shayeb, the study's lead researcher at the University of Aberdeen.

But the experts weren't able to assert that the study done necessarily means obese men face major difficulties having children.

"If a man who isn't enormously fertile is involved with a normal partner who is fertile, her fertility will compensate," said Dr. William Ledger, a professor of obstetrics and gynecology at Britain's University of Sheffield, who was unconnected to the study.

In case both partners are obese, that could pose a serious problem, since obesity is known to decrease women's fertility, said Dr. William Ledger, a professor of obstetrics and gynecology at Britain's University of Sheffield, who was unconnected to the study.

Yet in a separate study conducted by Dr. Con Mallidis from Queen's University, Belfast concluded that diabetes may affect men's fertility by disrupting DNA in sperm. Once DNA is damaged, the quality of the embryo decreases, making it more difficult for an embryo to implant into the womb. This leads to higher miscarriage rates. Damaged sperm DNA is also linked to some serious childhood diseases, including cancers.

"Diabetics cause a significant decrease in the ability to repair sperm DNA, and once this is damaged, it cannot be restored," the study added.