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with Joe Pizzorno, Jr., ND

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Tuesday, November 20, 2007

Genetically Modified Foods: Just Say No!

Just Say “No” to GMO
This is perhaps the most controversial article we have written so are far for this blog. While we only cite one data source, Smith’s Genetic Roulette, we spot checked several research articles and did a PubMed search that appears to confirm the seriousness of this issue.

Are GMO foods the next best hope for feeding our planet or should we follow the example set by consumers in the European Union, whose outcry reached such proportions that, in April 1999, virtually all major manufacturers publicly committed to stop using GM ingredients in their European brands?

The Case for GMOs

According to the GMO industry, there are many good reasons to use GMOs:

  • Reduced need for herbicides
  • Reduced need of pesticides
  • Reduced greenhouse emissions as GMOs require less tillage or plowing, thus less use of fossil fuels
  • Ability to manipulate foods to increase desirable components such as nutrients
  • Increased production of food for starving third world countries.

These are certainly worthwhile goals, and humans have been successfully modifying the genetics of their food supply for centuries.

The supporters assert that over a trillion GMO meals have been eaten, thus proving their safety. The problem, of course, is that the new technology is far different from the hybridization and selection methods used in the past.

The big question: “Are GMOs safe?”

The EU Consumer-Led Revolt
The EU consumer-led revolt against GMOs was triggered in February 1999 when media coverage exploded after top GMO safety researcher, Dr. Arpad Pusztai was called to speak before Parliament and went public with some very alarming research results.

Dr. Pusztai, a highly respected leader in the field with 35 years employment at the Rowett Institute in Scotland, had been given a UK government grant to design the long-term testing protocols that were supposed to be part of the European GM food safety assessment process. When Pusztai fed rats GM potatoes genetically engineered to produce a supposedly safe insecticide called the GNA lectin, all the animals showed potentially pre-cancerous cell growths, smaller brains, livers and testicles, partially atrophied livers, and damaged to the immune system–with most changes appearing after just 10 days.

Since other rats fed normal potatoes spiked with GNA lectin–even 700 times more GNA lectin than was present in the GM potatoes–did not develop these problems, Pusztai’s results indicated that the problem lay with genetic engineering process itself. And that meant that all GM foods created from the same process, including those already on the market, might produce unintended ill effects.

According to Pusztai, when he expressed his concerns, he was fired and threatened with a lawsuit if he discussed his research. His 20-member research team was disbanded; the testing protocols were dropped, and a campaign was begun by pro-GM forces to discredit the study. Then an invitation to testify before Parliament allowed Pusztai to tell his story, and all hell broke loose. By April 1999, the protests of informed consumers had convinced manufacturers that GMOs would not sell in the EU, and all agreed to keep GMOs out of their European products, in spite of official approvals by a pro-GM European Commission.

Americans Ill-Informed about GMOs
In the U.S., the Pusztai story got virtually no press, and the U.S. mainstream media has failed to discuss other data suggesting GM foods may pose enormous health risks, including:

  • A preliminary study from the Russian National Academy of Sciences finding that more than half the offspring of mother rats fed GM soy died within three weeks (compared to 9% from mothers fed natural soy).
  • The estimated 10,000 sheep that died in India within 5-7 days of grazing on GM cotton plants engineered to produce their own Bt-toxin pesticide.
  • The only human GM feeding study ever published, which shows that the foreign genes inserted into GM food crops can transfer into the DNA of our gut bacteria. This study gives new meaning to the adage, “You are what you eat.” Long after those GM corn chips you munched are history, your intestinal flora may still be churning out the “Bt” pesticide GM corn plants have been engineered to produce.

U.S. consumers mistakenly believe that, unless the FDA had approved each and every GM food through rigorous, well designed, long-term studies, GM food ingredients would not be allowed in our food supply and certainly could not be omnipresent in prepared foods in the form of corn, soy, cottonseed and canola derivatives.

Reality is that the FDA has absolutely no GMO safety testing requirements, and GM ingredients are ubiquitous in prepared foods. Unless a processed food contains only organic ingredients, it is highly likely to contain GM ingredients. The “research” that supports GMO safety is voluntarily provided by companies on their own GM crops and has been described by critics as “meticulously designed to avoid finding problems”.

But 44,000 FDA internal documents later made public as a result of a lawsuit revealed problems. The overwhelming consensus among the FDA’s scientists was that GM foods were substantively different, so different that their consumption might result in unpredictable and hard-to-detect allergens, toxins, new diseases and nutritional problems. Agency scientists urged superiors to require long-term studies, but were not only ignored, their statements about possible negative effects of GMOs were progressively deleted from FDA policy statement drafts. Evidence of this FDA activity was presented at a Washington, D.C., press conference in 1999, another story major media didn’t publicize.

