While looking through photos of happy Olympians crying tears of joy on the podium, I noticed a strange pattern: They all bite their medals. At first I thought it was a coincidence, but after noticing athlete after athlete putting their newly awarded medals in their mouths, I suspected there was a reason behind the bizarre, celebratory habit.

Here's the deal: Because gold is softer and more malleable than other metals, one way to determine whether or not something is real gold is by biting into it — if it's authentic, your teeth will leave an indentation. Most medalists probably care far more about the symbolism of the medal than what it's made of; however, so why do we see everyone from swimmers to judo fighters to gymnasts pulling off this pose on the podium?

Because it's the money shot for the media pit. "It's become an obsession with the photographers," David Wallechinsky, president of the International Society of Olympic Historians, told CNN. "I think they look at it as an iconic shot, as something that you can probably sell. I don't think it's something the athletes would probably do on their own." He added that it's especially popular among swimmers.

Now I just feel sorry for Michael Phelps's teeth.

From: Good Housekeeping US