Two studies presented at a conference in the US this week suggest that better diets make for better sperm: one compared a Western diet hight in red meat to one high in fish, vegetables and whole grains and found the latter was linked to higher sperm motility, and the second found that a diet high in trans fats was linked to lower sperm counts.

Dr Edward Kim, President of the Society for Male Reproduction and Urology, said in a statement:

“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 first study presentation, delegates at the 67th Annual Meeting of the American Society for Reproductive Medicine (ASRM) in Orlando, Florida, learned how an international team from the Harvard School of Public Health, University of Rochester and the University of Murcia in Spain conducted an analysis of data taken from the University of Rochester’s Young Men’s Study that recruited men aged 18-22 to fill in questionnaires about their diet and have their semen tested.

The tests took standard measures of semen quality, including sperm concentration, motility (ability to move properly toward the egg) and morphology (having the right shape to penetrate the egg).

In their statistical analysis, the researchers adjusted the results to rule out the potential influence of other factors such as race, smoking status and BMI. They then analyzed the men’s results according to two factors: those whose diets were high in intake of red meat and refined grains (the “Western” diet), and those with a more “Prudent” diet, with high intakes of fish, vegetables and whole grains.

The results showed that following a Prudent diet was linked to higher sperm motility, while sperm morphology showed no particular links with diet, and after the researchers adjusted for total calorie intake, neither did sperm concentration.

From the second study presentation, delegates at the meeting learned how researchers recruited men attending the Fertility Center at Massachusetts General Hospital to fill in food journals and agree to undergo semen tests. In this study, a subset of the participants also had their semen tested for trans fats.

The results showed that the higher the trans fats in the diet, the lower the sperm concentration. Such a diet was also tied to higher levels of trans fats in the sperm and the seminal plasma or fluid.

Written by Catharine Paddock PhD