What do dark and soft stools indicate?

Lots to consider...: Color & texture of stool varies with foods, speed of emptying of the GI tract, medications & supplements ingested, gut flora (unique for each individual), additives (like blood), subtractions (like absent bile), infection, inflammation, & other factors. More importantly, if stool appearance is unusual for you & persists, or is accompanied by alarm symptoms, then medical evaluation is in order.