The breast cancer? Genetic. The longevity? Genetic. Dying earlier from unhealthy lifestyle? You guessed it, genetic! That particular genetic response is common

The breast cancer? Genetic. The longevity? Genetic. Dying earlier from unhealthy lifestyle? You guessed it, genetic! That particular genetic response is common to the human species. A person of a given ancestry has a healthy weight for their height, and exceeding it will shorten their lifespan on the average. Metabolism is genetic, though, no doubt about it. A different species might simply be unable to put on excess adipose tissue, eating too much would lead to purging from one or both ends. A different species might be cold-blooded. A different species might have an exoskeleton, which precludes obesity for mechanical reasons.