The human body derives from beta carotene sources, such as Golden Rice, only as much vitamin A as it needs. In the context of GMOs, Greenpeace claimed to stand for freedom.
In the Philippines, where Greenpeace was fighting to block field trials of Golden Rice, its hypocrisy was egregious. The government administered capsules to preschoolers twice a year, and to some pregnant women for 28 consecutive days.
If Greenpeace seriously believed that retinoids caused birth defects and should be a matter of personal choice, it would never have endorsed these programs. Despite this, the anti-GMO lobby went ballistic when scientists fed Golden Rice to 24 children during clinical trials in China.
The trials, conducted in , were designed to measure how much vitamin A the rice could generate in people who suffered from vitamin A deficiency. One group of kids was given Golden Rice, a second group was given beta carotene capsules, and a third was given spinach.
In a separate study, they found that an adult-sized serving could do the same for adults. Golden Rice was as good as capsules, and better than spinach, at delivering vitamin A. When Greenpeace found out about the trials, it enlisted the Chinese government to stop them. For all the scare talk about beta carotene, Schubert and his colleagues never mentioned the kids who were given beta carotene capsules in the studies. Nor did Greenpeace. Their sole concern was the rice.
Supporters of Golden Rice were baffled. Greenpeace was outraged. Should we allow ourselves to be subjects in a human experiment? Eventually, Tufts commissioned three reviews of the clinical trials. Two were internal; the third was external. So they ignored it. Their enmity is unappeasable; their alarmism is unfalsifiable. Take the question of allergies. In , scientists found no allergens among the proteins in Golden Rice.
The critics refused to accept this finding. They demanded additional tests. The critics openly advocate unattainable standards. And these standards apply only to GMOs. Three years ago Greenpeace recommended marker-assisted selection —essentially, breeding guided by genetic analysis—as a better way to increase levels of beta carotene and other nutrients. Shortly afterward, a study found that Greenpeace had it backward: In rice, marker-assisted selection caused more genetic and functional disruption than genetic engineering did.
They want studies to assess how much beta carotene the rice loses when stored at various temperatures. Two years ago anti-GMO activists destroyed a field trial of the rice in the Philippines. Last year they filed a petition to block all field tests and feeding studies. The stories of papaya, Bt, and Golden Rice demonstrate, in several ways, that these concerns are unfounded. Hundreds of studies have been done, and tons of GE food have been eaten.
No amount of evidence will convince the doomsayers that GMOs are safe. Let it go. In fact, if you look at illness or direct fatalities —or at correlations between food sales and disease trends , which anti-GMO activists like to do—you can make a better case against organic food than against GMOs.
Keeping you scared is the key to their political and business strategy. And companies like Chipotle, with their non-GMO marketing campaigns, are playing along. There are other criticisms, and one of them is worth your attention. Three-quarters of the corn and cotton grown in this country is engineered to resist insects. These crops have the bacterial Bt gene, which makes them lethal to bugs that eat them. Slightly more than that, about 80 percent to 85 percent of corn and cotton , is engineered to withstand weed-killing chemicals, especially glyphosate, which is sold as Roundup.
The two traits are usually packaged together. The percentages are similar for soy. Worldwide, insect-resistant crops are grown on about 50 percent of the land allotted to GMOs, while herbicide-tolerant crops are grown on more than 80 percent. Both applications are considered pesticidal, because weeds, like bugs, are pests.
And this is crucial to understanding the debate over whether GMOs, as a whole, have raised or lowered the level of pesticide use. An international analysis of multiple studies, published last year, calculates that GMOs decreased pesticide use by 37 percent. But the two assessments agree on a fundamental distinction: While bug-resistant GMOs have led to lower use of insecticides , herbicide-tolerant GMOs have led to higher use of weedkillers.
Two factors seem to account for the herbicide increase. One is direct: If your crops are engineered to withstand Roundup, you can spray it profusely without killing them. The other factor is indirect: When every farmer sprays Roundup, weeds adapt to a Roundup-saturated world.
They evolve to survive. To kill these herbicide-resistant strains, farmers spray more weedkillers. Benbrook has called it one of the safest herbicides on the market. But the arms race could change that. As weeds evolve to withstand Roundup, farmers are deploying other, more worrisome herbicides.
And companies are engineering crops to withstand these herbicides so that farmers can spray them freely. But this is misleading in two ways. First, by pooling the data, Chipotle has hidden half of what Benbrook found: that Bt crops reduced insecticide use and thereby, in terms of their contribution to the bottom line, reduced the combined use of pest-killing chemicals. To confound evolution, you have to make evolutionary pressures less predictable. That means switching herbicides so weeds that develop resistance to one herbicide will be killed by another.
It also means alternating crops, so weeds have to compete with different plants and grow under different tilling, watering, and harvest conditions. Industry and regulators, belatedly, are beginning to address this problem. As part of its product approval and renewal process, the EPA, backed by the USDA , is requiring producers of herbicides and herbicide-tolerant crops to monitor and report use of their chemicals, work with farmers to control excessive use, and promote non-herbicidal weed control methods.
