I assume you meant the health of the population? As far as I know, U.S. healthcare is the best in the world. Meaning the most advanced. Everyone who is anyone flies to the States for the level of advanced treatment not available anywhere else. If thay can afford it, of course.
Rolls Royce may be the best car, but sorry, I can't afford to have one. The difference between cars and healthcare is that I won't die if I don't choose to go bankrupt buying a Rolls Royce. One of the biggest problems with the US healthcare system is that many US citizens, even college educated ones with good jobs and insurance, can't afford to get sick.
EDIT: Major indicators of healthcare performance:
"Quality: The indicators of quality were grouped into four categories: effective care, safe care, coordinated care, and patient-centered care. Compared with the other 10 countries, the U.S. fares best on provision and receipt of preventive and patient-centered care.
Access: Not surprisingly — given the absence of universal coverage — people in the U.S. go without needed health care because of cost more often than people do in the other countries.
Efficiency: On indicators of efficiency, the U.S. ranks last among the 11 countries, with the U.K. and Sweden ranking first and second, respectively. The U.S. has poor performance on measures of national health expenditures and administrative costs as well as on measures of administrative hassles, avoidable emergency room use, and duplicative medical testing.
Equity: The U.S. ranks a clear last on measures of equity. Americans with below-average incomes were much more likely than their counterparts in other countries to report not visiting a physician when sick; not getting a recommended test, treatment, or follow-up care; or not filling a prescription or skipping doses when needed because of costs. On each of these indicators, one-third or more lower-income adults in the U.S. said they went without needed care because of costs in the past year.
Healthy lives: The U.S. ranks last overall with poor scores on all three indicators of healthy lives — mortality amenable to medical care, infant mortality, and healthy life expectancy at age 60."