The result: The same companies that carefully avoid including GM ingredients in their European products are feeding GMOs to ill-informed consumers in the U.S. Americans know so little about GMOs that, although virtually all of us have now, albeit unwittingly, consumed GM foods (the vast majority of processed foods contain derivatives from the four major GM crops: soy, corn, cottonseed and canola), only about 1 in 4 realize it.

What’s the Problem with GMOs?
The way they are created disrupts the plant’s DNA in unintended, potentially harmful ways.

In genetic engineering, a single gene is removed from one organism and forcibly inserted into another. First, scientists identify the gene they want and analyze its sequence. (If the source gene is to be taken from bacteria, some of its sequence has to be rearranged
because bacteria produce certain amino acids using a code different from the one used by plants).

After figuring out a working gene sequence, engineers add a promoter sequence at one end of the gene to turn it on (the most popular one in GM crops being CaMV 35S, which forces the gene to constantly churn out the protein), and a terminator sequence at the other end (which tells the DNA to stop). Lastly, scientists add a marker gene, usually one that confers antibiotic resistance, so they can later douse the plant cells with antibiotics, killing off normal cells and revealing those that have been genetically modified. This combination of gene sequences – called a “gene cassette” – is then multiplied into millions and inserted into target plant cells via one of two primary methods, both of which trigger a wound response the cell.

One method employs a bacterium (Agrobacterium tumefaciens), which normally infects a plant by inserting a portion of its own DNA into the plant’s DNA and then causing the plant to produce tumors. Genetic engineers remove the tumor-creating section of this bacterium’s DNA and replace it with the desired gene cassette, so the bacterium “infects” the plants with the foreign genes instead.

The second method uses a gene gun. Scientists coat millions of particles of tungsten or gold with gene cassettes and blast them into millions of plant cells, only a few of which incorporate the foreign gene cassette.

In either of the two delivery forms, the next step is the application of the antibiotic to which the gene cassette confers resistance. Most of the plant cells die, but a few – the ones in which the transgene has inserted – survive. These are developed into plants that researchers can duplicate by making clones through tissue culture or harvesting the seeds.

Each plant grown from a gene insertion is unique because where the transgene ends up integrating itself into the host DNA is uncontrolled and cannot be reproduced. For this reason, the possible consequences to the plant’s DNA are different with each insertion, so all plants developed from a specific insertion are collectively referred to as an “event.”

In sum, genetic engineering artificially combines genes from different species and forcibly inserts them into unknown and random locations on the host genome. The procedure, which disrupts the precise orchestration of thousands of genes that has evolved over millennia in the normal plant’s genome, is highly mutagenic. (We now know that genes, like nutrients, do not work singly, but as part of highly integrated networks.) Plus it introduces bacterial genes for drug resistance along with strong promoters to express the foreign proteins at high levels in all parts of the plant.

In his book, Genetic Roulette, Jeffrey M. Smith, provides a detailed discussion of the documented health risks of GMOs, including evidence of reactions seen in animals and humans. Following are just a few of the indications he provides that GMOs are significantly changed by the process and may produce undesirable effects:

  • Evaluation of gene insertion sites have shown relocations of up to 40,000 DNA base pairs, mixing together of foreign and host DNA, large scale deletions of more than a dozen genes and multiple random insertions of foreign DNA fragments.
  • During insertion, the foreign gene may become truncated, rearranged or interspersed with extraneous pieces of DNA. The proteins produced by the distorted foreign gene may be misfolded or have added molecules, so they may operate differently and be harmful in unpredictable ways.
  • One study using a micro-array gene chip found that 5% of the host’s genes changed their levels of expression after a single gene was inserted.
  • The promoter used in nearly all GM crops permanently turns on the foreign gene at high output. Scientists had thought the promoter would only turn on the foreign gene, but, in fact, it can accidentally turn on other natural plant genes–permanently–genes that may overproduce an allergen, toxin, carcinogen or anti-nutrient, or regulators that block other genes.
  • When certain viruses infect an organism, they splice themselves into the host’s DNA. If the GM promoter is inserted in the vicinity of a dormant virus, it might switch it on, resulting in virus activation.
  • In GMO Roundup Ready soybeans, the “stop signal” placed at the end of the gene cassette is dysfunctional, so longer than intended RNA proteins are produced, which are further rearranged into four non-intended variants, any one of which might be harmful.
  • DNA changes in GM plants can alter the amounts of the chemicals the plant naturally produces, increasing its output of toxins or decreasing the amount of protective phytonutrients produced. For example, GM soybeans produce less cancer-fighting isoflavones.
  • GM proteins in soybeans, corn and papaya are similar to known allergens and may cause allergies.
  • Transgenes survive digestion and can transfer to gut bacteria or move into the blood and organs, including passing through the placenta into the fetus and through the blood-brain barrier. The only human feeding trial ever published confirmed that genetic material from Roundup Ready soybeans transferred into the gut bacteria in three of seven human volunteers. Once in the human gut bacteria, the transferred portion of the transgene produced herbicide-resistant protein. If the antibiotic-resistant genes that have been inserted into most GM foods on the market were to transfer to pathogenic bacteria in the gut, antibiotic-resistant diseases could develop. If the transgene for the Bt pesticide were to transfer to our gut bacteria, we could become living pesticide factories.

