Many of us think, “Oh this is really too bad for those poor animals,” but we don’t realize that the future of humanity is also at stake. In the backs of our minds, perhaps we unconsciously expect that humans will take over more and more of the planet, turning the earth into a giant farm to support humanity. The trouble with this vision is that we don’t understand ecosystems well enough to create an artificial ecosystem that can sustain itself. All viable ecosystems are natural, and all are enormously complex, especially at the level of bacteria. There has been just one attempt to create an artificial, enclosed and self-sufficient 4-acre ecosystem, and it failed spectacularly within weeks. Google “Biosphere 2”.

Yes! There’s never a longevity benefit from being fatter. There’s another explanation, too, for the paradoxical result of the BMI studies. It is that being congenitally stout does not hurt your health, but overeating does. So in our culture it happens that people with “fat genes” are very likely to be chronic dieters, especially women. People who are congenitally fat, but who keep their bodies within a normal range by dieting may have the best health statistics of all. This would agree with rodent studies.