Fasting - Has Anyone Else Had This Experience?

In my last post I reflected upon the value of fasting.  I also admitted that I have rarely practiced fasting outside of the Church's prescribed days.  In the past couple of months however, I have fasted for part of the day - small breakfast, skipped lunch, and then had a big 'ole dinner.  Here is something crazy that I've noticed though, and I would love to hear if anyone else has experienced it:  If I miss a meal in the course of a usual day - as when I forget my lunch at home - then I feel absolutely famished.  But if I tell the Lord that I am going to fast from lunch, then the hunger pains or either light, last for only a brief time, or simply never come.

I notice this on Ash Wednesday and  Good Friday too, when we fast for the entire day - the hunger is never as bad as I had expected.   Is there something psychological at work here?  When we are deprived of food against our will, we pine for it; but when we make an intentional decision to abstain from it, we don't hunger as greatly?  And if that is the case, then why do I experience hunger so strongly when dieting?  Does offering the hunger as prayer somehow change the psychological/physical experience?