Cutting out sugar and useless carbs, and trying to replace those things with nuts and quality proteins - more nourishing and filling substitutes, can help a bit, I think. Mostly, try to stay away from refined sugar and products containing sugar or corn syrup. And for the love of God, lots more vegetables. Less dairy perhaps?

Get an apartment on at least the third floor, in a building without a lift.

Get a pet dog which needs to be walked several times a day.

Eat lots of chili peppers[0]:

"The analysis included data from more than a half a million people in multiple countries. When compared with people who never or rarely ate chili pepper, those who ate it regularly had lower rates of death due to cardiovascular disease (by 26%), cancer (by 23%), or any cause (by 25%)."

[0] https://www.health.harvard.edu/blog/will-eating-more-chilis-....

A little bit of high-intensity workout each week?

I know people who are incapable of eating lunch or any meal without a large can/bottle of full-strengh coca cola or such, ever single day. Most of whom complain about not being able to lose weight.

The science is pretty clear. Breaking out of old habits is much more challenging.

EDIT: Typos: whole -> whom, mean -> meal