On the whole it is probably better than US, but it's not like they don't have unhealthy habits either. Smoking is far more common than in most Western countries

On the whole it is probably better than US, but it's not like they don't have unhealthy habits either. Smoking is far more common than in most Western countries. Drinking I'm not so sure, but they do have the custom of forced work drinking parties, and most Asians have the gene that produce extra toxins from alcohol, so the harm from drinking must not be negligible. I would posit that the life expectancy is in part due to lack of documentation of dying. There are many cases in Tokyo where old people living alone are found dead only weeks later when neighbors complained about the smell.