Sound scary? The limited amount of research and case reports regarding what actually happens when animals and people consume GM foods is not reassuring. Here are just a few highlights from Smith’s coverage of GMO’s effects:

  • Rats fed Monsanto’s Mon 863 Bt corn for 90 days showed significant changes in their blood cells, livers and kidneys.
  • Rats were fed the GM FlavrSavr tomato for 28 days. Seven of 20 rats developed stomach lesions (bleeding stomachs); another 7 of 40 died within two weeks.
  • About 25% of the sheep in herds grazing continuously on Bt cotton plants in India after the cotton harvest died within a week, according to reports from 4 villages. Post mortem studies suggested a toxic reaction.
  • Twelve dairy cows died on a farm in Hesse Germany, after being fed a diet with significant amounts of the GM corn variety, Bt 176. Other cows in the herd developed a mysterious illness and had to be killed. Syngenta, the producers of Bt 176, compensated the farmer for part of his losses, but despite the farmer’s demands and public protests, no detailed autopsy reports were made available.
  • More than 20 farmers in North America have reported that pigs fed GM corn had low conception rates, false pregnancies or gave birth to bags of water. Both male and female pigs became sterile.
  • In mice fed GM soy, production of alpha-amylase, an enzyme responsible for digesting starch, dropped by as much as 77%.
  • In male mice fed Roundup Ready soybeans, the structure and gene expression pattern of testicular cells changed significantly.
  • Female rats were fed Roundup Ready soy starting before conception and continuing through weaning. 55.6% of the offspring died within three weeks compared to 9% of non-GM soy controls. In another study, after a lab began feeding rats a commercial diet containing GM soy, offspring mortality reached 55.3%. When offspring from the GM-fed r
    ats were mated together, they were unable to conceive.
  • In 2003, approximately 100 people living next to a Bt cornfield in the Philippines developed skin, respiratory, intestinal reactions and other symptoms while the corn was shedding pollen. Blood tests of 39 people showed an antibody response to Bt-toxin. Symptoms reappeared in 2004 in at least four other villages that planted the same GM corn variety.
  • GM soy was imported into the UK shortly before 1999. Within a year, soy allergies in the UK had risen from 10% to 15% of the sampled population. Antibody tests show that some individuals react differently to GM and normal soy varieties. GM soy has higher levels of a known allergen.
  • One brand of the supplement L-tryptophan created a deadly epidemic in the U.S. in the 1980s. The company responsible had genetically engineered bacteria to produce the supplement more economically. The resulting product contained many contaminants, five or six of which were suspected as the cause of the disease. Not only the GM L-tryptophan supplement, but all L-tryptophan was removed, and still remains off the market.

Bottom Line
A PubMed search on “GMO” and “Safety” yielded 41 articles. Restricting the search to human studies dropped that to 20 articles. Restricting further to clinical trials yielded only one study, and it was of ability to track the presence of GMOs in the food supply!

Here is a list of the titles of the first 20 articles returned by this PubMed search:

  • Reappraisal of biosafety risks posed by PERVs in xenotransplantation.
  • Session VII: Risk management and monitoring.
  • The politics and science behind GMO acceptance.
  • Model for tuning GMO detection in seed and grain.
  • Approaches in the risk assessment of genetically modified foods by the Hellenic Food Safety Authority.
  • Biological safety concepts of genetically modified live bacterial vaccines.
  • Molecular farming on the rise–GMO regulators still walking a tightrope.
  • New measures of insecticidal efficacy and safety obtained with the 39K promoter of a recombinant baculovirus.
  • Need for an “integrated safety assessment” of GMOs, linking food safety and environmental considerations.
  • European GMO labeling thresholds impractical and unscientific.
  • [Application of near-infrared diffuse reflectance spectroscopy to the detection and identification of transgenic corn]
  • Role of the “National Reference Centre for Genetically Modified Organisms (GMO) detection” in the official control of food and feed.
  • GMO: human health risk assessment.
  • Regulations governing veterinary medicinal products containing genetically modified organisms in the European community.
  • Assessment of novel foods in animal nutrition.
  • The human side of GMO biosafety research.
  • GMO biosafety research in China.
  • Allergy assessment of foods or ingredients derived from biotechnology, gene-modified organisms, or novel foods.
  • Public health issues related with the consumption of food obtained from genetically modified organisms.[Genetically modified plants and food safety. State of the art and discussion in the European Union]

The rest of the article titles were similar. Notice something missing? No actual human research published! These are all opinion articles and recommendations on how to determine safety. But virtually no actual research. Now, we realize that such studies may have been published in food technology journals that are not in Medline. However, the medical research world is where we live and where we trust the results of the peer-review process.

