This sets up a bit of a false choice here. After all, we are programmed to feast. It is a survival mechanism that when we haven’t eaten for awhile and suddenly come upon food we voraciously over-consume, our bodies notifying us that if the past is any indication, there aren’t any regular mealtimes coming up soon- so eat up. But evolution has a built in tripwire. Our ancestors who came across putrid, bile-smelling carrion likely did not consume it. Others that did may have gotten a mild case of diarrhea, or maybe an intestinal infection, conditions that are benign with modern medicine, but altogether another matter in the pre-historic savannah. Those who didn’t have a gag-reflex triggered by the sight of maggots might not have made it to pass on their genes. Even if you were starving, the tradeoff of eating something that would make you sick, and dehydrate you might not be worth it. Restraint is just as evolutionarily necessary as indulgence is.