During my recent trip to WCP, I lost eight lbs. and about an inch around the waist. That was weight that I really did not need to lose and I regained it quickly when I got back - in about the same amount of time that it took to lose it. Mostly the sugar was/is removed from my diet during trips and I believe that is the biggest factor for me. It's not the exercise or calorie burning that account for it since my day to day regimen at home is usually more intensive than a canoe trip. I do suspect that incomplete hydration may be a big factor too.