The main reasons for yellow-brown stool are as follows, such as improper dietary structure, taking iron medication and a small amount of bleeding in the digestive tract. 1. Improper dietary structure: eating a lot of chlorophyll-containing foods such as spinach, oleaginous vegetables, etc., or eating a lot of blood products such as chicken blood, duck blood, etc., excessive chlorophyll or iron can not be completely digested and absorbed by the intestinal tract and discharged with the feces, resulting in yellowish-brown stools. 2. Taking iron medicine: iron in iron medicine can not be fully absorbed by the body, oxidized into ferrous sulfate and excreted with feces, resulting in yellow-brown stools. 3. A small amount of bleeding in the digestive tract: when a small amount of bleeding occurs in the digestive tract due to ulcerative colitis, acute and chronic gastritis, peptic ulcer, esophagogastric varices, digestive tumors, etc., the iron in the blood undergoes a redox reaction in the intestinal tract and is discharged in the feces, resulting in yellowish-brown or even brownish feces. It is recommended to go to the hospital in time to improve the examination when yellow-brown stool occurs, and carry out the treatment under the guidance of the doctor to avoid delaying the condition.