You may retain it at first, but youi have to drink water to flush water, otherwise your body hoards it. Try lowering your sodium intake a little and do it for a week before you jmusdge how it is working. IIf you don't drink enough water while dieting, the liver has to do some of the work of the kidneys. The liver is the center of fat metabolism so if you are having it do the work for the dkidneys, it won't be metabolizing fat as efficiently.