Your brain is constantly eating itself. This process is called phagocytosis, where cells envelop and consume smaller cells or molecules to remove them from the system. Don’t worry! Phagocytosis isn't harmful, but actually helps preserve your grey matter.
Despite often being described as grey matter, the brain of a living person has more of a pinkish hue. Grey matter is the mass of neuronal cells that are involved in things like memory, speech and muscle control.