Why Genetically Modified Foods Should Not Be Considered Kosher.

New technological innovations have always created a need for the Jewish community to respond from a religious, ethical and cultural perspective. For instance, the discovery of electricity forced Jewish authorities (rabbis) of the past to assess its use on Shabbat. Hence, we have hot plates and crock pots running but no switches flicking. The time has come for Jews and Judaism to take a serious look at perhaps the most fundamental innovation of our time, the genetic manipulation of life. Genetic Engineering (GE), and the Genetically Modified Organisms (GMO’s) it has been used to create, are incompatible with some of the most basic and fundamental tenants of Jewish beliefs and values. To this point in time, the issues of GMO’s in general, and GMO’s in human food in particular, have been largely ignored by the Jewish community.

Problems with Current OU stance

Wondering what the “official” opinion was of the Jewish community, I turned to the Orthodox Union, who I hoped would be able to shed some light on this question. Their FAQ’s website http://oukosher.org/index.php/learn/article/genetically_engineered_food/ states that,

“There are two dimensions to this issue. First, there is the health concern. Is it safe to consume genetically altered foods? This question is presently a matter of great public debate. Where does the OU stand on this question?

In Jewish Kosher law, a person is not permitted to eat food that is detrimental to one's health. Nonetheless, the OU views the determination of whether or not a particular substance poses a health danger to be outside of the realm of its expertise. This issue is not in the purview of a kashruth organization, and should be decided by responsible government agencies and health professionals. In practice, the OU would generally agree to certify a product that the USDA considers to be safe. The presence of an OU symbol on a product should not be misconstrued as an endorsement of the safe status of a product, since, as stated, we view this matter to be outside our domain. "

In other words, kosher does not mean “fit to eat” and a kosher sign does not mean that a product is safe. If the OU is not qualified to make judgements on food that is detrimental to one’s health, then we must make those decisions for ourselves. This means that we as Jews must look beyond the OU symbol and look for an Organic Symbol or other GMO-Free certification (organic foods are not allowed to contain GMO’s, per the USDA’s current regulations). What’s the point of the OU symbol then, I was left to wonder, as I turned to the second dimension.

The second issue is as follows. If non-Kosher genetic material is introduced into a Kosher product, does that render the genetically altered material as non-Kosher? For example, if a new strain of tomatoes is developed by introducing genetic material from a pig cell, is the tomato a Kosher entity?

In our opinion, the genetic engineering does not affect the Kosher status. This is the case for two reasons: Firstly, the genetic material is generally microscopic and is not significant enough to change the Kosher status. Secondly, the generic material is only introduced in the initial stage. Subsequently, the genetically altered item produces new offspring, which has not been the recipient of non-Kosher genetic material. The presence of a non-Kosher gene in a tomato does not render as non-Kosher all subsequent tomatoes that are “descendents” of the genetically altered tomato.”

The OU here misses the point completely. Genetic manipulation might be small in size in terms of the genes involved, but the implications are nothing short of huge. Think of fish that could be engineered not to have fins or scales (would they then be kosher?) or pigs engineered to have cloven hooves. In fact, there is a petition currently pending at the FDA that would allow genetically modified salmon into the food supply. These salmon have been genetically engineered to contain the gene of an eel in order that they will grow to market weight more quickly. Eels, however, are not kosher animals and therefore the question is not at all hypothetical as to whether these salmon would be kosher. Not to mention that kosher animals that are fed GMO foods (currently common practice) are less likely to be kosher at the time of slaughter, given their higher rates of organ defects and succeptibility to disease that would preclude an animal from being considered kosher.


Other Jewish Responses to the question of GMO's

Being frustrated with the OU’s ignorance of the issue, I researched other Jewish views on the issue. To the extent that the issue of Genetic Modified Organisms has been examined by Jewish legal scholars, the conclusions have been, “fraught with problems” http://www.biomedcentral.com/content/pdf/1472-698X-9-18.pdf

While some sources allow GE as permissible only “if they are not directly prohibited by God and if the research will benefit mankind.” Others allow GMO’s only on the qualification that they “save and prolong human life as well as increase the quality or quantity of the world's food supply.” However, the use of GMO’s has done anything BUT benefit mankind. Instead, it has unleashed a Pandora’s box of harm into the environment.


The mixing of two unlike species is a Jewish prohibition called Kil'ayim (Hebrew lit. "Mixture" or "Confusion") is the prohibition of crossbreeding seeds, crossbreeding animals, and mixing wool and linen as described in Leviticus 19:19 andDeuteronomy 22:9-11.

