Before the stool is very thick now more and more thin, pay attention to whether it is caused by changes in dietary habits, should also be alert to whether there are rectal lesions, such as hemorrhoids, chronic inflammation of the rectum, rectal tumors and so on. 1. Dietary habits: dietary intake if the previous reduction, or excessive intake of food containing high protein, high fat and lack of supplemental fiber, can lead to thinning stools. 2. Hemorrhoids: hemorrhoids can lead to narrowing of the anal canal, which in turn leads to thinning of the stool, and bleeding after bowel movements. 3. Chronic inflammation of the rectum: chronic inflammation can lead to the narrowing of the rectal lumen, which in turn leads to the thinning of the stool. 4. Rectal tumor: if there is a tumor in the rectum, the tumor will protrude into the intestinal lumen and press the feces, leading to the phenomenon of progressive thinning of the stool, and there can also be a change in defecation habits, bowel movements, such as the feeling of rectal stimulation phenomenon. Once the stool becomes thin, it is recommended to go to the hospital in time to improve the relevant examination to clarify the specific causes of the disease, to avoid delaying the condition.