When a person feels full, there is no mitzva, not even an act of piety, to finish the food on his plate, even though whatever he does not eat will be thrown away. True, the pious are pained when food is discarded, and they would not waste even a mustard seed for no reason. If they can save something from destruction, they do so (Sefer ha-Ḥinukh §529). Still, since overeating is unhealthy, and bal tashḥit of the body is more serious than bal tashḥit of food that will be discarded, it is better for the food to be thrown away than for a person to eat it unnecessarily (Shabbat 140b). A person may likewise remove from his home unhealthy foods that he or members of his household may be tempted to eat. In times of poverty, it was better for a person to eat whatever he was given, so that he could build up reserves for difficult times. That reality gave rise to the practice of being careful to finish everything on one’s plate. Today, however, when even the poor generally suffer less from hunger than from obesity, it is better to throw away excess food than to eat it unnecessarily. The main care today must come earlier: one should not fill one’s plate with food one does not need, and should not buy unnecessary food in the first place.
A person who prepared a large meal and has a great deal of healthy, tasty food left over may not throw it into the garbage. Rather, he should keep it in the refrigerator or freezer to eat later. If his family alone cannot eat all of it, he should make an effort to share what remains with relatives or neighbors. If poor people would benefit from the food, it is especially praiseworthy to give it to them, thereby saving the food from destruction while also fulfilling the mitzva of tzedaka. Owners of banquet halls and restaurants likewise have a mitzva to give the good food they have left over to educational institutions or poor families. If the effort involved in finding people who will take the leftovers and bringing the food to them is worth more than the value of the leftover food itself, there is no obligation to do so, though one who does is considered especially pious. When it is difficult to find people who would benefit from the leftovers, it is an act of piety to give them to animals, such as dogs or cats, rather than let the food go to waste. However, if a person can use that time for something more important or beneficial, caring for the leftovers does not take priority. True piety means choosing the most beneficial course of action. [11]
[11]. The value of the effort involved in distributing food to the needy can be estimated by what one would have to pay one of the meal workers to handle the distribution. If that cost exceeds the value of the leftover food, there is no mitzva to go to the trouble of distributing it, since saving the food would mean wasting work time worth even more. If a person has free time, however, it is an act of piety to make the effort so that food and other useful things do not go to waste.
It also seems that even when the effort required to distribute the food to the needy is worth less than the leftover food itself, there are cases where no mitzva requires it. If the effort or awkwardness is so burdensome that he would be willing to pay the value of the leftovers simply to avoid the trouble of finding people to eat them, then distributing the food is not required; it remains an act of piety (see SA ḤM 263:1–3).
