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The fear that tighty-whities lower sperm count is a persistent one, it seems, based on the number of worried men who have asked data-crunching site FiveThirtyEight to verify whether it’s true.
Bad news for all those who enjoy this:
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FiveThirtyEight’s deep-diving into various fertility studies found that tighty-whities (and hot baths, saunas, electric blankets, extreme cycling, and warm weather) do have an adverse effect on sperm production: They make the testicles get too hot.
The good news is that after a few months of ditching snug briefs, sperm count returned to normal and men could resume wearing those tighty-whities with zeal. Still, they should keep in mind that normcore is very 2014.