Do GMO foods cause any health related risks?

foodI don’t believe they do but I keep hearing this from many of my friends and I would like to shut them up once and for all. If you have any studies or papers you could refer me to I would be ever so grateful.

Everything we do in life has some degree of risk associated with it. What we have to consider is whether the benefits provided outweigh the risks. I believe that in the case of genetically modified organisms, they do. The literature on this subject is vast. You ask me to provide references to silence your friends. I could provide reems. But the anti-GMO activists could also provide a selection of papers that support their arguments. It comes down to the weight of evidence, which I think is quite firmly on the “pro” side, but it takes a lot of reading and a solid understanding of the science involved to come to that conclusion. We have been consuming food with some components derived from genetically modified plants for decades with no hint of a health hazard in humans but I am not going to suggest that there aren’t some contentious issues about genetic modification.  Of course there are, just like with any new technology.  And I’m certainly not going to say that scientists can absolutely guarantee that genetic modification of foods will have no pitfalls.  Nobody can make such a guarantee.  Indeed, demanding unqualified assurance about the safety of genetically modified foods is just plain naive.  We don’t make such demands in other aspects of life.  We don’t say that we will not fly in an airplane unless we are assured that it will not crash because we realize that this would be an absurd request.  We fly because in our mind we know that the benefits outweigh the risks.  This is also how we have to look at genetically modified foods.

First of all, let’s understand that just because something may be good for Monsanto, Novartis, AstraZeneca or any other company involved in biotechnology, it isn’t necessarily bad for the public.  But if you listen to some alarmists, you can get the impression that these companies are trying to foist poisons on us purely for the sake of profit.  Of course, there is a buck to be made.  But profits come with the production of good and useful products.  No company wants to undermine its existence by marketing dangerous substances.  A great deal of of research has gone into genetic modification and its safety aspects.  Many of the potential problems that are now being vocalized by opponents were in fact addressed long ago by the industry.  The testing for allergens in modified foods has been going on since the inception of the technology.  In one case, the addition of a Brazil nut gene to soybeans in order to increase the quality of the protein for improved animal feed resulted in the transfer of an allergen.  In other words, someone with a Brazil nut allergy could have reacted to eating the genetically modified soybeans.  But the problem was picked up in routine testing and the soybeans, which had been intended to be used for animal feed only anyway, were never marketed.

We should also note that this presents quite a different scenario from non-genetically modified food.  We don’t ban peanuts, or strawberries or fish because some people have allergies to these foods.  And these allergies are far more prevalent than the theoretical allergies to modified foods.  Indeed, it may be possible to genetically modify peanuts to eliminate the protein that is responsible for allergies.

Opponents of genetic modification suggest that we should be satisfied with the normal process of cross-breeding plants to produce improved varieties.  But where is the guarantee that this procedure doesn’t introduce undesired chemicals?  Appropriate cross-breeding can, for example, yield plants that are more resistant to insects.  And why don’t insects attack them?  Because these plants contain more natural toxins than other plants.  Nobody knows the human consequences of eating these natural pesticides.  Why are the activists not demanding that all hybrid plants, or indeed, that all plant foods be tested for natural toxins?

Let me allow for the possibility that genetically altered foods may present some yet unidentified risk.  One can always conjur up some theoretical catastrophe.  But let’s, however, compare this to the very real benefits that genetic modification can offer.  Combatting malnutrition, for one.  When people think of malnutrition, they usually think of starving children.  But that is not the only kind of malnutrition out there.  In fact the most common kind of malnutrition in the world is iron deficiency.  This can cause intellectual impairment, suppressed immunity and complications in pregnancy.  There are millions of people in the world who suffer from iron deficiency anemia!  Most of them subsist on rice as their dietary staple, a grain that contains very little iron, and the iron it does contain is unabsorbable because of the presence of substances called phytates.  These compounds bind iron in the digestive tract and substantially prevent it from being transported across the intestinal wall into the bloodstream.

Genetic modification has resulted in a variety of rice that has more iron.  This was accomplished by inserting a gene isolated from the French bean into the DNA of the rice.  This particular gene codes for the synthesis of a protein called ferritin, which is an iron storage protein.  In other words, the rice now can incorporate more iron from the soil.  Furthermore, another gene, this time from a fungus, which codes for an enzyme that breaks down phytates was also incorporatedcthereby making iron more available.

Populations that subsist on rice also suffer from vitamin A deficiency.  That’s because rice is very low in beta-carotene, the body’s precursor for vitamin A.  Deficiency of this vitamin is a major cause of blindness in the developing world; it is estimated that some 250 million children have vitamin A levels low enough to cause impaired vision.  Lack of vitamin A also predisposes to various cancers and skin problems.

