The reasons for drinking more water during weight loss are as follows: 1, to prevent dehydration that may occur during weight loss, because fat in the process of decomposition will consume a lot of water, if too much fat decomposition and less water intake during weight loss, it is easy to dehydration. Therefore, during the weight loss period, the water intake should be increased appropriately to promote the decomposition of fat. 2, in order to prevent and slow down the occurrence of constipation, because the process of fat decomposition will aggravate the gastrointestinal tract peristalsis, and thus the intestinal rhythm will change, the chance of constipation will increase. In order to reduce and relieve constipation, during the weight loss period by drinking more water can reduce the occurrence of constipation.