If you aren't getting enough water, you risk impairing these t wo functions to a certain degree.
Enough water insures that both digestion and metabolism are working at their optimum level.
By drinking six to eight glasses of water, you can help curb your appetite. Water can fill you up so that you don't overeat. It does the same thing for a variety of nutritional needs. For example, your body may need sodium, so it signals you to eat foods containing salt. But all you really need is the salt, not the additional calories in food.