Kil’ayim is connected by some with the sins committed during the times of Noah, where the earth and all flesh upon it were punished “for all flesh had corrupted its ways upon earth, all men and all animals.” This corruption involved the mixing of species that were not intended to mix. In the last couple of years, scientists have crossed the dangerous line of creating laboratory animals with human DNA-developing mice and sheep with human livers, hearts, and brains. According to scientist, Paul Elias, “The biological co-mingling of animal and human is now evolving into even more exotic and unsettling mixes of species.” We should not repeat the sins of Noah’s generation by mixing species, neither should we repeat the sin of Babel by putting human ingenuity above divine will.

Health Issues

Another basic tenant of Judaism is the holiness and sanctity of life. The idea of Pechuach Nefesh, or the preservation of life, holds that life is holy and therefore we should be preserve our health and protect our life.

The science is clear that GMO’s are bad for health. Numerous animal studies show GMO’s cause such health problems as reproductive disorders, birth defects, kidney and liver malfunction and more. http://www.truth-out.org/1215091 and also http://www.aaemonline.org/gmopost.html The reproductive harm caused by ingesting genetically modified organisms http://english.ruvr.ru/2010/04/16/6524765.html contradicts G-ds first commandment to mankind to, “be fruitfull and multiply.” The precautionary principle (from both a scientific and Jewish perspective) says that we should err on the side of not utilizing new technology when the science is inconclusive or missing. Labelling is necessary if one were to chose to follow this path, yet foods in the US are not required to bear labels stating whether they are produced with GMO’s or not. Given the numerous health dangers associated with GMO’s the Jewish community needs to speak up and demand labelling of Genetically Engineered foods, so that they can avoid these numerous detremental effects.

Arguments in favor of GMO's are based on lies

Proponents of GMO crops make two main claims in support of GMOs. The first claim is that GMO crops result in higher yields per measure of land, thus reducing the amount of land needed to feed the world’s population. The second claim is that GMO’s require the use of less herbicides in their production, and thus keep the costs and environmental degredation and levels of toxic runoff down compared to non-GMO crops. Both of these claims are absolutely false.


“Debate in the U.S. was triggered by and persists because of claims by the biotechnology industry, farm groups and proponents of biotechnology that RR soybeans actually have reduced herbicide use on the order of 20 percent to 30 percent. These claims are false and can be traced to Monsanto-funded, proprietary studies employing biased analytical methods, as documented below. The impact of Bt corn and cotton on insecticide use is mixed. Bt cotton has reduced insecticide use in several states, whereas Bt corn has had little if any impacts on corn insecticide use. From an environmental perspective in the U.S., Bt cotton is the only legitimate “success story” among today’s GMO crop varieties.” (http://www.biotech-info.net/first_generation_GMC.pdf Page 15).

And even Bt cotton has failed in many places, including devastating cosequences in India, where thousands of farmers have been committing suicide every year as a result of failed crops and the resulting high indebtedness.

GMO's cause widespread environmental destruction

GMO’s cause other forms of environmental destruction as well, including destroying soils and soil micro-organisms.


Hence, once GMO crops are planted on a piece of land, that land becomes degraded and sterile, rather than life-giving and fertile. GMO’s also result in the deaths of pollinators such as honey bees and butterflys. http://www.globalresearch.ca/index.php?context=va&aid=16747 For people who value land that flows with “Milk and Honey,” the demise of the honey bee ought to be of great concern to Jews worldwide. The lack of pollination for fruit, nut and other crops carried out by these species likewise will have dire consequences for global food security.

GMO's cause food insecurity through the corporate control of the seed supply

Red flags ought to be flying concerning genetic engineering and the future of global food security. Food Insecurity is when control of food is in corporate rather than community hands. This is happening at an alarming rate. The number of patents on living organisms and their parts continues to grow. The international group ActionAid’s 2002 research revealed that six agrochemical companies hold over 900 patents on varieties of the world’s five major staple food crops. The year before, the U.S. Patent Office awarded 20,000 gene patents and another 25,000 were pending.

On a fundamental level, the traditional Jewish view of creation is that G-d is the ultimate owner of all life. However, Genetic engineering posits man as the creator of life. Human manipulation of genes and genetics through natural methods is historically widespread and is evidenced in the Torah by Jacob’s breeding of sheep in order to enlarge his own flock over that of Laban. However, current genetically modifying of organism is a totally different process. By taking genes from one species, be it plant, animal, or organism, and mixing it with a different organism, a novel species is created. This is going beyond the traditional role of man as co-creator with G-d, instead placing man as usurping G-d as original creator of life.

American and Israeli patent laws which grant patents on genes and living organisms goes against the most fundamental Jewish belief of G-d as creator. Jews as a whole and rabbinic authorities in particular ought to issue a statement condemning the patenting of life similar to that of the Council for Responsible Genetics, whose statement http://www.actionbioscience.org/genomic/crg.html concludes that, “Patents on life forms are ethically and morally unacceptable.

