This is something I don't quite get about Jason Fung. He is critical of calorie restriction being less effective (he says you will feel more tired). But I'd like to see strong arguments and evidence for that.
[0]https://en.wikipedia.org/wiki/Minnesota_Starvation_Experimen...
He doesn't have to, as he is now at his target weight. He only needs to maintain his current body weight, which isn't the same thing.
A thin dude at work pretty much only eats junk food and washes it down with regular coca cola, of which he drinks 3-4 cans a day. Every single day. Doesn't exercise much either. And he doesn't gain weight. For me, god forbid I eat a single donut a week, I inflate like a balloon.