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What’s the one thing you do everyday (and you do do it everyday, even if you claim not to) that makes you gain weight?

It’s farting. And yes, you do it everyday. You have to. You might not do it around other people, and thank you for that, but admit it. Farts are a part of life, and expelling methane is one of your body’s natural ways to eliminate waste products.

One would think that farting would actually decrease your weight—albeit by a very small, almost imperceptible amount. After all, a fart is a little bit of gas, and after it’s out of the body, it’s, well, out of the body. But this is not the case. It all has to do with the chemical makeup of methane. Methane is lighter than regular, ambient air. It’s also much warmer, and under pressure—both thanks to being inside of your digestive system. If you were to weigh yourself with a very sensitive scale, while farting, you would find that your weight increased by a small amount, about a few grams. That’s because you just let go of methane, something that is lighter than air.

Want more impossible questions? Check out Uncle John’s Impossible Questions.