Fitness

So, I look at this bottle of lemonaid. 130 calories per 8fl oz.

That seems simple enough. But it's liquid. Why do the calories even metabolize at all? Why do they not simply get pee'd out? I understand with solid food, it's because your body takes the chewed up food, and puts it into your stomach, where it then decomposes.

But the liquid shouldn't even have time to decompose. It's liquid.

Also, I don't understand when you gain the calories. If I eat 3 of these snacks that say 100 calories, which is now 300 calories, do I gain the calories over the next few hours? Or is it delayed a day or two?

Because there will be days when I eat almost NOTHING, and then my scale says I gained 3 lbs. But then there's other days where I feel I ate like a slob, and somehow lost 2 lbs.

So I'm wondering if it's delayed as it decomposes.

Losing weight is hard, but it might be easier if I understood the rules of how this all works.

Also, do farts have weight? Like if I weigh myself, and then after that let out a massive fart, and weigh myself again, would there be any weight difference? Or is it just weightless air that FEELS like you're lighter afterwards?