How long does it take for food you eat today to show up in your weight?

Answer 1

Well, if you would eat a meal while sitting on a set of scales you'd increase a little as soon as you lifted anything off the plate. Some of that though would pass right through you w/o contributing to your net weight, and some of it would be used up by the continuous process of being alive. Basically it doesn't make sense to set a definite interval between when you eat something and when you gain/lose weight. It's a continuous process. As long as you're alive your body will be using up calories, and then every now and then you eat more calories. But while you're adding calories you're simultaneously using up calories as well. Because of this on-going nature the best way to track how your weight is developing is to establish a routine, like weighing yourself first time in the morning, and then compare the results over time.