The answer to our question, “Are GMOs safe?” is very clear: we don’t know.

The surprising lack of studies published in the scientific medical literature is, to us, a huge red flag. If these are so safe, where are the actual human studies? The assertion that a trillion meals have been eaten is not compelling. If there is no actual system in place for monitoring the impacts of these foods and virtually everyone in the US is eating them every day then how is their safety to be assessed?

How to Go Non-GMO
If the risks documented in Genetic Roulette raise enough questions about GMOs’ potential for harm that you wish to avoid consuming GMOs until more research has been done – research not controlled by the biotech companies – here are a few tips.

If you are traveling to Europe, no worries. GMOs are banned in EU foods. In the United States and Canada, however, GM foods are not only legal, but are unlabeled, so avoiding them can be challenging.

Eat Organic:
Organic foods are not allowed to contain GM ingredients. Even the small percentage of non-organic ingredients allowed in foods labeled organic is not allowed to contain GMOs.

Prepared or Processed Foods:

  • Most generic vegetable oils and margarines used in restaurants and in processed foods in North America are made from soy, corn, canola, or cottonseed—the four major genetically engineered crops. Avoid these oils, unless they are organic or labeled non-GMO. Choose any other oil, e.g., olive, sunflower, or safflower.
  • Check the list of ingredients for GM enzymes, additives, sweeteners, soy and/or corn derivatives. Genetically modified bacteria and fungi are used in the production of enzymes, vitamins, food additives, flavorings and processing agents in thousands of foods on the grocery shelves as well as health supplements.
  • Flavorings such as vanillin and hydrolyzed vegetable protein, which is derived from corn and soy, can also come from GM sources. Xanthan gum is another product that may be derived from a GM process.
  • Aspartame, the diet sweetener, is a product of genetic engineering.
  • Honey can be produced from GM crops. For example, some Canadian honey comes from bees collecting nectar from canola. This has shut down exports of Canadian honey to Europe.
  • Most packaged foods contain soy and/or corn derivatives, e.g., soy or corn oil, soy flour, soy protein, soy lecithin, textured vegetable protein, corn meal, corn syrup, dextrose, maltodextrin, fructose, citric acid, lactic acid. Non-GMO alternatives can be found not only in health food stores, but in supermarkets. Mayonnaise, for example, which is traditionally made with soy oil, can be found in both non-GM soy and safflower varieties.

Vitamin Supplements: Among vitamins, vitamin C (ascorbic acid) is often made from corn; vitamin E is usually made from soy. Vitamins A, B2, B6, and B12 may be derived from GMOs as well. In addition, vitamin D and vitamin K may have “carriers” derived from GM corn sources, such as starch, glucose, and maltodextrin. In addition to finding these vitamins in supplements, they are sometimes used to fortify foods. Organic foods, even if fortified with vitamins, are not allowed to use ingredients derived from GMOs.

Eating Out:

  • Ask what oil is used for cooking. If the answer is “vegetable oil,” margarine, soy, cottonseed, canola or corn oils, ask if olive or some other oil can be used instead or for something cooked without oil. Check to ma
    ke sure the olive oil is pure and not a blend of canola and olive.
  • Avoid menu items with dairy, unless organic, and items made with non-organic meat. Very few restaurants buy organic milk or milk certified to be from cows that are not treated with genetically modified rbGH, and both non-organic meat and dairy products usually come from animals that have eaten GM feed. Also, a common enzyme, chymosin (called rennet), used in the production of hard cheeses, was formerly derived from the stomach linings of calves. In 1990, a GM cbymosin was introduced and is now found in more than 70% of non-organic U.S. cheeses.
  • Ask what foods are freshly prepared. Avoid menu items made with packaged sauces or processed foods since most contain GM derivatives (e.g., corn and soy derivatives).
  • Avoid desserts made with aspartame.

For an extensive list of foods by brand and category, indicating if they have GM ingredients, see

Smith, JM. Genetic Roulette, Yes! Books, Fairfield, Iowa, 2007.

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Posted by: Joe Pizzorno, Jr., ND at 1:51 pm