Learning from our ancestors

Let us learn from our ancestor Yaacov who successfully bred flocks of sheep using natural methods, and not repeat the sins of Noah's generation, who angered G-d through the mixing of species. Let us pay heed to the story of famine in Genesis 47, where the Egyptians first spend all their money in order to purchase food, then are forced to sell their livestock, and finally they are forced to sell their land to the Pharaoh, leaving the people as indentured servants. Instead, let us learn from the forethought of Joseph, who foresaw the coming time of food scarcity and took measures to prepare for it. The time of corporate controlled food supply due to the use of GMO's is at hand. Let us take steps to prevent this by moving away from genetically modified foods and toward community controlled, bio-diverse, and organic forms of agriculture. The future of our people and of the planet depends on it.

Conclusions and Next Steps

For all these religious, environmental and health reasons, the genetical modification of foods must be subject to increased religious scrutiny and study. Failure to do so could have devestating consequences to our health and to the vitality of the earth. Until this issue has been appropriately examined, we must err on the side of the precautionary principle and avoid exposure to genetically modified foods. In order to do this, rabbinic authorities and Jews worldwide need to demand manditory labelling of all genetically modified organisms.

It is incubent upon us Jews as caretakers of G-ds earth to examine the consequences of GMO’s and to advocate for the health of the planet, the land, and the species that depend on the earth, (including ourselves), by removing Genetically Modified Organisms from the food supply. We must be especially careful of the crops planted in the State of Israel, as our treatment of the land reflects our divine duty as caretakers of Eretz Yisroel. It has been shown that GMO’s make soil sterile and organisms that eat GMO's have much higher rates of infertility as well. This goes against G-d’s first commandment to mankind, to be fruitful and multiply. It seems that such a transgression cannot go ignored indefinitely, and that we as the Jewish people have both the responsibility and moral duty to address this issue and say "No! We refuse to eat foods that contain GMO’s!" Foods that cause such extreme health problems cannot be considered kosher or fit to eat. If such a call from the Jewish community were forthcoming, this could have the power to change the modern agro-petro-chemical-monoculture food system as we know it.

5 Replies to "Why Genetically Modified Foods Should Not Be Considered Kosher."

  • Deborah Klee Wenger
    December 1, 2010 (2:58 pm)

    Thank you for such a thorough analysis. This is really food for thought and spirit!

  • Evonne Marzouk
    December 10, 2010 (1:15 pm)

    Rafi – I’ve been thinking a lot about what you wrote. Here is my question. Do you keep kosher? And do you avoid all GMO products? I ask because every time someone says to me that GMOs should not be kosher, I wonder whether they really know what they are asking. Keeping kosher – for real – means not eating the stuff that isn’t kosher – at all. And GMOs are in so many things. That would put a LOT of food out of commission. Keeping kosher is already hard. It seems to me that many people who make these arguments on the basis of Jewish values have not fully thought through the implications. Do you yourself avoid all GMOs? Would you, if they were declared not kosher? Or is this just a values-based argument that wouldn’t have any teeth except for the small percent of Jews who keep kosher?

  • Leah K
    December 18, 2010 (6:26 pm)

    Thank you so much for this post. I couldn’t agree more. I avoid all GM foods and it always bugs me how frum circles seem to endorse the consumption of fake food — overly processed, genetically modified, etc. Since when was preserving a ‘kil yakar’ polluting oneself with this non-food crap?
    The issue you raise here goes much deeper, i.e. the role of the kashrut organizations and the rabbinic authorities in our health. if the FDA says that saccharin is safe for consumption (which they just did), does that mean it’s safe for us? The dangers of these issues lie in the rabbinic authorities being misinformed by the same profit-hungry big wigs that push drugs and disease onto our people and then deeming them not only not asur, but at times, even recommended (with other health/drug issues). This is when we run into big problems. Thank you for opening this discussion and I pray that the halachic authorities become enlightened about these real issues by more and more people like you and become truly informed about what Hashem really meant for us to put into our bodies.

    February 22, 2011 (11:59 pm)

    Thanks you all for the comments! Leah, I couldn’t agree with you more. Evonne, in answer to your question, I keep kosher to a large degree and am particularly careful to avoid consumption of treif animals. I wish I could say I also ate 100% Non-GMO, but unfortunately that’s a lot harder to do and with the absence of labeling and high likelyhood of gmo drift contamination, its virtually impossible for any of us. I see GMO’s as a part of what it means to truly keep Kosher. This is what bothers me so much, that I am not able to follow my religious convictions due to lack of honesty about where our ‘food’ is coming from.

  • Roger Price
    February 28, 2016 (9:50 pm)

    Since this post was published in 2010, Reform and Conservative rabbinic committees have considered whether genetically modified foods violate Jewish law. Neither group has found that such foods violate either kashrut or kilayim. Even more recently, the Obama White House and Pope Francis have issued approvals of one such food, Golden Rice. For more, please see http://www.judaismandscience.com/jews-judaism-and-genetically-modified-crops/

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