The ninja led a hard life, and thirst and hunger were an inevitable part of the job that had to be overcome. But no matter how tough the ninja may have been he was still human, and that is where their secret herbal skills came in.
Two kinds of pill made by the ninja were “suikatsugan”, which temporarily quenched thirst, and “kikatsugan”, which relieved hunger. The main ingredient of suikatsugan was umeboshi (pickled plum), and those of kikatsugan were buckwheat flour and yams. These pills were almost like food, and although taking them for extended periods may have had undesirable effects, they would have been useful under certain conditions.