Good news, fans of sleeping in the nude: there is an excuse to air yourself at night-time.
According to a study in 2015 by the National Institute of Child Health and Human Development, Maryland, and Stanford University, sleeping in boxer shorts or PJs could damage sperm production and harm the chances of having a baby.
Tight boxers are the biggest offenders here – they increase the temperature of the testicles, which can cause the quality of a man’s sperm to decrease. Ditching them in favour of loose underwear during the day and nothing at night can bring about a 25pc increase in sperm quality, according to the research.
In truth, this is only the latest in a long line of scientific endeavour that suggests going commando at night really is the way forward …
You’ll get a better quality of shut-eye
Most sleep experts agree that wearing your birthday suit at night helps your body to regulate its temperature – which results in better, deeper, happier sleep. This is because your body temperature falls once you’re asleep; a process than can be disrupted by warming underwear or pyjamas (or your shirt and trousers after a night down the pub…).
You might lose weight
Seriously. If your body is too hot while you sleep, it won’t release much human growth hormone, which is the trigger it uses to repair cells. Instead, your cortisol (stress hormone) level will stay high, causing a night-time spike in insulin.
Effectively, your body remains in ‘panic’ mode rather than ‘healing’ mode, and chooses to store fat rather than burn it – which is why researchers at the University of Warwick found that insufficient sleep is linked to diabetes and heart disease.
You’ll look younger …
… or at least, you’ll age better. The same human growth hormone that helps you burn fat is also known as your body’s anti-aging agent. By repairing your cells, it helps to smooth over skin lesions, spots, and even wrinkles.
You’ll enjoy a happier love life
Ok, this one isn’t for singletons – but for those who share a bed with a loved one every night, going nude in the land of nod could result in a more content relationship.
According to one survey of 1,000, 57 per cent of nude sleepers reported being happier with their relationship, compared to just 48pc of clothing-clad catnappers.
Perhaps unsurprisingly, the key is believed to be in the skin-on-skin contact, which triggers the release of the ‘feel good’ hormone oxytocin. As a result, you feel happier, more connected to your partner, and – yes – more likely to be interested in sex.
You’ll dodge fungal infections
Whereas pyjamas or boxers promote the dreaded ‘sweaty nads syndrome’, sleeping in the buff helps to let your crown jewels breathe – which means you’ll be less likely to suffer from fungal infections such as jock strap itch.
“Keeping the area cool, dry, clean and “aired” at night will help to reduce the overheating that promotes this – especially in summer,” Dr Sarah Brewer told Mail Online earlier this year.
You’ll save money
Embrace nude sleeping and never again will you have that Autumnal sinking feeling when you reach for last year’s trusty PJs only to realise that they are just too fetid to be reintroduced into your daily existence.