Why is poo usually brown?
The brown colour of poo comes from the iron in red blood cells from your liver and bone marrow, which turn brown in the intestine. However, not all poo is brown, in fact some illnesses can turn poo yellow or green, and some foods can even change the colour of your poo. Eating loads of beetroot can your poo red, and some food colourings can change the colour of your poo, even to blue!
