I would have lost 5 lbs today. And I don't know what provoked the ferocity of the output (not true - touchy stomach and early-for-me [10:45 across town] doctor's appointment as a follow up to minor eye surgery 3 weeks ago meant I had cream of wheat for breakfast; leftover soggy Chinese chicken salad for lunch, followed by some chocolate pudding with milk, and another 4 oz of milk with vanilla wafers, and a big bowl of cucumber yogurt soup - all before dinner).
Interestingly, snopes (
http://www.snopes.com/fart-burns-67-calories/) dismisses this claim entirely, but it seems to me that if you are farting methane (CH4), rather than exhaling carbon dioxide (CO2), that means you didn't absorb the energy out of the food you ate, so there should be SOME negative caloric content attributed to a fart, via-a-vis the caloric content of the food you ate. Not sure how to count the calories though, since the energy content of food is mostly in the bonds between carbon atoms in fats, carbs and amino acids in protein, and both methane and carbon dioxide are both single carbon compounds.