A Harvard University School of Public Health study shows fish products help men's fertility, but bacon and sausage is more of a detriment, the New York Daily News reported.

Dr. Jorge Chavarro and his fellow researchers presented their findings Monday in Boston at the American Society for Reproductive Medicine's annual meeting. The study found white fish like cod and halibut were helpful to produce good quality sperm while processed meats did not.

"What brought up our concern is how meat is produced in the United States," Chavarro told the Daily News. "Many beef producers give cattle natural or synthetic hormones to stimulate growth, a few days or weeks before the animals are killed. We wanted to examine how these hormones might affect people who consume them."

The researchers analyzed more than 350 semen samples in 156 male participants who visited a local fertility center. The participants also answered a survey regarding their diet.

Those who confessed to eating red meat at least once a day were shown to have a negative effect on their sperm's cell shape and structure, or "sperm morphology." The study showed men who eat just one sausage link or bacon strip per day on average had about 30 percent less normal sperm.

"The relationship between diet and men's fertility is an interesting one and there is convincing evidence that men who eat more fresh fruit and vegetables have better sperm than men who don't," University of Sheffield fertility expert Dr. Allan Pacey told the Telegraph. "However, less is known about the fertility of men with poor diets."

Dr. Pacey acknowledged the difficult of accurately measuring the shape and size of sperm, but said eating fish instead of processed meat is good health advice no matter what.

"It is already known that high intake of processed meat is linked to other health issues and so advising men to limit their intake of processed food may improve their health generally as well as possibly be good for their fertility," he said.