I didn't find that windows worked for me; I tend to overeat with that particular stricture. I guess anything I have to do every day is a problem for me...
5:2 has helped me be more in touch with actual hunger and to (usually...) eat based on that, not on calories, carbs, fat, etc etc etc. In fact, sometimes I get a little mad, because I find that I'm not hungry, but there's something yummy I WANT to eat, but don't feel that I can/should because I'm not hungry (I mean on normal days). So this is still a work in progress; I guess those naturally skinny people just DON'T EAT if they aren't hungry...bizarre.