Hm, my first post on the Carbo Canteen

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I personally will vouch for protein. For me. Oh, and fiber, love it. Once I added something like one whole egg and a couple of egg whites to my usual 1/2 cup of Fiber One w/ soy milk, I could get through the entire morning without starving (although I still make sure to eat a snack).
I also incorporate protein throughout the day, combined w/ complex carbs and maybe a little fat. I don't go VERY high protein, but I do pay attention now.
Have you tried experimenting w/ this over time? Perhaps this one morning you were just destined to be hungrier than normal, and would have been starving even if you ate your regular (which was?).
If you ever do a longer experiment than one meal on one day I'd love to hear how it worked out for you. Please don't take this to mean I think you were wrong in your initial assessment - it's my belief that our bodies are all so amazingly different and react differently.
I see your point about the added fat increasing satiety, but I have found the difference to be minimal (four egg whites instead of the one egg and two egg whites doesn't seem to increase hunger for me too much). Also, I recently read about new research that suggests fat is in fact not as satiating as commonly believed. I'll try to dig that up if I can. Personally I still find fat (controlling for it on it's own, not to contradict my first sentence in this paragraph) to have some satisfying effect, but perhaps it's mental and I just am glad I was able to fit a bit of yummy avocado or evoo into my calorie counts for the day

. Plus, I need the good fats regardless, so in they go.
FULL DISCLOSURE: I am a pescetarian, and really only occasionally eat the fishies, so I was skeptical of the whole 'eat more protein to lose/maintain weight thing.' But a stint on SBD, using mainly plant with some low-fat dairy/eggs as my protein sources, really moderated my view. I also am actively trying to lose the cubical-butt, so my eating habits are geared to the most nutritional bang for the calorie buck, without going crazy.