Harvard study finds out how tight men's underwear affects sperm quality and quantity

This is the transcript of the video.

Briefs were introduced in the 1920s, well, boxers. This garment was dropped around the legs, giving boxers all the freedom they needed to move around the ring. And well, a decade later briefs arrived. They offered a more elegant and adjusted option, they also launched the classic question; Boxers or briefs? And it turns out that there might be a clear winner after all. Yes, wearing tight underwear can lower your sperm count.

You read that right: wearing tight underwear can lower your sperm count. It turns out that if the underwear is too tight, it pushes the testicles closer to the body, increasing the temperature in the process. And that's bad news for the sperm inside. A man's sperm production is at its best when his testicles are cooler than his core body temperature, 2 to 4 degrees Celsius, to be exact.

This is why the testicles hang down, away from the body in most mammals. So when you wear tight underwear, the resulting rise in temperature can harm sperm and potentially your fertility as well. Scientists have been studying this relationship between body heat and fertility for years, with several studies showing that men who work in high-heat conditions, such as bakers and pottery kiln operators, are more likely to have fertility problems than men. men working in “cooler” jobs.

But ovens are much hotter than the human body. So it wasn't until recently that researchers discovered that yes, even a small increase in temperature can cause problems. In 2018, Harvard researchers published the largest study on the subject to date. They analyzed 656 men seeking treatment at fertility centers and recorded their daily underwear preference: boxers, no boxers, briefs or briefs. To be sure, men who wore briefs had 33% more motile sperm, the kind that can swim and successfully fertilize an egg. They also had more sperm in general, about 25% more in the samples collected. But the researchers also found something they didn't expect. The men in the group who didn't wear boxers had higher levels of something called follicle-stimulating hormone, or FSH. FSH is released by the pituitary gland to help increase sperm production in the testicles.

Therefore, researchers think that an increase in FSH levels could be the body's way of compensating for low sperm production. And while both groups of men still had enough sperm needed to conceive a child, the researchers found that tight-fitting underwear could compromise the fertility of men already suffering from low sperm counts. Fortunately, young, healthy men tend to produce sperm continuously, so it's possible to reverse the damage caused by wearing tight underwear simply by switching to a less restrictive option.