GMOs and Glyphosate

I have set before thee life and death, blessing and cursing: therefore choose life. (Deuteronomy 30:19)

Most people have heard the word GMO, but few can tell you what it means. Fewer still have heard the word glyphosate, even though most of them ate some of it today, probably before lunch.

In this chapter I want to slow down and explain both. I want to teach you what genetic engineering actually does to a crop, how much of our food supply it touches, why the weed killer sprayed on the crop may matter more to our health than the gene inserted into it, what the research and the courts have said, and how a family, even a family on a tight budget, can shop around both.

The verse at the head of this chapter is the framework. Every time we stand in a grocery aisle, we are choosing. Most of us were never told there was a choice to make; the packaging certainly was not going to mention it. By the end of this chapter, you will know.

The Aggregator and the Modern American Diet

Much of what I teach in this chapter and the next comes to us through one man, so I want to introduce him briefly.

Dr. Joseph Mercola is an osteopathic physician who began his career as a conventional family doctor in suburban Chicago, doing what most physicians of his generation did: handing out medications and chasing symptoms. What changed him was what he saw over years of practice. The patients he was caring for with the standard protocols were not getting better. The chronic conditions (diabetes, heart disease, autoimmune disease, depression, fatigue) kept worsening even as the medications multiplied. More pills, same patients, no better. So he began to read the nutrition literature and to address chronic illness through food, and he began to see results he had been told were not possible.

In 1997, in the early days of the consumer internet, back when going online still came with a screech from the modem, he started a website, Mercola.com. Within a decade it was one of the most widely read natural health websites in the world. What Dr. Mercola became, through that work, was an aggregator. He read everything. He interviewed nearly every significant voice in the field, Dr. Blaylock among them, and he translated their work into language ordinary people could understand and act on. He did not invent most of what he taught. He gathered it, put it in one place, and made it findable, a librarian with a very large reading list. His special reports, like The Ultimate Guide to GMOs that I quote all through this chapter, gather hundreds of studies into practical guides.

What Dr. Mercola has argued about our food, across thousands of articles and many books, comes down to a few simple propositions.

The first. The modern American diet, as it has developed since about 1950, is the most thoroughly processed and chemically modified diet any human population has ever eaten at scale. Ultra-processed food, made industrially from refined ingredients and combined with additives, now supplies more than sixty percent of the calories of the average American adult, and even more for children. More than half our dinner, in other words, was designed in a factory before it ever saw a plate.

The second. That shift has brought three chemical changes that are especially destructive to health: high-fructose corn syrup as the dominant sweetener (Chapter 8), industrial seed oils as the dominant fats (Chapter 6), and the rapid spread of glyphosate-based herbicides in commercial agriculture, beginning with the arrival of Roundup-tolerant genetically modified crops in 1996. Sweetener, fat and weed killer: a trio no grandmother would have put in her pantry.

The third. Each of these changes has produced real health consequences in the people eating the food. Glyphosate, in Dr. Mercola’s telling, harms the diversity of the gut’s bacteria, may disturb the hormones, and now turns up in much of the American food supply at levels that show up in nearly every consumer tested. (He calls it a carcinogen; as you will see below, the official verdict is still being argued, and I want you to know both sides.)

I walk through these changes one at a time, in this chapter and in Chapters 6 and 8, because the practical implications are significant, and because the reader who removes them from her diet will, in many cases, see improvements that no other intervention has produced. Sometimes the most powerful thing you can add to a diet is a subtraction.

This chapter is about the third change, and about the engineered crops that made it possible.

What a GMO Actually Is

A genetically modified organism, or GMO, is a plant or animal whose DNA has been altered in a laboratory by inserting genes from another species. Not in a field, not in a garden: in a laboratory.

That is not the same thing as the plant breeding farmers have always done. In traditional breeding, a farmer crosses related plants in the field and saves the seed of the best offspring. Over generations, the corn gets sweeter and the wheat stands taller. It is slow, patient work, measured in harvests. As The Ultimate Guide to GMOs on Mercola.com puts it, “In nature, breeding can only happen between related species.”

