Mollie is exactly right...during the night body fluids shift out of our cells and into the spaces in between cells...mine goes exactly like my wedding band snug in the morning (shake only), good during the day, and then too loose at night...my ring is slipping off and I have to have the discipline not to do the evening snacking while watching TV!!! I think since I am three years out this variabilty is the hardest thing about the band...