Weight loss constipation may be due to insufficient fat intake. In general, weight loss caused by constipation may be caused by insufficient dietary fiber intake, insufficient fat intake, strenuous exercise and so on. 1. Insufficient dietary fiber intake: If you limit the intake of dietary fiber during the weight loss period, such as apples, celery, leeks and other fresh fruits and vegetables, as well as sweet potatoes and other coarse grains, it will lead to a significant reduction in the cellulose in the stool, resulting in dry stools and other conditions, leading to the occurrence of constipation. 2. Insufficient fat intake: fat on the human body not only plays the role of buffer, insulation, but also able to lubricate the intestinal cavity to facilitate the discharge of feces. When weight loss patients limit the intake of fat, it will lead to a decline in intestinal function, stool in the dry intestinal lumen is difficult to discharge. 3. Strenuous exercise: patients who lose weight through strenuous exercise, due to excessive water loss during strenuous exercise without timely replenishment of water, can also lead to dry stools, constipation and other symptoms. It is recommended to adopt a scientific way to lose weight to ensure the normal function of the body. If constipation persists after adjusting dietary habits, it is recommended to go to the hospital in time.