After working from home for 18 months during the pandemic, one of my worries when I returned to the office was if I would look different to my colleagues.

Not only did I earn a few more gray hairs, but I also gained a few more pounds.

I know I’m not alone. About 42% of American adults say they have gained more weight than they intended since the start of the pandemic, reports the American Psychological Association.

The drastic change in daily habits, comfort...