I don't know. If I'm not actively trying to lose weight, I usually have one day a week where I pay zero attention to calories. I'll eat a bagel with cream cheese for breakfast and also drink beer all day starting around lunchtime.  And then I'll probably eat something kind of shitty for dinner too. For me, it's Saturday or Sunday, but not everyone has the same schedule.  I don't know anything about this person's stats, but generally I think for normal humans, it really doesn't take that much restraint/effort to maintain a higher (but still normal) bmi of like 22-24.