Gray stools are usually referred to as clay-like stools. A lighter, grayish stool may be due to the occurrence of a biliary obstruction. Jaundice refers to elevated bilirubin in the blood, causing yellowing of the skin and mucous membranes. Normal bound bilirubin is excreted from the liver cells through the bile ducts into the intestines, where it is broken down and reduced by intestinal bacteria into urobilinogen, most of which is excreted in the feces, resulting in the formation of color-coded stools, which are usually yellow in color. When the bile ducts become blocked (as is common with bile duct stones, bile duct cancer, cholangitis, etc.), bile or bilirubin is unable to pass into the intestines and re-enters the bloodstream, and blood bilirubin increases. The blood bilirubin increases. The bilirubin flowing into the intestines decreases, and the urobilinogen formed by bacterial decomposition and reduction decreases, resulting in lighter-colored stools or clay-like stools. Stools become gray, it is recommended to consult a doctor in time to clarify the cause of the diagnosis and standardize the treatment.