A recent study has suggested that wearing looser underpants could be a simple way for men to improve their sperm count and the hormones that control it.
In a study of 656 men, by researchers at Harvard TH Chan School of Public Health in the United States, boxer short wearers had a 25 per cent higher sperm concentration than men in tight-fitting underwear.
The experts, according to the BBC, said this simple lifestyle change could improve men’s fertility as cooler temperatures around the testicles improve men’s sperm count.
Scientists noted that sperm production was known to be sensitive to temperatures above 34 degrees Centigrade, which explained why the testicles hang down away from the body.
Some styles of underpants bring the scrotum nearer to the body, thereby causing the testicles to warm up, while others, such as boxer shorts, are loose and cooler.
In the largest study of its kind to date, the researchers found men attending a fertility clinic with loose-fitting boxer shorts had higher sperm concentration, a 17 per cent higher total sperm count and 33 per cent more swimming sperm than men with tighter-fitting underwear.
The researchers, however, noted that the sperm shape wasn’t affected and neither was the quality of the DNA.
They took into account other factors that can affect sperm, including age, body mass index and habits, such as smoking and use of hot tub, and speculated that the higher heat inside the pants was the root of the problem.
The study, which was published in the journal, Human Reproduction, also found that a hormone from the brain that tells the testicle to make sperm, called follicle stimulating hormone, was 14 per cent lower in wearers of loose underwear.
The findings suggest that this hormone kicks into gear when it needs to compensate for increasing scrotal temperatures and decreasing sperm counts in tight underwear.
A professor of Andrology from the University of Sheffield, Prof. Allan Pacey, who was not involved in the study, said the different levels of FSH among men with different types of underwear suggested that the tight-pant wearers had evidence of testicular damage.