GMOs are part of the problem. Herbicide-tolerant crops let farmers spray weedkillers more often and more thoroughly without harming their crops. Farmers have been cultivating homogeneity for millennia. Roundup has been used for more than 40 years. Chipotle illustrates the folly of renouncing GMOs in the name of herbicide control.
But shifting to sunflower oil is demonstrably counterproductive. They were bred to tolerate a class of herbicides called ALS inhibitors. And since farmers start[ed] relying on those herbicides, many weeds have evolved resistance to them.
In fact, many more weeds have become resistant to ALS inhibitors than to glyphosate. None of that is on the label. Herbicide-tolerant crops even mitigate climate change by reducing the need to till fields , which erodes soil and releases greenhouse gases.
The more you learn about herbicide resistance, the more you come to understand how complicated the truth about GMOs is. Then you realize that nothing is perfectly innocent. Pesticide vs. The best you can do is measure each practice against the alternatives. The least you can do is look past a three-letter label. Greenpeace and Chipotle think the logical response to this travesty is to purge GMOs. I have read numerous GMO risk assessment applications. Though these documents are quite long and quite complex, their length is misleading in that they primarily ask trivial questions.
Furthermore, the experiments described within them are often very inadequate and sloppily executed. Scientific controls are often missing, procedures and reagents are badly described, and the results are often ambiguous or uninterpretable. In consequence, the government regulators who examine the data are effectively reliant on the word of the applicants that the research supports whatever the applicant claims.
There are other elementary scientific flaws too; for example, applications routinely ignore or dismiss obvious red flags such as experiments yielding unexpected outcomes.
Aside from grave doubts about the quality and integrity of risk assessments, I also have specific science-based concerns over GMOs. These concerns are mostly particular to specific transgenes and traits. Many GMO plants are engineered to contain their own insecticides. These GMOs, which include maize, cotton and soybeans, are called Bt plants. Bt plants get their name because they incorporate a transgene that makes a protein-based toxin sometimes called the Cry toxin from the bacterium Bacillus thuringiensis.
Their makers believe each of these Bt toxins is insect-specific and safe. However, there are multiple reasons to doubt both safety and specificity. One concern is that Bacillus thuringiensis is all but indistinguishable from the well known anthrax bacterium Bacillus anthracis. Another reason is that Bt insecticides share structural similarities with ricin.
Ricin is a famously dangerous plant toxin, a tiny amount of which was used to assassinate the Bulgarian writer and defector Georgi Markov in [ 1 ]. A third reason for concern is that the mode of action of Bt proteins is not understood Vachon et al ; yet, it is axiomatic in science, that effective risk assessment requires a clear understanding of the mechanism of action of any GMO transgene so that appropriate experiments can be devised to affirm or refute safety.
All this is doubly troubling because some Cry proteins are toxic towards isolated human cells Mizuki et al. A second concern follows from GMOs being often resistant to herbicides. This resistance is an invitation to farmers to spray large quantities of herbicides, and many do. Glyphosate has been in the news recently because the World Health Organisation no longer considers it a relatively harmless chemical, but there are other herbicides applied to GMOs which are easily of equal concern.
Food manufacturers are not required to label if their food is genetically modified, but GMO labeling advocates continue to raise concerns surrounding this issue. Until laws change, there is some hope for steering clear of GMOs if you wish to do so. The following guidelines may help you keep the GMOs in your diet to a minimum:.
Buy food that is labeled percent organic. It has no GMOs. Choose whole foods that you can prepare yourself instead of processed or prepackaged foods. Purchase grass-fed beef. Shop at local farmers markets.
These are much less likely to carry genetically-altered foods. But that study would have to be so complex to get to the bottom of it. There would have to be various study groups to include those eating processed foods and those eating a healthy diet. Get more Living Better nutrition tips. There is another allergy risk associated with GE foods. These foods could be creating thousands of different and new allergic responses. Each of these numerous novel proteins could create an allergic response in some consumers.
The FDA was also well aware of this new and potentially massive allergenicity problem. However, the FDA again ignored its own scientists. Because these foods were allowed to be marketed without mandatory testing for this kind of allergenicity, millions of unsuspecting consumers have continuously been exposed to a potentially serious health risk.
This FDA action is especially negligent in that the potential consequences of food allergies can include sudden death, and the most significantly affected population is children. Another hidden risk of GE foods is that they could make disease-causing bacteria resistant to current antibiotics, resulting in a significant increase in the spread of infections and diseases in the human population. For example, a genetically engineered maize plant from Novartis includes an ampicillin-resistance gene.
Ampicillin is a valuable antibiotic used to treat a variety of infections in people and animals. A number of European countries, including Britain, refused to permit the Novartis Bt corn to be grown, due to health concerns that the ampicillin resistance gene could move from the corn into bacteria in the food chain, making ampicillin far less effective in fighting a wide range of bacterial infections.
The well-respected British medical journal, The Lancet , published an important study conducted by Drs. Arpad Pusztai and Stanley W. Ewen under a grant from the Scottish government. The study examined the effect on rats of the consumption of potatoes genetically engineered to contain the biopesticide Bacillus Thuringiensis B. Thescientists found that the rats consuming geneticallyaltered potatoes showed significant detrimentaleffects on organ development, body metabolism, and immune function.
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