The normal stool color should be dark yellow, mainly due to the amount of fecal bilirubin in the bile. Once the color of the stool changes, especially the phenomenon of clay color, most of them are caused by diseases of the liver and gallbladder. The liver is a particularly important organ in the body, not only for metabolizing toxins, but also for producing bile. Once the liver function is impaired, the secretion of bile by the liver will be affected. The lack of bile in food entering the duodenum not only causes indigestion, but also causes the stool to show its original color, which is clay, due to a decrease in fecal bilirubin. The bile secreted by the liver is mainly stored in the gallbladder, which contracts during eating and drinking to drain the bile into the duodenum. In the case of cholecystitis or gallstone disease, the bile excretion is affected and the bile cannot be excreted into the food chyme, so the stool will also develop a clay color.