Lots of links on the effect here.
There must be an adaptive aspect to that. It explains why body-builders and getting-in-shape exercisers (those who are not in the fat or overweight category, but just a little 5-6-lb pudgy with undeveloped muscles) need to force-feed themselves their five small meals (large snacks instead of "meals") daily to support their fitness-building. Over months, some of those fat pounds can be replaced by solid muscle pounds in other places.
Overweight people, on the other hand, have many weeks or even months of survival energy stores already on board and really only need several 30-gm doses of protein daily if they are embarking on a strenuous daily fitness program because body fat is a fine energy source. Certainly not three regular American meals/day if they want to get in fighting shape. We have discussed the various forms of eating (ritualistic, social/recreational, impulsive/emotional, false hunger, etc.) here.
In the first case and in the second, we see that subjective "appetite" can be a trickster for adults. I could build an analogy to sexual instincts, but I won't. Goals, logic, and discipline are powerful human tools. Perhaps our most powerful.
Side note: If you enjoy difficult fitness training, you have a problem. Like grammar school, you are supposed to hate almost everything about it. If you don't hate it, and if it isn't mentally and physically painful and aversive, try a new program. If you hate it, but feel glad you did it afterwards, great, because that is life's deal in most ways. If your daily life is strenuous physical work, you can ignore all of this.
