Ever since KF took me on a trip with started with a day and a half portage in deep woods I lose weight on every trip.  Evening meal is my biggest meal and many times I am just not hungry.  I still eat but end up eating less.  Over the past 5 years I have lost 5 to 10 lb on every trip and I gain a little over half of it back. I do notice I run out of energy late in the day on travel days.  My body has trouble with the foods that supply fast energy.  I should probably eat more for lunch.
MagicPaddler