I'm definitely biased by living in the southern hemisphere for almost half a decade. The places I've lived are visibly healthier than the US. People have less chronic health problems, take fewer sick days, etc.

I imagine a lot of that depends on where in the US you go. I live in an area that is statistically similar to Europe. If your idea of the US is south and east, it will be considerably different.

I've lived in major cities in the southeast and the west coast. The west coast of the US is still extremely unhealthy.

Learning how unhealthy the culture I grew up in is has been a gradual process. Shock moving to the west coast, and then shock at each of the subsequent moves around other parts of the world.