I know that there's people who are at least 100 years old or above in Japan, as their life expectancy is higher. The shortest answer is diet & portion sizes: since Japanese cuisine consists of seafood, rice, soybeans, and seasonal vegetables. Most portion sizes are controlled and turn out being smaller with a cultural practice of 腹八分 (はらはちぶん) or eat until about 80% full. (They opt for cold, green or hot tea rather than sodas).

There's universal health care coverage in Japan at least while in USA people stress about medical bills a lot. Exercise is incentivized in Japan via active movement (not as car dependent) from walking, cycling, and using stairs are built into everyday routines keeping people mobile into old age. That's the opposite of US since they're heavily dependent on "the car" as opposed to public transit, bicycles or walking on foot.