I have seen many winning athletes posing for photographs biting their medals. I'm not sure why they're doing this. Do they suspect they're fakes? Or are they perhaps made out of chocolate? All I can think is that they're being inspired by Underdog.
As many people my age know, the TV series Underdog had a credits sequence where Underdog was shining shoes as his secret identity, and when he gets paid a coin, he bites it to make sure it's legit (which apparently it's not, because it bends in his teeth! Or maybe that's his super powers mangling good currency?). But there's a reason why Underdog might not be the best homage to reference at the Olympics. Can you think of what it might be? Why, yes: it's because Underdog uses an "Underdog pill" to get his super powers, which might make people think about doping, steroids, performance-enhancing drugs, etc.: not what I would think an Olympic athlete would want us to think about!
So whenever I see an Olympic athlete biting their medal(s), it immediately makes me think of Underdog, and that tell-tale "Underdog pill", and that reminds me of doping. Oops.