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The Torah and Talmud claim (and I have Christian friends that also claim) that eating animals that

  1. are bottom-feeders or ruminants—That is, eat the crud off the sea-floor, like shrimp, or digest their own waste like rabbits, pigs etc.)—OR
  2. have a cloven hoof.

(but not both) is bad for your health.

  • Is there any evidence to suggest that because these animals consume "unclean" foods they are themselves unclean and therefore not fit for consumption?

  • Why would an ruminant animal with a cloven hoof be OK to eat, but a ruminant animal with any other hoof/foot not be OK to eat?

share|improve this question
Shrimp don't have cloven hooves. And in fact animals which are ruminants and have cloven hooves (such as cattle) are Kosher, while those with only one of these features (such as pigs which have cloven hooves but are not ruminants, or camels which are ruminants but do not have cloven hooves) are considered unclean. – Henry Apr 19 '11 at 11:25
This should probably be broken into two questions one about cloven hooves and the other about shellfish. While the claims come from the same source, the answers will have to address these two different foods distinctly. – Mark Rogers Apr 19 '11 at 14:13
According to some Jewish scholars, many of the "Kosher" laws make no actual sense at all, because their sole purpose is to test your obedience to god. The reasoning goes that following seemingly arbitrary rules requires much more commitment than following rules that make direct sense to you. – Lagerbaer Apr 6 '12 at 4:38
Carp is bottom-feeder and it's also traditional Jewish dish: – vartec Sep 10 '12 at 9:59
Dear Christian: please don't bump so many questions at the same time. You have practically taken over the entire first page! Any question posted just before yours will get almost no views. – GEdgar Apr 5 at 15:41
up vote 8 down vote accepted

Judiasm 101 has some interesting insights into Jewish dietary laws, although the author states,

However, health is not the only reason for Jewish dietary laws. Many of the laws of kashrut have no known connection with health. To the best of our modern scientific knowledge, there is no reason why camel or rabbit meat (both treif) is any less healthy than cow or goat meat.

I don't know how much I agree with that statement.

The basic tenets:

Certain animals may not be eaten at all. This restriction includes the flesh, organs, eggs and milk of the forbidden animals.

Of the animals that may be eaten, the birds and mammals must be killed in accordance with Jewish law.

All blood must be drained from meat and poultry or broiled out of it before it is eaten. Certain parts of permitted animals may not be eaten.

Fruits and vegetables are permitted, but must be inspected for bugs (which cannot be eaten)

Meat (the flesh of birds and mammals) cannot be eaten with dairy. Fish, eggs, fruits, vegetables and grains can be eaten with either meat or dairy. (According to some views, fish may not be eaten with meat).

Utensils (including pots and pans and other cooking surfaces) that have come into contact with meat may not be used with dairy, and vice versa. Utensils that have come into contact with non-kosher food may not be used with kosher food. This applies only where the contact occurred while the food was hot.

Grape products made by non-Jews may not be eaten.

There are a few other rules that are not universal. We may not eat animals that died of natural causes (Deut. 14:21) or that were killed by other animals. In addition, the animal must have no disease or flaws in the organs at the time of slaughter. These restrictions do not apply to fish; only to the flocks and herds (Num. 11:22).

Back to the camel/rabbit issue; both are carriers of diseases which can affect man. Since the aforementioned diseases would also affect various organs of the animals, they would not be considered edible under Jewish dietary law. Shellfish, clams etc - you can't see the organs of them to know whether or not they're clean - therefore they aren't edible.

My opinion:

As far as not eating something that keeled over dead one day... that should be a no-brainer, as is the case with carrion - rabies Since sanitation and food preparation left MUCH to be desired, foods which were 'risky' were banned, as were any animals known to commonly carry diseases which could affect men.

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Clarifies the rules but not the basis for them. Chickens carry diseases transmissible to people, but are kosher, for example. The question is whether the rules delineate some important health issue so kosher (or halal etc.) mark an independently verifiable biological/health distinction. – matt_black Jul 17 '12 at 10:29
How can this be accepted when it does not even answer the question? – Stefan Sep 10 '12 at 14:06
@matt_black Chickens carry diseases transmissable to people, most commonly salmonella (avian or bird flu in an unusual circumstance, so I exclude that). Over 30% of chickens carry salmonella. However, cooking chicken properly, until the juices run clear and there is no pinkness, kills the salmonella. Neither Jews nor anyone else eats raw chicken. This is just an isolated response to your particular comment. – Ellie Kesselman Nov 23 '12 at 22:47
@FeralOink I'm sure cooking bacon properly does the same. The question is whether diet rules about what you are allowed to eat work, not whether cooking works. – matt_black Nov 23 '12 at 23:01
This is an odd case where the accepted answer is not a valid answer to this site. This answer doesn't answer the question, it just cite what the rules for meat-eating are. The points that are not religion-based are opinion based or not referenced adequately. – Thales Pereira Apr 5 at 19:20

Bryna Shatenstein and Parviz Ghadirian did a great survey of adacemic research on the influences of diet on the health of different religious/ethnic groups. Here is a summary of their results (hopefully I am not violating any copyright laws by excerpting this!):

