Every one must study his own nature. Some of you can sustain life with less food than others can, and therefore I desire that he who needs more nourishment shall not be obliged to equal others, but that every one shall give his body what it needs for being an efficient servant of the soul. For as we are obliged to be on our guard against superfluous food which injures body and soul alike, thus we must be on the watch against immoderate fasting, and this the more, because the Lord wants conversion and not victims.
~ Francis of Assisi