This problem was addressed by introducing into rice four genes which code for proteins that enhance beta-carotene synthesis, two from daffodils and two from a bacterium.  The rice is yellow, clearly demonstrating that it is now fortified with beta-carotene.  Experiments are under way to cross the iron-rich rice with the beta-carotene-rich rice to produce a variety of super rice that can alleviate nutritional problems that affect billions of people!

There are many other fascinating possibilities.  How about genetically modifying foods to contain higher levels of cancer-fighting compounds such as sulphoraphane found in broccoli?  Or fresh fruits and vegetables with improved shelf lives?  Edible vaccines?  Crops that will flourish is salty soil?  All realistic possibilities.

But I can hear the critics’ minds churning away.  Why am I not talking about Monarch butterflies being killed by corn that has been engineered to contain a gene from the Bacillus thuringiensis (Bt) bacterium to protect it against the European corn borer?  Or the possibility of weeds developing resistance through cross pollination from crops that have been genetically engineered to be herbicide resistant?  Or a study that claimed rats fed genetically modified potatoes developed gastric problems?  Simply because in my judgement, based on the available scientific literature, these concerns have been addressed and either found to be unrealistic or solvable.  Surrounding a corn field with a few rows of non-Bt corn, for example, minimizes the Monarch butterfly problem.

Genetic modification is a hugely complex scientific, economic, political and emotional issue.  This certainly is not my last say on the subject.  Maybe I’ll even have to eat crow some time.  But by then we’ll probably have a genetically modified version that is nutrient filled and highly palatable.I don’t believe they do but I keep hearing this from many of my friends and I would like to shut them up once and for all. If you have any studies or papers you could refer me to I would be ever so grateful.

Everything we do in life has some degree of risk associated with it. What we have to consider is whether the benefits provided outweigh the risks. I believe that in the case of genetically modified organisms, they do. The literature on this subject is vast. You ask me to provide references to silence your friends. I could provide reems. But the anti-GMO activists could also provide a selection of papers that support their arguments. It comes down to the weight of evidence, which I think is quite firmly on the “pro” side, but it takes a lot of reading and a solid understanding of the science involved to come to that conclusion. We have been consuming food with some components derived from genetically modified plants for decades with no hint of a health hazard in humans but I am not going to suggest that there aren’t some contentious issues about genetic modification.  Of course there are, just like with any new technology.  And I’m certainly not going to say that scientists can absolutely guarantee that genetic modification of foods will have no pitfalls.  Nobody can make such a guarantee.  Indeed, demanding unqualified assurance about the safety of genetically modified foods is just plain naive.  We don’t make such demands in other aspects of life.  We don’t say that we will not fly in an airplane unless we are assured that it will not crash because we realize that this would be an absurd request.  We fly because in our mind we know that the benefits outweigh the risks.  This is also how we have to look at genetically modified foods.

First of all, let’s understand that just because something may be good for Monsanto, Novartis, AstraZeneca or any other company involved in biotechnology, it isn’t necessarily bad for the public.  But if you listen to some alarmists, you can get the impression that these companies are trying to foist poisons on us purely for the sake of profit.  Of course, there is a buck to be made.  But profits come with the production of good and useful products.  No company wants to undermine its existence by marketing dangerous substances.  A great deal of of research has gone into genetic modification and its safety aspects.  Many of the potential problems that are now being vocalized by opponents were in fact addressed long ago by the industry.  The testing for allergens in modified foods has been going on since the inception of the technology.  In one case, the addition of a Brazil nut gene to soybeans in order to increase the quality of the protein for improved animal feed resulted in the transfer of an allergen.  In other words, someone with a Brazil nut allergy could have reacted to eating the genetically modified soybeans.  But the problem was picked up in routine testing and the soybeans, which had been intended to be used for animal feed only anyway, were never marketed.

We should also note that this presents quite a different scenario from non-genetically modified food.  We don’t ban peanuts, or strawberries or fish because some people have allergies to these foods.  And these allergies are far more prevalent than the theoretical allergies to modified foods.  Indeed, it may be possible to genetically modify peanuts to eliminate the protein that is responsible for allergies.

Opponents of genetic modification suggest that we should be satisfied with the normal process of cross-breeding plants to produce improved varieties.  But where is the guarantee that this procedure doesn’t introduce undesired chemicals?  Appropriate cross-breeding can, for example, yield plants that are more resistant to insects.  And why don’t insects attack them?  Because these plants contain more natural toxins than other plants.  Nobody knows the human consequences of eating these natural pesticides.  Why are the activists not demanding that all hybrid plants, or indeed, that all plant foods be tested for natural toxins?

