When the day comes that you want kids—a long, long time from now, of course—you’ll want your swimmers in Michael Phelps-shape, right? Then drop that donut. Two new Harvard studies show that diet can significantly hurt the quantity and speed of your sperm.
In one study, researchers found that men with the lowest trans-fatty acid intake had roughly double the average sperm concentration as other men—79 million sperm per mL compared to 48 million among those with the highest intake of trans-fatty grub.
More research is needed, but it’s possible that trans fats may accumulate in sperm and wipe them out over time, says study author Audrey Gaskins, a Ph.D. candidate at the Harvard School of Public Health.
