120 extra calories a day is an extra 12 pounds a year. Combine that with your metabolism slowing down as you age and as the years pass you might find yourself expanding.

Also, the amount of oil you avoid by moving from deep frying to air frying, depending on portion sizes, can be much more than a tablespoon.

(Obviously, metabolism is more complex than this. I'm discounting the effects of adding fat on satiety, absorption rates, etc.)