Scientists probably don’t conduct studies to promote chalupas as passive birth control. Still, young, sexually active men who want to do discourage their sperm from making them fathers may justify eating more fast food due to findings that junk food can lower the quality of sperm.

The Sun reports a study by Harvard University and a Spanish institution found that men ages 18 to 22 who ate a high amount of junk food were less fertile than others. Regardless of physical fitness, the poor eaters produced sperm that was less likely to survive on the way to egg fertilization.

A Japanese study also released this week found men who exercised moderately produce more durable sperm than those who didn’t. Rarely is there so much encouraging news for those who fear fatherhood and want to justify lounging around and munching fries.

Junk Food Makes Fit Lads Infertile [The Sun]

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