I often find myself doing this arithmetic in reverse, as I'm working out at the gym. You watch that calorie counter on the exercise machine and you realize how easy it is to eat excess calories, way in excess of how much we burn off each day in our typically sedentary lives. Thinking about how many minutes I need to work out (a LOT) to burn off an extra candy bar is one of those mental tricks that helps me hold that resolve to avoid unnecessary snacking with junk food or to eat out sparingly.

That take out order from your favorite fast food or quick service restaurant could be over a 1,000 calories. Is it any wonder that we have so many obese folks? It's cheap, it tastes good, it's convenient--we're just addicted.

Then think about a show like The Alaska Experiment. The cast members are all weak, shaky, nauseous, light headed, passing out after switching from their typical American diets to a situation with limited food. Gee, sounds almost like withdrawal symptoms, don't you think???

Blast, are you thinking more long term for this particular post, or short term? Foraging could be considered less crucial in a shorter term situation, like getting lost. Although any food would be helpful and would help spare your body from consuming lean tissue over time and hopefully take the edge off the low blood sugar symptoms I mentioned above, unless you're actually using up a lot of energy trying to forage in the first place.