> Comparison data also showed that at every wealth level in the U.S., mortality rates were higher than those in the parts of Europe the researchers studied. The nation’s wealthiest Americans have shorter lifespans on average than the wealthiest Europeans; in some cases, the wealthiest Americans have survival rates on par with the poorest Europeans in western parts of Europe such as Germany, France and the Netherlands.

https://www.brown.edu/news/2025-04-02/wealth-mortality-gap

The US also have less healthy years.

> Just as in other countries, chronic conditions like heart disease are major factors in how many years Americans remain alive but in poor health. But, the authors add, a high burden of mental health and behavioral conditions — which the WHO groups together, and include depression, anxiety and addictions to alcohol and drugs — are also weighing heavily on our health span, as well as curtailing life expectancy in the U.S.

> Underpinning both chronic diseases and what are sometimes called deaths or diseases of “despair,” such as addiction, is the prevalence of loneliness, stress and inequality in the U.S., Gurven says. “It’s hard to avoid that living in a highly unequal society is stressful and that takes a toll on our health in so many ways,” he says. That inequality affects not only access to health care, but can also be seen in how little opportunity there is for Americans in many parts of the country to get physical activity or healthy meals in their busy days, helping to fuel the obesity epidemic, which, in turn, curtails health span.

https://www.yahoo.com/lifestyle/the-us-has-the-biggest-lifes...

Is there any reason you shouldn’t include the entire population?