Genetic engineering crosses that line, and then keeps walking. A gene from a bacterium can be put into corn. A gene that no plant has ever carried can be forced into a soybean. And the guide is blunt about the method:

“the process of inserting a genetically modified gene into the DNA of a plant cell is crude, uncontrolled, and causes mutations (heritable changes) in the plant’s DNA blueprint.” (The Ultimate Guide to GMOs)

When a friend tells you, “GMOs are just like the plant breeding farmers have always done,” this is your answer. Traditional breeding crosses related plants in the field. Genetic engineering inserts genes from other species, such as bacteria, in a laboratory. One is matchmaking; the other is a transplant.

How Much of Our Food Is Engineered

You might think of GMOs as something exotic, something you would have to go looking for in a specialty shop. The opposite is true. You would have to go looking to avoid them.

The GMO guide reported that “up to 85 percent of U.S. corn, 91 percent of soybeans, and 88 percent of cotton are genetically modified,” and that “at least 80 percent of processed foods now contain genetically engineered ingredients.” Those figures have only grown since. Today well over 90% of U.S. corn, soy and cotton is genetically engineered. At this point the unmodified crop is the exotic one.

You rarely see these crops whole. They come to you in pieces, in disguise:

• Corn and soy become syrups, starches, flours, lecithin, protein isolates and oils, under more aliases than a spy novel.
• Cotton becomes cottonseed oil. Yes, the plant that makes your T-shirts also makes salad dressing.
• Canola is engineered too, and becomes canola oil.
• Sugar beets are engineered, so “sugar” on a label that does not say “cane sugar” is often from GMO beets.
• Alfalfa is engineered, and it feeds dairy cows.
• GMO corn and soy feed most conventional livestock, so they reach us through meat, milk and eggs as well, by the back door.

My rule of thumb is simple: if a food comes in a box and is not organic, it very likely contains GMOs. The box is usually the first clue.

Two Kinds of Engineering

Here is something most people never learn. For all the talk about what genetic engineering could do almost every GMO crop on the market has been changed in one of only two ways.

Crops that make their own insecticide. “Bt” corn and cotton carry a gene from the bacterium Bacillus thuringiensis, so every cell of the plant produces a toxin that bursts the guts of insects. The insect takes a bite and dies. We were told the toxin could not harm people. But the GMO guide reports research from Sherbrooke, Quebec, that found Bt toxins in the blood of pregnant women, and evidence that the toxin passes to the baby. A 2013 study in the Journal of Applied Toxicology found that Bt toxins were toxic to human cells in laboratory tests. So much for the toxin that only bothered bugs.

Crops that survive weed killer. “Roundup Ready” crops are engineered to tolerate glyphosate, the active ingredient in Roundup, so farmers can spray whole fields and kill everything except the crop. Soybeans came first, in 1996. Glyphosate-tolerant corn, cotton, canola, alfalfa and sugar beets followed, one after another. In the guide’s words:

“Genetically modified crops have been explicitly designed by biotech corporations to specifically tolerate and depend upon the very herbicides they sell and market to farmers.” (The Ultimate Guide to GMOs)

Read that sentence twice. The company that sold the seed also sold the spray, and the seed was designed to need it. That is not farming; that is a business model with roots.

This is why I tell my students that the herbicide sprayed on the crop may matter more to our health than the gene inserted into it. So let us turn to the herbicide.

Glyphosate: How a Weed Killer Got Into Our Food

Glyphosate is the active ingredient in Roundup, the herbicide developed by Monsanto and now sold by Bayer, which bought Monsanto in 2018. Glyphosate kills plants by blocking an enzyme (EPSP synthase) in a pathway plants use to build certain amino acids. That pathway is called the shikimate pathway. Remember that name; it will matter in a moment.

Until 1996, glyphosate could only be used as a weed killer sprayed before crops were planted, or where no crops grew at all, because it killed every green thing it touched. It did not play favorites. The engineered crops changed that. Once a crop could survive the spray, farmers could spray directly over the growing crop, again and again through the season. By the early 2010s, the dominant model of American farming was glyphosate-tolerant crops sprayed repeatedly during the growing season, carrying herbicide residues at harvest.

