Whether it’s a way for men to suit their look and appear more powerful in a modern society, or just a pervasive fashion statement, it’s impossible to deny that beards are totally in right now. And while today’s hairy-chinned trend is more rooted in style than practicality, it wasn’t always that way. In fact, back in the 1800s, beards were all the rage for a totally different reason: health.

According to British medical historian Alun Withey from the University of Exeter, beards were actually prescribed by doctors as a remedy for common ailments such as sore throat, and were thought of as natural air filters. Though this sounds ridiculous to us today, there’s actually some pretty sound reasoning behind the hypothesis that would have made a lot of sense back in the 19th century.

As Colin Schultz explains for Smithsonian Magazine, germs were a relatively new and scary discovery. Imagine going your whole life without fearing airborne germs – it’s nearly impossible today. After all, our fear is why whole markets for antibacterial soaps, sprays, and other household cleaners popped up and remain happily in business, despite the lack of scientific evidence that they actually work.

Well, for those living in the Victorian era, the 'germ theory of disease' was gaining notoriety, and members of the public were suddenly faced with a barrage of news headlines telling them that deadly, invisible germs were swarming all around them. It's more than enough to cause a bit of a panic, and with panic come weird ideas.

So, with more and more patients coming to doctors for help against germ-related illness, some physicians got the bright idea to tell men to grow out their beards to filter the air around them. They also claimed that facial hair might help filter other toxins, such as coal dust and the general filth that was 1800s living. This combination of germ-fighting and air-filtering led many men down a path of bearded glory.

Now, it’s important to point out that beards were probably popularised for other reasons, too. But doctors were certainly adding fuel to the fire. We know today that simply having hair on your face is not enough to protect against germs, and that germs are not inherently bad for you (some are vital to our existence), but any option was a good option back when germ theory was first making its way into the public consciousness.

The funny thing is, according to Lauren Friedman at Business Insider, beards can actually be less hygienic than a shaved face. "One recent study in Behavioral Ecology points out that "hair on the face and body are potential localised breeding sites for disease-carrying ectoparasites," she reports.

But this is at odds with another recent study published in the Journal of Hospital Infection that looked at samples taken from 408 hospital staff. As David Nield reported for us back in January, the data showed that the clean-shaven staff members were more than three times as likely to be harbouring methicillin-resistant staph aureus (MRSA) on their skin - a particularly notorious source of infections in hospital - than the bearded ones.

Beards weren’t the first or most ridiculous treatment people believed in before science could catch up to public outcry. In the 1700s, doctors literally thought blowing smoke up someone’s butt could revive them, especially for drowning victims, and during the Middle Ages, people reportedly kept farts in jars to ward off the plague.

As our understanding of germs increased and society as a whole got a lot cleaner, doctors adjusted their approach to germs, eventually getting to where we are today. The beard prescriptions were more of a result of mass panic than any sort of scientific understanding, but it’s interesting to look back and see just how far we’ve come.