"A physician went to visit two patients. He saw that one of them was in mortal danger, therefore instructing the members of his household to, 'give him whatever he asks for.' He saw that the other was destined to live and said to them, 'He may eat such and such food, but may not eat other specific foods.' They asked him, 'Please explain why you say that the first person may eat any food he asks for while the second you say may not eat certain foods?"
The physician answered, "Concerning the one destined to live I said, "this eat and this you may not eat." But regarding the one destined to die I told them," Give him whatever he asks for, for he is destined to die anyway."
So, too, the Holy One Blessed be He, allowed idol-worshipers to eat swarming and creeping thing. but Israel who is destined to Life Eternal, he told , "Be holy for I am holy," so don't make your souls abhorrent."
Beside the spiritual benefit that this Midrash addresses, it is interesting to note that many
non-observant Jews as well as non-jews, as well, often go out of their way to buy kosher meat and food products, in the belief that they are healthier and of better quality. But is it so?
This issue is actually debated by the great medieval Jewish commentators.
The Rambam, explains in his Guide to the Perplexed (3:48), that "It is not the signs of a kosher animal which make it kosher, nor the signs of the non-kosher animal that make it non-kosher. These signs only serve to indicate which animals are permitted and which are forbidden. Rather, the reason that forbidden animals and fish do not have these signs is because they damage people's health. G-d knows of the injury that forbidden foods cause to man."
The Spanish commentator Abravanel, on the other hand, says, "Far be it from me to believe this, for then the Torah given by G-d is no more than a minor medical treatise, and this is not in keeping with its holiness and eternity. In addition, we ourselves see that other nations do eat these forbidden foods, and they not in any way affect their health. In addition, if the reasons were medical, then there would also be various plants which are harmful, yet the Torah does not forbid them...therefore, the Torah prohibits the consumption of non-kosher foods because of spiritual destructive effects that they have on a person's soul."
This approach seems to be consistent with the Gemara (Yoma 39a), which learns that the word "venitmeitem" (and you will become contaminated) Vayikra(11:43) also includes "venitamtem" meaning to be spiritually blocked. Rashi explains that this means becoming insensitive to the entire Torah experience. With respect to the eating of forbidden foods,the Sefer Hachinuch (Mitzva 73) notes that the harm caused by eating these foods is not physical. Rather they prevent a person from being able to 'tune-in' to the A-lmighty, His Creation and His Commandments - and to reach a higher spiritual level. For that reason the Rama rules that it is forbidden to give small children non-kosher foods (Yoreh Deah 81:7).
But what of non-kosher foods and medicines ingested not for nutrition or pleasure, but rather for purely medicinal reasons? Would they be permitted to be used internally? It is interesting to note, that in both the Chinese Materia Medica and pharmacopeia as well as The Rambam's Glossary of Drug Names, though most, perhaps 90% of the substances used do come from the vegetable kingdom, some most definitely are of mineral and animal sources.