  • Mormons (Canada): "balanced diet" results in low mortality from "diseases of affluence" (Jarvis, 1977)
  • Seventh-Day Adventists (Japan): Low intake of broiled foods and antioxidant vitamins results in low incidence of digestive tract cancer (Phillips and Kuzuma, 1977)
  • Seventh-Day Adventists (USA): Prevalence of lacto-ovo vegetarianism leads to low mortality and low incidence of coronary heart disease, cancer, and diabetes (Phillips, et al., 1980)
  • Seventh-Day Adventists (Denmark): Prevalence of lacto-ovo vegetarianism and low incidence of tobacco & alcohol use resulted in a low incidence of tobacco- and alcohol-related cancers (Jensen, 1983)
  • Seventh-Day Adventists (USA): Low mortality among those who are lacto-ovo, higher mortality among those who are not (Kahn, et al., 1984)
  • Zen Buddhist priests (Japan): Traditional Japanese diet resulted in low mortality across the spectrum of all causes (Ogata, et al., 1984)
  • Seventh-Day Adventists (Japan): Lacto-ovo vegetarianism and broiled fish consumption resulted in overall reduced mortality (Kuratsune, 1986)
  • Seventh-Day Adventists (USA): Low mortality among those who have low meat and egg intake and high milk intake (Snowdon, 1988)
  • Old Order Amish (USA): General lifestyle resulted in low hypertension, low stress, and low circulatory disease mortality (Fuchs, et al., 1990)
  • Jat Hindus (India): Unclear if any medical/nutritional conclusions were made by this study (Kapil, et al., 1990)
  • Jews (Israel): Disparity between the rate of urological cancers between Jews and non-Jews linked to diet, although not necessarily a Kosher diet (Bitterman, et al., 1991)
  • Seventh-Day Adventists (USA): Low risk of coronary heart disease among those who eat nuts and whole wheat bread (Fraser, et al., 1992)
  • Buddhists (Taiwan): Vegetarian diet resulted in low plasma cholesterol, low glucose, and low uric acid (Pan, et al., 1993)
  • Ultra-Orthodox Jews (Canada): Low animal protein intake and the Kosher diet resulted in a high polyunsaturated:saturated ratio of diet fat, which has been shown to be correlated to low incidence of coronary heart disease (Shatenstein, et al., 1993)

To summarize, it seems like the people who avoid eating cloven-hoofed animals, bottom-feeders, and ruminants tend to also have a low intake of animal-based protein overall, which itself is healthy. Whether or not eating those types of animals would make one's diet worse, however, is a much more difficult question to answer.

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Actually, no. All they do is show (for the most part) that a low intake of animal protein is good for you on average. – Sklivvz Apr 20 '11 at 14:20
@Sklivvz, correct, however, that low intake of animal protein is associated with keeping Kosher (and thereby avoiding cloven-hoofed animals, bottom-feeders, and ruminants). – ESultanik Apr 20 '11 at 14:24
According to your linked studies, if I eat lamb 3 times a day (kosher, high protein) I will have a higher mortality rate than eating shrimp 3 times a day (which is a bottom feeder). Research gives exactly zero support to the particular religiously-specified selection. – Sklivvz Apr 20 '11 at 14:27
also, no causality is shown. – jwenting Feb 6 '12 at 6:53
And milk. The Seventh day Adventists show again and again that milk is not really that good for you. – fredsbend Apr 6 at 14:48

Shellfish do concentrate heavy metals and toxins so you could argue that they are bad for you. There is a relatively high rate of food poisoning from shellfish - but that seems to stem more consumption of them raw or undercooked, so the toxins are not being killed.

Worst of all from shellfish is the naturally produced Saxitoxin

With a result like that I'm surprised Puffer Fish weren't ruled out in the Torah and Talmud as well.

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Only fish that have fins and scales are Kosher (cf. Deuteronomy 14:9-10); therefore, puffer fish are not Kosher (they are all smooth and scaleless). – ESultanik Apr 19 '11 at 16:23
@ESultanik - ahh. I never knew that. Today I have learned something new :-) – Rory Alsop Apr 19 '11 at 16:33
Are you sure puffer fish don't have scales? Is there a reference? – matt_black Sep 25 '11 at 20:10
@matt_black this one at National Geographic do:-) – Rory Alsop Sep 25 '11 at 20:57
Would heavy metals and "toxins" (what does that mean, anyway?) be an issue for shellfish before the industrial age? Were there significant sources of heavy metals from natural sources or Bronze Age metallurgy that would make metal-laced shellfish a material risk? – Jon of All Trades Aug 22 '13 at 21:03

Rabbits do not "consume their own waste". You are probably thinking of their rather unusual two-pass digestive system. Rabbits are herbivores, and like all herbivores they have had to evolve a solution to the problem of extracting enough energy from plant material, which is mostly cellulose. On the first pass the food goes into the cecum, which is like a much larger version of the human appendix, where it gets fermented by bacteria that break down the cellulose. It then emerges from the anus as moist round mucus-covered pellets called cecotropes, which the rabbit eats. On this second pass through the digestive system nutrition can be extracted from the fermented plant material, and the remainder is excreted as black feces.

To us that sounds pretty icky, but its how rabbits have evolved, and although cecotropes come out of the anus they are not "waste" in any way.

If you eat only rabbit meat for an extended period you will probably be malnourished because rabbit meat is very lean, and you need more fat than it can provide. But if you can compensate for that with other sources of fat then it shouldn't be a problem.

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This doesn't answer the question. – Oddthinking Apr 5 at 17:54
The organs contain enough fat. Eat the liver and brain too and you'll be fine. – fredsbend Apr 6 at 14:50

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