Force all fat people to become vegetarians.
I'm coming up on two years of being vegan and eating healthy, not to mention exercising regularily, and I haven't lost any weight (I've always been overweight).
It's not always so simple.
I was being sarcastic. There's plenty of junk that has no meat in it that'll make you fat. Drinking a liter of soda a day, 7 large bags of chips, a box of twinkies, and 2 gallons of ice cream a day won't help you lose any weight.
Definitely true.
But eating all that (except the bits that have dairy in them) probably isn't going to contribute to global warning, so it's a win!
Not exactly, it takes far more than 1 calorie of energy to produce 1 calorie of food. I don't recall the exact figure, but I saw it in a documentary. Consider the methods of production, packaging, and especially transport energy.
That's true, but livestock is considerably worse than other foods in terms of wasted energy, not the least because you have to feed the cattle, and it's something like 10 calories of food are fed to an animal to produce 1 calorie of meat (and, as you said, those 10 calories take more than 10 calories to produce)