The numbers. Because the crops survive spraying, spraying increased dramatically. Give a farmer a crop that shrugs off the spray, and the spray gets used. The GMO guide reports that “more than 88,000 tons of glyphosate were used in the United States alone in 2007, up from 11,000 tons in 1992.” That is eight times as much in fifteen years.

It did not stop there. Agricultural economist Dr. Charles Benbrook used USDA data to show that herbicide-tolerant crops increased herbicide use by hundreds of millions of pounds. Nature does not stand still, and weeds do not read sales brochures. As weeds evolved resistance to glyphosate, farmers sprayed more, and stronger, chemicals.

Not only GMO crops. Here is the part that surprises even careful shoppers. Glyphosate is also sprayed on some non-GMO crops, such as wheat, oats, barley, lentils and peas, shortly before harvest. The spray kills the plants and dries them out evenly, so the seeds are easier to harvest by machine. Convenient for the combine; less convenient for your breakfast. This is called pre-harvest desiccation, and it has expanded a great deal since the early 2010s.

That is why glyphosate has been found in conventional oat cereals and bread, even though oats and wheat are not genetically engineered. Independent laboratories have found glyphosate residues in conventional wheat products, in most non-organic oats, and in many breakfast cereals, including cereals sold for children, cartoon mascots and all. It has been found in the urine of about eighty percent of Americans tested. The exposure is widespread, daily and cumulative, which is exactly the kind of exposure the Total Body Burden in Chapter 1 warns us about.

Organic farming does not allow glyphosate, either on the growing crop or before harvest. Not on the crop, not as a finishing touch.

Dr. Richard Schulze, the herbalist whose rule for healing runs through this whole book, put the whole problem in one sentence:

“It doesn’t make any sense to consume foods that are grown with poisons and sprayed with poisons, when you are trying to get the poisons OUT of your body.” (Dr. Richard Schulze)

Why It Matters to Us: The Gut and the Minerals

Monsanto, the company that made Roundup, long argued that glyphosate is harmless to people. Its reasoning sounded tidy, the kind of tidy that fits nicely in a press release: glyphosate blocks the shikimate pathway, and animals, including humans, do not have a shikimate pathway. No pathway, no harm.

But we are not only our own cells. We are also a crowd.

“Monsanto said that this sequence is absent in all animals. However, the shikimate pathway is present in the human gut bacteria.” (The Ultimate Guide to GMOs)

The friendly bacteria we depend on for digestion and immunity use the very pathway glyphosate shuts down. Our cells may lack the shikimate pathway, but our gut bacteria have it. A chemical designed to starve a plant of what it needs may do the same to the living garden inside us. Spray the weeds, and you may be weeding the wrong garden.

Dr. Stephanie Seneff, a senior research scientist at MIT, has published on glyphosate’s effects on gut bacteria and human health. She has linked those effects to a long list of modern illnesses, including digestive disease, allergies, autism, infertility and neurological disease. Her book Toxic Legacy lays out the case in full.

Glyphosate and minerals. There is a second reason to care. Glyphosate binds minerals. That is how it was first patented, as a descaling agent to clean mineral deposits out of pipes. Yes, pipes. A chemical that grabs minerals in a pipe may also grab them in the soil and in the food, making those minerals less available to the plant and to us. Not quite what you want sprinkled on your toast.

Researchers have also reported that glyphosate may interfere with the body’s own detoxification systems and act as an endocrine disruptor at low doses. The research is technical, and the implications are not fully worked out. But the pattern is clear enough that I want every reader of this book to take steps to reduce her exposure; I would rather be careful early than sorry late. And remember the simplest idea from Chapter 1: a toxin is anything that adds to the oxidative load the body must clear. Herbicides are on that list, near the top.

What the Research and the Courts Have Said

I want to be careful here not to overstate what has been proven, because your friends and clients will hear the other side, and you should hear it from me first, not across the table at Thanksgiving.

