Medically reviewed by Jay N. Yepuri, MD The Blue Poop Challenge tracks your gut transit time and can reveal some interesting secrets about your digestive system. The time it takes for food to travel ...

what they eat may affect the color of their poop. Undigested food in stool can also cause a color change. Unusual colors, such as green, may not signal a health issue. Stool color may vary briefly ...

Social media users have been posting pictures of vibrant-blue cupcakes with the unique hashtag #bluepoopchallenge. Yep, that’s right. Blue. Poop ... takes from eating food to excreting it ...