H.Baker: Fascinating! If you're going to include mortality, shouldn't you include the data suggesting that near-starvation ("CR") diets may improve longevity? I.e., I'm 6'0" and 165#, but I've been told by CR fanatics that I'd live a lot longer if I weighed 130-135# instead. (I might also run faster & climb hills on my bike faster).
--well, you probably won't live longer at 130-135#. The MetLife tables say you want to be 157-171 lb for minimum mortality. (The running and biking, maybe.) There is the slight escape hatch about correlation is not causality. For example, maybe if you are richer, you live longer, but then you also are fatter... whereas really, you'd live longer if rich & thin, so the metlife tables are deceptive. (I just made all that up, of course.) I would be interested to see if anybody else can cook up yet more hokey models that succeed/fail in predicting the correct exponents. Perhaps some other thermal model will do it, for example; I did not look into that literature much.