Here is what has happened:

• In 2015 the World Health Organization’s cancer agency, the International Agency for Research on Cancer (IARC), classified glyphosate as “probably carcinogenic to humans.” The classification rested largely on evidence linking it to non-Hodgkin lymphoma in agricultural workers.
• In 2020 Bayer, which bought Monsanto, agreed to pay about $10.9 billion to settle tens of thousands of lawsuits from people who developed non-Hodgkin lymphoma after using Roundup. Further cases have continued since.

The legal record, like the scientific record, is moving slowly, at the usual speed of courtrooms and committees. But it is moving.

The conventional view. I want you to be ready for the other side. The U.S. EPA and European food-safety regulators have concluded that glyphosate is not likely to cause cancer at expected exposures. A 2016 report from the U.S. National Academies of Sciences found no evidence that approved GMO foods are less safe to eat than conventional foods.

What the critics answer. Critics answer that much of the safety research was funded by the companies selling the products, which is a bit like letting the bakery judge its own pie contest. They point out that long-term human studies of a lifetime of exposure do not exist. And they say that the herbicide residue, not just the gene, is the issue, which is exactly what this chapter has been teaching. You learned in Chapter 1 to follow the money when you weigh an expert. This is a place to use that test, on both sides.

Know what each side says. Teach it fairly. And know this: choosing organic avoids both questions. You do not have to win the argument about the gene or the argument about the spray to protect your family from both. You can leave the debate running and simply walk around it.

Does It Feed the World?

The argument I hear most often for GMOs is that we need them to feed the world. It sounds compassionate, and it makes a lovely slogan. The evidence does not support it.

Dr. Doug Gurian-Sherman, in his 2009 report Failure to Yield, studied the question carefully and concluded:

“Commercial GE crops have made no inroads so far into raising the intrinsic or potential yield of any crop.” (Dr. Doug Gurian-Sherman, Failure to Yield, quoted in The Ultimate Guide to GMOs)

The crops were engineered to make insecticide and to survive weed killer. They were not engineered to produce more food. That was never the job description. And hunger, as the GMO guide reminds us, was never mainly a problem of too little food:

“the main reason for hunger is not lack of food at all, but a lack of access to it.” (The Ultimate Guide to GMOs)

There are other costs, too. The guide describes the cost to farmers, who must buy patented seed every year instead of saving their own, as farmers always have. Imagine having to rent your own harvest. Of one engineered crop, the guide says simply: “It did not increase farmers’ yields – only their debts.” And there is a cost to the creatures who share the fields with us. Bees and monarch butterflies lose their habitat and their food supply as weed-free monoculture spreads, mile after mile of one crop and nothing else growing, tidy to the eye and empty to a pollinator.

When someone tells you GMOs are needed to feed the world, you can answer gently: they have not raised the yield of any crop, hunger is mostly about access, and the farmers themselves have often been left poorer. No need to raise your voice; the facts are loud enough.

A Word on Milk: rBGH

One of the first genetically engineered products in our food was not a crop at all. It was rBGH, a synthetic growth hormone injected into dairy cows to increase milk production, as if the cows were not working hard enough already. It is banned in Canada, the European Union and many other countries.

The answer is not to give up dairy. It is to find better dairy: milk, butter and cheese from pasture-raised, hormone-free cows, ideally raw from a trusted local farm. Cows that eat grass are not eating GMO corn and soy, and their milk is different in its fats and its vitamins. A cow on a pasture is doing what a cow was made to do. Dr. Weston A. Price, whom you met in Chapter 1 and will meet fully in Chapter 13, found raw milk, butter and cheese from grass-fed cows among the treasured foods of the healthiest peoples he studied.

Shopping Around GMOs and Glyphosate

Now the practical work. Here is how I teach a family to avoid both the engineered crops and the weed killer sprayed on them, no lab coat required.

