Anyone can participate in ZOE's Blue Poop Challenge: By eating muffins baked with royal blue food dye, which turns your poop blue, you can track how long it takes food to travel through your gut.

Poop. Challenge. This didn’t start off as a viral ... The time it takes from eating food to excreting it is called the “gut transit time”. Researchers gave participants muffins dyed with ...

They eat up to 40 percent of their own poop. “If you stop them from doing it, they get vitamin B12 deficiencies — they get sick.” It’s something laboratory keepers have to watch.

It’s called a fecal shield. After eating nightshade leaves, the larvae produce toxic feces that they pile up on their backs. They carry it around, presenting a messy, distasteful and toxic ...