Going Kosher – Dangerous Foods and Habits – Chapter 17

The Prohibition

1) The Torah commands us,[1] “Guard your life exceedingly”. Moreover, the rabbis taught us that the mitzvah of guarding ourselves against danger is stricter than the prohibitions of the Torah.[2] It is therefore a Halachic obligation to safeguard ourselves and remove any danger which may be life-threatening.[3] This being the case, it is incumbent upon us to be careful not to eat foods that are harmful to our health,[4] for doing so is a sin against body and soul.[5]

Fish and Meat

2) As mentioned above, due to health considerations[6] meat (including poultry[7]) and fish should not be consumed together[8] because this could lead to skin problems.[9] Nevertheless, they may be eaten one after the other,[10] provided that one cleanses his mouth by eating or drinking something.[11] However, for health reasons, one should drink something other than water after eating fish.[12]

Fish and Milk

3) According to Sephardic authorities, fish and dairy should, likewise, not be consumed together.[13] However, most Ashkenazic authorities differ and permit it.[14]

Disgusting Foods

4) It is forbidden to consume disgusting foods or beverages, such as food that has become soiled with vomit, excrement or malodorous saliva etc.[15]

5) Furthermore, one should not eat or drink from disgusting vessels, such as bedpans or glass medical vials used for receiving blood,[16] even if they are thoroughly clean.

6) One should not eat with filthy hands or on dirty plates because it is disgusting to do so.[17]

Dangerous Foods and Habits

7) All human sweat, except for facial sweat, is dangerous and should be avoided from consumption.[18] A person should, therefore, not carry unwrapped bread loafs under his armpit, as is commonly done in France, as they may likely become contaminated with sweat,[19] nor should he touch his armpit[20] with his hand. Of course, if this is inadvertently done, he should wash his hands.

8) Care should be taken not to put money, such as coins, in ones’ mouth. This is because money passes through many hands[21] and sweat[22] or dried spit from a contagiously ill person may be on it.[23]

9) Foods or beverages should not be stored under a bed,[24] even when covered.[25] However, if this was already inadvertently done, they may still be consumed.[26]

10) One should not insert a sharp object, such as a knife or razor, into a fruit[27] or vegetable,[28] lest someone fall or sit[29] on it and be fatally wounded.[30]

11) One should not drink water from a river at night,[31] even through a strainer,[32] because it is too dark to examine it. Moreover, one should not drink by placing his mouth directly to water flowing[33] from a hose,[34] even during daylight. Since it is impossible to properly examine it, he could come to swallow a leech[35] or the like. Similarly, when drinking water from a lake or river one should not drink directly with his mouth or by cupping only one hand. Rather, he should cup both hands so that he can properly examine the water.[36]

12) Before drinking water from a river,[37] one should pour a small amount of it out of his cup.[38] Furthermore, it should be poured by him rather than another[39] and this should be done before reciting the blessing, rather than after it.[40] There are two reasons for this; firstly, because it is a disgrace to the sanctity of the blessing to recite a blessing over something and then discard some of it.[41] Secondly, because by doing so he causes an interruption between reciting the blessing and drinking the water.[42]

13) One should never drink lukewarm water from a metal container,[43] unless something like spices, tea or mint leaves are added to it.[44] However, if the water is brought to a boil, it is permissible. On the other hand, if the water is in a ceramic or porcelain container, it is permissible to drink it lukewarm, even without spices, tea or mint.[45]

14) According to some authorities, one should not drink lukewarm water from a metal vessel nor should he drink lukewarm water that was heated in a metal vessel, even if it was transferred to a ceramic, glass or porcelain vessel. However, if the water came to a boil and then cooled to lukewarm, it is permissible to drink it, even if it became lukewarm in the metal vessel and even if he drinks it directly from the metal vessel.[46]

15) One should not drink water that stood overnight in a metal container, nor should he drink any other liquid that was admixed with water and stood overnight in a metal container.[47]

16) Likewise, one should not eat peeled garlic, onion or eggs that have stood overnight,[48] even if they are sealed. Nevertheless, if the hairy roots or part of the peel (or shell) remain attached, they may be eaten.[49] Likewise, if they were cut and mixed with other ingredients, such as a salad, pickled vegetables and oil, they may be kept overnight, even if the roots and peels (or shells) are completely absent.[50]

17) Eating and drinking while standing is difficult for the digestion and weakens the body.[51] Similarly, suddenly standing up immediately after eating and drinking a full meal[52] is dangerous and may cause fainting or even death if one is in poor physical condition.[53]

18) One should not drink the froth that forms on a beverage (such as beer), as this causes nasal mucus. Neither should one blow away the froth[54] or push it aside.[55] Furthermore, one should not drink a beverage from a bowl[56] nor cover a jar[57] with a bowl.[58]

19) Throwing breadcrumbs on the floor where they could be trampled upon or suspending bread midair brings about poverty. However, one may suspend meat or fish since this a standard way of keeping them.[59]

20) Moreover, eggshells should also not be thrown on the floor where they could be trampled upon, because this could lead to skin problems.[60]

21) Meat should not be sliced while being held in the hand as this could lead to injury.[61]

22) Just as it is forbidden to destroy any useful thing needlessly,[62] so it is forbidden to needlessly destroy or spoil any food or beverage.[63]

23) A person should not engage in conversation while eating, even to speak words of Torah or even to wish a person who sneezed good health, because this could lead to choking on the food.[64] Nonetheless, it is a mitzvah to speak words of Torah during a meal.[65] However, this should be done between courses[66] or before reciting grace after meals (Birchat HaMazon).[67] Today, many ignore this Halacha[68] but, as it says in Psalms,[69] “HaShem protects the simple”.[70]

24) One is endangering his friend’s health[71] by drinking from a cup and then giving him to drink from it.[72] Rather, he should clean the rim of the cup that his lips touched before giving it to his friend.[73] However, if there is cause to suspect that he may be suffering from a contagious illness, his friend should not drink from his cup, even if he cleaned the rim after drinking.[74]

25) Before washing Netillat Yadayim (נטילת ידים) in the morning, the hands of a Jew are impure.[75] Moreover, a person naturally fidgets with his hands[76] and may have unconsciously touched unclean parts[77] of his body.[78]  Therefore, it is very important not to touch any food[79] or beverage[80] before Netillat Yadayim.[81] Those who prepare the meals at home should be cautioned to be conscientious in this regard.[82]

26) A person should not eat from a pot that has not been used for thirty days (or more) without washing it before cooking in it,[83] even though it was washed after the last usage.[84]

27) Very hot meat which has just been taken off the fire should not be eaten until it cools somewhat.[85] The same principle applies to any food (such as bread) which is either too hot or too cold.[86]

28) One should not make a habit of eating the hearts of domesticated animals (such as cows, sheep and goats), undomesticated animals (such as deer, gazelles, and caribou) or even poultry (such as chickens, ducks and turkey), because it affects his memory.[87]

29) Nor should a person make a habit of eating vegetables, or any other food that has fallen from the table to the floor.[88]

30) It is dangerous for a person to see food and lust after it, but not eat it. The remedy for this is to spit out the saliva that forms in his mouth, rather than to swallow it.[89]

31) Partially baked bread should not be eaten because this causes a person to have difficulty concentrating on his studies.[90]