I weight myself every one or two weeks just out of curiousity. Why would my weight go down as much as 5-6 pounds in a week and then come back up again the next week, even though I am fairly sure my normal routine is being followed?

Sometimes I eat more than others, but it is all about the same. What would cause this?

when you weight yourself, you should always do it around the same time of day, even if it's weeks apart ... you should always use the restroom before you do ... if you were sick anywhere in there, the limited consumptions of food would not be still in your intestines, which could easily be a good few pounds ... also, make sure you're not wearing shoes or other garments, and always use the same scale, one you trust ...

I always weigh myself on a monday and when I get up after being to the loo -but I never weigh my self around the time of the month as I know I will be heavier then and well think I have put on loads of weight and will get upset

But use the advice above

I use the same scales all the time - i have a bad habit with weighing myself every 4 days or so I know it is bad - and I have to stop - but I just need to know if I have lost any in that time you know. BAD BAD BAD HABIT

the last time i was on a scale was new year's when we had our finals in weight training ... i found it amusing to be on the scale every couple of days and note how many inches i was losing, but that i was gaining weight ... i've never really liked scales, 'cuz it always seemed i was on them when i was sick and had to go to the doctor, which usually meant i was REALLY, REALLY sick ...

I noticed when I use to weigh myself, I would do it in the morning one day then I would do in the evening a few days later. I noticed too that my weight was always different. Then I realized that I was heavier in the evening. So I started to weigh myself at the same time everyday.