Niddah 17a ~ Overnight Eggs and the Danger of Breast Cancer

THIS IS THE SECOND OF TWO POSTS FOR NIDDAH 17,

WHICH WILL STUDIED TOMORROW, SHABBAT.

*****

For a longer analysis of the evolution of the stringency of overnight eggs, see the essay published today on The Lehrhaus here.

Notice the OU kosher approval on the lower right.

Notice the OU kosher approval on the lower right.

In today’s page of Talmud we read a list of actions that according to the great second century sage Rabbi Shimon bar Yochai are liable to kill you. Here they are:

נדה יז, א

אמר ר"ש בן יוחי ה' דברים הן שהעושה אותן מתחייב בנפשו ודמו בראשו האוכל שום קלוף ובצל קלוף וביצה קלופה והשותה משקין מזוגין שעבר עליהן הלילה והלן בבית הקברות והנוטל צפרניו וזורקן לרה"ר והמקיז דם ומשמש מטתו

Rabbi Shimon ben Yoḥai further says: There are five actions with regard to which one who performs them is held liable for his own life, and his blood is upon his own head, i.e., he bears responsibility for his own demise. They are as follows: One who eats peeled garlic or a peeled onion or a peeled egg, and one who drinks diluted drinks; all these are referring to items only when they were left overnight. And one who sleeps at night in a cemetery, and one who removes his nails and throws them into a public area, and one who lets blood and immediately afterward engages in intercourse.

It is the first on the list, the eating of eggs or garlic that has been left peeled overnight, on which we will focus. At first blush you might think that this concern need not be taken seriously today. Imagine my surprise then, when I found it on the kashrut certification while flying from Israel.

From my airline meal insert….

From my airline meal insert….

“The eggs are not “beitsim shelau” - no “overnight” eggs.” This caused a wave of relief as a realized I had one less safety issue to worry about on the flight, but raised a series of other questions, not the least of which was what on earth were “overnight eggs” and why was I not familiar with this requirement? Well, mostly because it was not a kashrut requirement, until recently.

Overnight Eggs and the Jewish codes of Law

Although Rabbi Shimon bar Yochai considered the eating of overnight eggs to be life-threatening, his concern was a unique opinion in the Talmud. It was not codified as law by either Maimonides in his twelfth-century Mishneh Torah, nor the sixteenth century authoritative Shulchan Aruch, the Code of Jewish Law. It was mentioned here and there in a few rabbinic responsa, but they essentially ruled there was no need for concern. In fact it was all but ignored until it appeared in a work called Shulchan Aruch Harav that was first published in 1816. It was written by the first hasidic leader of the Chabad-Lubavitch dynasty, R. Shneur Zalman of Liadi (1745-1812) who is also known as the Ba’al ha-Tanya or the Alter Rebbe. “A person should not put cooked or other food or drinks under the bed because an evil spirit rests on them,” he wrote. “This applies even if they are placed in a metal container. Nor should he eat peeled garlic nor peeled onions nor peeled eggs that have been left overnight, because an evil spirit rests on them – even if they are kept in a sealed cloth. But if he left some of the root… or some of the shell they are permitted.”

The Shulchan Aruch Harav is of course of great importance to Lubavitch hasidim, but is perhaps less so to those outside of this community. The next step in the emergence of overnight eggs as a contemporary kashrut concern was a responsa by R. Yekutiel Halberstam (1905-1994). R Halberstam lost his family in the Holocaust, and rebuilt a new life in Natanya in northern Israel, where he led the Klausenberg hasidim (and built Laniado Hospital). In 1975 he wrote a long responsa (later published in his work Divrei Yatziv,) in which he could not be clearer:

The practice of being punctilious about not eating peeled eggs left overnight was widespread among our fathers and mothers. And when I set my heart to explain the issue, I noted that there are those among the later rabbis who issued a number of lenient rulings on the matter. But I will stand to defend the practice and to strengthen the customs of our ancestors, who were not lenient in any way about this.

The details are of course important, and R. Halberstam cites many works. If you take the time to read them, most actually demonstrate the very opposite of his conclusion. But what is of interest today is not the history of this belief. It is the claim made by R. Halberstam that eating overnight eggs causes cancer. Let me say that again. R. Halberstam claimed that there is a direct link between eating these dangerous products and cancer (specifically breast cancer, which is of course very prevalent in among Ashkenazi Jews, in large part due to the high prevalence of three breast cancer genetic mutations). Here is the editor’s note to Rabbi Halberstam’s responsa. The original Hebrew text is also shown below, for those who don’t believe me…

Overnight eggs cause cancer. From Divrei Yatziv, Yoreh Deah 1:31.

Overnight eggs cause cancer. From Divrei Yatziv, Yoreh Deah 1:31.

It is right to reproduce here what our teacher and author amplified in his holy talk given at a festive meal on Lag Ba’Omer 5736 [1976]:

I have sat and considered the cause of a number of terrible cases, which we learn about to our sadness, in which people fall ill to the well-known disease [i.e. cancer] God forbid, for which there is no cure… And after pondering the matter I have reached a conclusion, which my heart tells me is as clear as the day. It is because people are no longer cautious about not eating peeled eggs that have been left overnight in the way that they once wereIt is known that the nature of this disease [cancer] is because of growths within that spread and undermine the basis of human life and its continuation. And the rule of causation [that like causes like] explains the spread of this disease: since they are lax about this prohibition for various reasons. Similarly, other incurable malignant diseases are due to the evil spirit in these things. Perhaps this is what is hinted at in the Talmud when it uses the language “the fault is his...” [lit. “his blood is upon his own head.”] Immediately after eating [these eggs] it is already a certainty, and he is like a condemned man, God forbid. After eating they immediately cause damage to his organs. They may lay dormant for weeks or years, but they will ultimately strike him. Hence, from the first time he ingests them “the fault is his” It matters not whether they are eaten accidentally or deliberately, for in this respect they are like one who consumes a poison. It is therefore incumbent on everyone to be especially careful about this matter.

