Twice in my life I tried to loose some weight, by starting my days with drinking lots of water, and just take a little notice of what I was eating. Worked well, but both times I also was pregnant within three weeks. (Being considered almost completely fertile)
Didn't dare to try again, and could not motivate myself for it either.
But, this morning I started with drinking lots of water. I'll keep you posted if I magically happen to conceive again.