Let me allow for the possibility that genetically altered foods may present some yet unidentified risk.  One can always conjur up some theoretical catastrophe.  But let’s, however, compare this to the very real benefits that genetic modification can offer.  Combatting malnutrition, for one.  When people think of malnutrition, they usually think of starving children.  But that is not the only kind of malnutrition out there.  In fact the most common kind of malnutrition in the world is iron deficiency.  This can cause intellectual impairment, suppressed immunity and complications in pregnancy.  There are millions of people in the world who suffer from iron deficiency anemia!  Most of them subsist on rice as their dietary staple, a grain that contains very little iron, and the iron it does contain is unabsorbable because of the presence of substances called phytates.  These compounds bind iron in the digestive tract and substantially prevent it from being transported across the intestinal wall into the bloodstream.

Genetic modification has resulted in a variety of rice that has more iron.  This was accomplished by inserting a gene isolated from the French bean into the DNA of the rice.  This particular gene codes for the synthesis of a protein called ferritin, which is an iron storage protein.  In other words, the rice now can incorporate more iron from the soil.  Furthermore, another gene, this time from a fungus, which codes for an enzyme that breaks down phytates was also incorporatedcthereby making iron more available.

Populations that subsist on rice also suffer from vitamin A deficiency.  That’s because rice is very low in beta-carotene, the body’s precursor for vitamin A.  Deficiency of this vitamin is a major cause of blindness in the developing world; it is estimated that some 250 million children have vitamin A levels low enough to cause impaired vision.  Lack of vitamin A also predisposes to various cancers and skin problems.

This problem was addressed by introducing into rice four genes which code for proteins that enhance beta-carotene synthesis, two from daffodils and two from a bacterium.  The rice is yellow, clearly demonstrating that it is now fortified with beta-carotene.  Experiments are under way to cross the iron-rich rice with the beta-carotene-rich rice to produce a variety of super rice that can alleviate nutritional problems that affect billions of people!

There are many other fascinating possibilities.  How about genetically modifying foods to contain higher levels of cancer-fighting compounds such as sulphoraphane found in broccoli?  Or fresh fruits and vegetables with improved shelf lives?  Edible vaccines?  Crops that will flourish is salty soil?  All realistic possibilities.

But I can hear the critics’ minds churning away.  Why am I not talking about Monarch butterflies being killed by corn that has been engineered to contain a gene from the Bacillus thuringiensis (Bt) bacterium to protect it against the European corn borer?  Or the possibility of weeds developing resistance through cross pollination from crops that have been genetically engineered to be herbicide resistant?  Or a study that claimed rats fed genetically modified potatoes developed gastric problems?  Simply because in my judgement, based on the available scientific literature, these concerns have been addressed and either found to be unrealistic or solvable.  Surrounding a corn field with a few rows of non-Bt corn, for example, minimizes the Monarch butterfly problem.

Genetic modification is a hugely complex scientific, economic, political and emotional issue.  This certainly is not my last say on the subject.  Maybe I’ll even have to eat crow some time.  But by then we’ll probably have a genetically modified version that is nutrient filled and highly palatable.

Joe Schwarcz

2 Responses to “Do GMO foods cause any health related risks?”

  1. Penni Wisner says:

    Good grief. This post denies health concerns from GMO foods yet the background reading for the course, Food For Thought, includes a research paper reviewing research that comes to a different, more modulated and thoughtful conclusion. ????? This is why I have ambivalent feelings about many blog posts which are essentially opinion pieces, not research and/or peer reviewed.

  2. yaelb says:

    I feel like this article mixes the (1) science/engineering side of process, knowledge, development and technology with (2) the commercial side of profit and market share, (3) the governmental side of regulation, safety, checks and balances, and representations of voters desires, and (4) the side of biological sciences that are concerned with multi-generational time frames and culture.
    As a reader, I would have found it more helpful if this blog had started with the first sentence of the last paragraph and then separated the arguments pro and con explicitly into their different scientific, economic, and political domains. The reason I would find clear distinctions less disturbing is because I think each domain has its own rational and independent conclusion, which is what I think is helpful to see. My emotional issue evolves when scientific achievement is exploited for purely commercial gain without political regulation concerned for long-term consequences to its citizens and the common disregard for citizens rights demonstrated historicaly by commercial interests (slavery being an obvious one).
    Someone once explained power to me as coming from one of three sources: Knowledge, Strength, and Money. If we have a triumvirate of government (which includes a military arm), higher education, and for-profit companies, we then have a means of estimating the relative power of each. I think the GMO history and implementation, with its patents and distasteful disrespect for reasonable caution in introducing new products into the wild without sufficiently rigorous testing of hypotheses on what the consequences actually will be, is one example of how ownership of knowledge can be used to strengthen companies and weaken universities.

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