You've probably heard the old words of wisdom "Never eat yellow snow". While those words are indeed wise, there are a lot of other winter weather products that you shouldn't put anywhere near your face, too.

Take for instance all urban snow, which has been shown to contain a lot more pollution particles from exhaust fumes than is ideal. An experiment in 2016 showed that after just an hour of exposure, common pollutants had accumulated in the snow in a way that had "potential to influence human health" even if you don't directly put the forbidden slushie in your mouth.

Added to the list of wintery things you shouldn't eat is icicles. As similar to ice lollies as they look, meteorologist Katie Nickolaou has a warning for anyone tempted by them. 

The worst part is that she decided to give people the warning after people had already posted videos of themselves eating icicles to social media. 

"Please don't do that," she said in a TikTok video. "I'm a meteorologist, I should know. When icicles form, it's from water that melts off of your roof and runs down the side of the building."

So far, so gross. 

"Well, here's the thing: you know what else is on your roof?" she asked. "Bird poop. A lot of it. And that water picks it up and freezes it in the ice. You're eating poop."

Yes, rather than the delicious flavor you were expecting (plain), you will likely end up with a big mouthful of bird poop flavored ice, complete with sprinkles of whatever bacteria is in it. According to the UK government, should you breathe in any water droplets containing contaminated bird droppings you could put yourself at risk of psittacosis (a rare infectious disease caused by a bacteria associated with parrots and pigeons) or run of the mill Salmonella, which seems like a high price to pay for a lolly that tastes primarily of roof water.

In a follow-up video that we couldn't resist including, Nickolaou also busted the myth that you can kill someone with an icicle, ie the evidence will simply vanish as the ice melts away, ruining locked-room mysteries forever. To do this, she simply grabbed a colleague and proceded to stab her repeatedly with a large icicle to see if she'd die, which – spoiler alert – she did not.

Worryingly, she revealed this is a question she gets asked "all the time," so sorry to disappoint any potential murderers out there. Sincerely. If there's one demographic we don't want to disappoint, it's potential murderers.