Part of my husband's weight gain is water retention in his body. Yes, it isn't all the fats, but also water that made him big. We didn't realized it till he went to see our family physician. They did run series of tests and stuffs and the result was water in his body. And so, aside from advised to exercise and eat a healthy balanced diet, the doctor prescribed him a diuretic that would help him get rid of those excess water. Since we are into natural remedy and treatment, we thought of asking him if he could recommend something like natural diuretics, but didn't do it. We figured we can't find one online. Anyway, aside from diuretics, he needs to limit his salt/sodium intake for that contributes to water retention also. I remember I used to take diuretics, too at some point in time. It really helped a lot.