Scientists have found that feasting on pizza, chips and crisps could make them infertile.

According to doctors from Harvard University and the University of Murcia nutrition can have a direct impact on the male reproductive system.

After analyzing sperm from men aged between 18-22 they discovered those who had a diet high in trans fats -- an ingredient found in most processed foods -- were at higher risk of infertility.

Before participating in the study, all 188 male volunteers were assessed to ensure no other health factors could affect sperm quality.

Food questionnaires were completed, and participant diets were put into two categories. These were “western” -- a diet rich in red meat, refined carbs, sweets and energy drinks -- and “prudent” -- a diet rich in fish, fruit, vegetables, and whole grains.

Semen tests were then conducted to assess sperm movement, concentration and shape.

Adherence to a prudent diet was associated with higher sperm movement, while the sperm of men with poor diets was found to be less likely to survive the journey to fertilize an egg.

Lead author of the study --presented this week at the Annual Meeting of the American Society for Reproductive Medicine (ASRM) -- Audrey Gaskins, said, “The main overall finding of our work is that a healthy diet seems to be beneficial for semen quality.”

"Specifically, a healthy diet composed of a higher intake of fish, fresh fruit, whole grains, legumes and vegetables seems to improve sperm motility...which means a higher number of sperm actually move around, rather than sit still.”

A second study working with 100 male volunteers led by Dr. Jorge Chavarro, at the Harvard School of Public Health, revealed that a diet high in trans fat had lower sperm concentration levels.

Trans fat levels found in the sperm and semen also increased.

Gaskins did stress however that despite the results more work is needed to explore the exact correlation between nutrition and fertility.

She noted, “This was a small study, and we don't know if there's something else about the men that causes them to have worse motility.

“We don't know if nutrition actually causes the change. So, for now, all we can say is that there's an association between nutrition and sperm quality."

Edward Kim, president of the Society for Male Reproduction and Urology said, “'We are still exploring the impact of nutrition on male fertility, but even these initial studies point to a link between a good diet and reproductive health for men.”

 From the October 19, 2011, Prepared Foods' Daily News.