Non sequitur. Your second statement does not follow from the first. First you state what medical care is not, then as an example, state something else medical care is not that appears unrelated to the first.

More constructively, saying that medical care cannot help with obesity is unnecessarily restricting the definition of medical care. Further, obesity is a factor in life expectancy, so measuring life expectancy is a reasonable proxy for measuring obesity, and to some extent, vice versa.

I responded to someone who attempted to show the quality of medical care in a country by looking at the countries life expectancy. The problem I pointed out is that many factors play into life expectancy with medical care being one of the many[1]. From what I have read obesity leads to many early deaths and people who are obese have a much higher rate of disease. The US is one of the more obese countries and is far more obese than Japan. The difference in life expectancy could be attributed to the poor general health of the citizens and not to any difference in medical care. In fact, with how poor Americans seems to treat their bodies it's amazing that many live as long as they do. Perhaps it's through access to much better medical care than available in other countries?

[1]Other life expectancy lowering factors that have little to do with the quality of medical care include murders. For example wikipedia states and [Japan] experienced 1.1 murder per 100,000 population, compared with 3.9 for West Germany, 1.03 for England and Wales, and 8.7 for the United States that same year.

In my (admittedly terse) response I was trying to say that medical care, or perhaps more appropriately health care, should include preventive care, such as obesity reduction. I suspect that health-related death has a much greater influence on life expectancy than accidents or crime, even if the US homicide rate is 8.7 per 100000, but would accept compelling evidence to the contrary.