Constipation and drinking less water is related, constipation is due to a variety of reasons, summarized in the following aspects: 1, diet and bad habits, such as eating food is too fine, fiber food intake is relatively small, drink less water, less exercise and defecation habits are not good, all of these can cause constipation. 2, the pace of life changes, such as business trips to the field, these can cause constipation. The most important thing is that there are some big changes and blows in life, which can also cause constipation.3, and anal and rectal problems, if the intestinal tract has tumors or narrowing, these can cause constipation.4, can also be systemic diseases, which can also cause constipation, there are some patients with anxiety and depression, the application of anxiety and depressive drugs are also prone to cause constipation.