Basically: eat boring food. I live in the USA but I grew up in Australia. The USA is big on highly rewarding food. Australia is too, but not to the level the USA is.
Whenever I go back to Australia, I will always lose 5-10 pounds without changing anything about my diet. It’s just less rewarding to our cave man brain.
When I come back to the USA, the weight comes back just as quick as it comes off.