• Buy organic corn, soy, canola, sugar (or choose cane sugar), cotton products, papaya, oats and wheat. Certified organic food cannot be genetically engineered or sprayed with glyphosate, which makes it the one label that guarantees a food is neither. Words like “natural” and “farm fresh” promise nothing, however pretty the font.
• Look for the Non-GMO Project Verified seal on packaged foods. Know its limit: it covers GMOs, not glyphosate. A Non-GMO oat cereal may still have been sprayed before harvest. Organic covers both, two birds with one label.
• Read labels for corn and soy derivatives: corn syrup, corn starch, maltodextrin, soy lecithin, soy protein isolate, and processed vegetable oils like canola and cottonseed. The GMO guide lists “Processed vegetable oils like canola oil, rapeseed oil, and cottonseed oil” among the GMO-derived ingredients to avoid. (Those oils have problems of their own, enough to fill a whole chapter, which is exactly what they get in Chapter 6.)
• Buy from local farms. Grass-fed meat, pastured eggs and raw or rBGH-free dairy come from animals that eat grass, not GMO corn and soy. Buy from farmers you know when you can, and grow some of your own food if you can.
• Cook at home from whole ingredients. Most GMOs enter the diet through processed food. A pot of beans, a whole chicken and a pan of vegetables contain no corn syrup, no soy lecithin and no canola oil. They also come with no ingredient list to decode.
• Support the gut. Fermented foods such as sauerkraut, kefir and yogurt help rebuild the gut bacteria that glyphosate harms, restocking the garden after the spray. I say more about the gut and the body’s own detox work in Chapter 12, and about traditional fermented foods in Chapter 13.
• Use the produce lists. The Environmental Working Group’s Dirty Dozen and Clean Fifteen lists, updated every year, show which conventional fruits and vegetables carry the most pesticide residues and which carry the least. Buy organic first for the dirtiest, and save your money on the cleanest.

For the family on a tight budget. Families cannot buy everything organic overnight, and they do not need to. I hear it all the time: “Organic food is for rich people.” So I start with what costs least and matters most. For a family on a tight budget, the best first step is usually to cook more meals at home from whole ingredients. That one change removes most GMO ingredients and often saves money, which is the rare health tip that pays you back. Then buy organic first for the foods most often engineered or sprayed: oats, corn and soy products, sugar and canola. Buy conventional for low-risk produce. Buying in bulk, joining a local farm share or co-op, and cooking a pot of beans or a whole chicken stretch the budget further. Teach the children to read labels for corn, soy and canola; they make surprisingly good detectives. One change a month is a real victory.

As the GMO guide says, “Perhaps the most effective strategy you can do is to vote with your pocketbook.” Every time we choose the organic oats, the local eggs or the pot of beans, we choose life, for our own family and for the fields that feed it. The checkout line is a ballot box that is open every day.

The candle is in your hand. The kitchen is being cleaned. In the next chapter, we open the cupboard where the oils are kept. Bring a flashlight; some of those bottles have been hiding back there a long time.

Footnotes and sources for this chapter

Sources and Further Reading

• Mercola, J. The Ultimate Guide to GMOs. Special report, Mercola.com.
• Mercola, J. “Glyphosate” article series, Mercola.com.
• Mercola.com, Dr. Mercola’s website and newsletter.
• Gurian-Sherman, D. Failure to Yield. 2009.
• Seneff, S. Toxic Legacy: How the Weedkiller Glyphosate Is Destroying Our Health and the Environment. Chelsea Green, 2021.
• Benbrook, C. Analyses of USDA pesticide-use data on herbicide-tolerant crops.
• Research from Sherbrooke, Quebec, on Bt toxins in the blood of pregnant women, as reported in The Ultimate Guide to GMOs.
• 2013 study on the toxicity of Bt toxins to human cells, Journal of Applied Toxicology.
• International Agency for Research on Cancer (World Health Organization). Classification of glyphosate as “probably carcinogenic to humans,” 2015.
• U.S. National Academies of Sciences. Report on genetically engineered crops, 2016.
• Environmental Working Group. Testing reports on glyphosate in food, and the annual Dirty Dozen and Clean Fifteen lists.
• Martínez Steele, E., et al. “Ultra-Processed Foods and Added Sugars in the US Diet: Evidence from a Nationally Representative Cross-Sectional Study.” BMJ Open 6, no. 3 (2016): e009892.
• Seeds of Death (documentary on genetically engineered food).
• See Chapter 6 for the industrial seed oils, most of which come from GMO crops, and Chapter 13 for the traditional foods that replace the foods of modern commerce.