Long-term travel requires a bit of flexibility. If you can work remotely, i.e., be a digital nomad, then going abroad is easy. Alternatively, anyone with enough travel funds and time off can plan on long-term travel.
The diets and lifestyles of citizens around the world are often better than ours here stateside. The food is more organic and fresh, there is less eating out and more cooking, and above all, there is more movement and exercise.