The scariest part of a Burger King’s Halloween Whooper doesn’t happen until after you eat it! The bun on Burger King’s A1-Halloween burger is dyed black, but eaters claim it goes in one color --- and out another color.

Turns out, something in the pitch black bun turns eaters stool into a horrifying bright green color. Sometimes for three days!

Social Media has been buzzing over the #GreenPoop. One person tweeted, it’s not even sickly green, like cartoon green. A comical green. Another tweeted she was done with food forever.

It’s unclear what ingredients in the Black Whopper turns stool into a St. Patrick’s Day celebration. Some think it’s the food coloring used to make the bun black. This seems like the logical explanation because certain green dyes are often used in black food coloring. However the company told ABC News that the black bun contains less than 1 percent food dye.

While most were shocked and scared about their green stool, others were are ready for another round of #GreenPoop. Hunter Stanton tweeted, “Took like three days for my poop to stop being green, but totally worth it.”

If you plan on searching the green poop hashtag, be very careful! As some individuals are posting visual images.

Thanks to this green stool debacle, Boris, Meat Sandwich, and myself have decided to make our own #GreenPoop challenge. We all plan on eating the Halloween Whooper today and will share our “results” on the air tomorrow morning. #Gulp

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