Have you tried this in combination with low-carb intake? Insulin / blood sugar spikes and depressions can have strong effects on hunger & cravings. Also maybe trying to go 24 hours is too ambitious. Obviously YMMV but my current strategy is to skip breakfast and eat only eggs fried in butter when I find myself too hungry to bear it. Usually I end up eating only eggs for lunch sometime after 12 and then an ad libitum dinner around 6:30pm.

The low-carb might also be helpful in limiting your calorie intake. I find if I start eating carbs, I can basically just keep eating and eating them until my stomach is ready to burst. With high fat & protein items, I seem to reach fullness & satiety much faster and it lasts much longer.