Characters are only allowed to heal after they've been attacked directly. It seems odd to watch one sit at 23 hp for 6 turns while there's 120+ pieces of cooked food available for consumption. The character in question did end up getting killed because of this aversion to eating.
Normal healing behavior has everyone eat after an attack so you only die from lack of food or multiple big hits. You spend your precious raid time gathering food resources and they don't even want to use them.