OVERNIGHT EGGS AND CONTEMPORARY US KASHRUT

Overnight eggs are addressed by both the Orthodox Union (OU) and the Kof-K, which provide kosher supervision for thousands of products in the US. Their conclusions are at best confusing. For example, the OU notes a permissive ruling from R. Moshe Feinstein, the author of Igrot Moshe. “This would provide a basis for certification of all commercial egg, garlic and onion products but would not permit a caterer to crack eggs for the next day’s breakfast or to cut onions and garlic for the next day’s salad. Others do not accept this approach.” The OU doesn’t explicitly declare its position, but it sort of does. You can buy overnight eggs that are OU certified (and parve). I did. They were delicious.

Kof K-1.png
Kof K-2.png

the Two magesteria of Science and Religion

In his Rocks of Ages: Science and Religion in the Fullness of Life, the late paleontologist Stephen J. Gould wrote of two magesteria or domains where one form of teaching holds the appropriate tools for meaningful discourse and resolution.

In the magisterium of science is "the empirical realm: what the Universe is made of (fact) and why does it work in this way (theory). The magisterium of religion extends over questions of ultimate meaning and moral value.These two magisteria do not overlap, nor do they encompass all inquiry…

We should ask scientific questions to the scientist, and meaning or moral questions to religious thinkers. That’s a pretty good way to stay out of trouble, and in fact is fully recognized in the Talmud itself. In a few days we will read the following:

נדה כ, ב

?אמר רבי זירא … דאמינא בטבעא לא ידענא, בדמא ידענא

Rabbi Zeira said … If I am not acquainted with the science of things, how can I possibly know about examining blood?

In other words, for Rabbi Zeira to opine about the religious status of a physiological process, he knew that he must fully understand it from a scientific perspective.

Here is another example of the same idea.In an unrelated incident later in the Talmud (Niddah 22b) there is a question about the origin of a uterine discharge. Notice the order in which things were asked:

ובאה ושאלה את אבא ואבא שאל לחכמים וחכמים לרופאים

- she came and asked my father whether she was impure. And my father asked the other Sages, and the Sages asked the doctors, and the doctors said to them.”

In fact this stepwise progression is mentioned twice -with the ultimate medical authority resting not with the rabbis, but with the doctors of the day.

Everything gives you cancer

In 2013 Jonathan Schoenfeld and John Ioannidis published one of my all-time favorite scientific papers: “Is everything we eat associated with cancer? A systematic cookbook review.” They noted the that dozens of foods or nutrients are associated with an increased risk of cancers. Did any of these published associations make any scientific sense? How solid were the conclusions, statistical significance and reproducibility of the literature that made these claims?

We selected ingredients from random recipes included in The Boston Cooking-School Cook Book...PubMed queries identified recent studies that evaluated the relation of each ingredient to cancer risk...

Associations with cancer risk or benefits have been claimed for most food ingredients. Many single studies highlight implausibly large effects, even though evidence is weak...
— Schoenfeld J and Ioannidis J. Is everything we eat associated with cancer? A systematic cookbook review. Am J Clin Nutr 2013;97:127–34.

In the chart below each dot represents a research paper that examined a food and its association with cancer. If the dot is to the left of the vertical line it reduces the risk of cancer. If it is to the right it increases it. Just look at wine on the first line as an example of the problem. There were nine studies; six suggested it decreased the risk of cancer (though they disagreed on the amount of that risk reduction) and three suggested it increased the risk. Coffee is even more muddling; the studies were evenly split, other than the one that found no relationship at all. It’s an embarrassing mess.

Effect estimates reported in the literature by ingredients. Only ingredients with >10 studies are shown. From Schoenfeld J and Ioannidis J. Is everything we eat associated with cancer? A systematic cookbook review. Am J Clin Nutr 2013;97:127–34.

Effect estimates reported in the literature by ingredients. Only ingredients with >10 studies are shown. From Schoenfeld J and Ioannidis J. Is everything we eat associated with cancer? A systematic cookbook review. Am J Clin Nutr 2013;97:127–34.

Be skeptical

Overall, “the vast majority of these claims were based on weak statistical evidence.” Individual studies reported larger effect sizes than did the meta-analyses, meaning that when the studies on a particular food were grouped together and reviewed as a whole, the was no effect on the rates of cancer. “Our findings support previous evidence” wrote Schoenfeld and Ioannidis “suggesting that effect sizes are likely to trend closer to the null as more data are accumulated.” The more research is done, the less there appears to be any effect at all between these foods and cancer.

I’ve worked in many different fields, and it’s hard to find another field that seems to be performing so poorly. It does draw amazing attention in the news, but nothing seems to be validated. I can’t think of any other field that has that constellation of failure.
— John Ioannidis. How Washington keeps America sick and fat. Politico 11/4/2019

This paper is a good reminder that not everything that is published in a peer-reviewed journal is certain (even if the authors think it is). As a reader it is best to maintain a stance of respectful skepticism. That is especially true about claims that a food causes cancer, whether those claims are made by a researcher or a rabbi.


For a longer analysis of the evolution of the stringency of overnight eggs, see the essay published today on The Lehrhaus here.



NEXT TIME ON TALMUDOLOGY: TALMUDIC PROBABILITY THEORY


Print Friendly and PDF