I would add that sometimes medication--if you're taking anything new--can cause a weight gain. Interestingly, my sister gained a bunch of weight years ago from various meds she was on for anxiety. She didn't to go off of them because of the side effects and ended losing all the weight and then some. I turned out that she's had Grave's Disease (hyperthyroidism) that has presented itself as panic attacks and the meds had masked the most obvious sign of the disease--rapid weight loss. If she hadn't gone of the meds, she would have eventually gotten even sicker. Kind of crazy!