Why is my weight fluctuating so much?

I have changed my eating habits and joined a gym in an attempt to lose weight and maintain a healthy, fit body.

I started off at 155 lbs a few months ago, but really didn’t start losing weight until recently.

On Saturday morning, I weighed in at home at 144 lbs. I had a personal trainer session on Thursday afternoon and he weighed me at the gym – 152 lbs. I weighed myself again at the gym after a long workout Friday night – 156 lbs. I knew that had to be wrong, so I came home and weighed myself there – 152 lbs clothed, 148 lbs naked. This morning was my official weekly weigh-in, and the scale read 143 lbs.

Now, please don’t tell me to stop obsessing about the scale and please don’t tell me to stop weighing myself so often. I only weigh myself once a week and I’m very aware that how I look and feel is more important than a number on a scale. The training session just surprised me, so I wanted to see what my weight would be throughout the day. I’m not upset by it, just curious.

They say your weight fluctuates 2–5 lbs throughout the day. I do drink a bit of water, but I’m not eating a whole lot so I figured I’d fall in that range, but how could my weight fluctuate 13 lbs from morning until night? Is that normal?

BQ: Do you find that your scale at home gives you the same weight as a doctor’s scale? I usually weigh about 5 lbs more at the doctor, even if I haven’t eaten. I thought my scale was just off, so I switched from a digital to the old-fashioned kind that requires no batteries and I’m getting the same results.