Imagine taking 50 pennies and placing them in your mouth. Get them all up in there, lined against your gums. Put them on top of your tongue, so all your taste buds are covered. How does that taste? Terrible? Yeah, spit them out. Now imagine dealing with that residual metallic taste for two weeks. If you like pine nuts, that penny flavor could be in your future.

A phenomenon known as Pine Mouth is an intense metallic taste that affects a small number of pine nut eaters. According to the FDA, symptoms develop 12 to 48 hours after pine nuts are eaten and can last anywhere from two days to three weeks. Every time you eat or drink, the good old sucking-on-a-penny taste worsens, overtaking the flavor of any food you’re eating. Basically, Pine Mouth is hell for anyone who enjoys eating food.

A warning on the back of a pack of Trader Joe's pine nuts. Photo by Alex Lau

But what’s truly horrifying about this freak occurrence is that scientists have no idea what causes it. For a while, researchers thought that a Chinese variety of pine nut called P. armandii was the culprit in this crime against taste, but there’s no concrete evidence to tie a certain pine nut species or farming origin to the condition. The only concrete evidence that the FDA found was that Pine Mouth is a result of eating raw pine nuts. Which leaves us here, staring at the small warning on the back of the bag of pine nuts with a general fear and uncertainty.

There’s an unknown taste bud slayer roaming the streets, one that makes Jack the Ripper seem like a pretty nice dude. So please, be careful out there. Next time you’re about to order pesto or pignoli cookies, take a minute to think about the potential consequences. Are you a timid eater who would rather play it safe for self-preservation? Or are you the bold, pine-nut-obsessed diner who would take risks for that sweet, nutty, subtle flavor? There’s no wrong answer. You just have to know yourself.

Sticking to cashews might be a safer option: