Wheat Belly. William Davis, MD

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СКАЧАТЬ you’re a farmer, encountering a pest feasting on your wheat field is a feared development. And there are many of them, from fungal rusts to wheat curl mites to sawflies. Farmers and agricultural geneticists therefore work to develop wheat strains that have better pest-resistant properties.

      Wheat comes with its own built-in pest-resistant protein called wheat germ agglutinin. The greater the wheat germ agglutinin content in a stalk of wheat, the greater its ability to fend off a pest trying to feast on it. After all, the plant cannot run away, or claw or bite the invader. When an insect eats a part of the wheat plant, wheat germ agglutinin attacks its gastrointestinal tract, either killing the creature or impairing its ability to generate offspring.

      Modern wheat strains have therefore been chosen for greater wheat germ agglutinin content.¹⁵ This peculiar protein is completely indigestible to humans: What goes in the mouth as a component of pretzels or crackers comes out unchanged in a bowel movement. As we shall discuss in the next chapter, in its course from mouth to toilet, however, wheat germ agglutinin acts as an exceptionally potent bowel toxin, essentially ripping apart the intestinal lining when given to experimental animals in pure form, less dramatically but still quite damagingly so when ingested as crust on pepperoni pizza. The small quantity that enters the bloodstream in humans amplifies inflammation and is hormonally disruptive. More on this to come.

      The enrichment of wheat germ agglutinin is yet another illustration that what’s good for the farmer and crop is not necessarily good for the consumer who feasts on onion bagels and penne pasta.

      In the future, the science of genetic modification (GM) has the potential to change wheat even further. No longer do scientists need to breed strains or expose seeds or embryos to toxic chemicals or gamma rays, cross their fingers, and hope for just the right mix of chromosomal change. Instead, single genes can be purposefully inserted or removed and strains bred for disease resistance, pesticide resistance, cold or drought tolerance, or any number of other genetically determined characteristics. In particular, new strains can be genetically tailored to be compatible with specific fertilizers or pesticides. This is a financially rewarding process for Big Agribusiness and seed and chemical producers such as Cargill, Monsanto, BASF, and ADM, since specific strains of seeds can be patent protected and thereby command a premium and boost sales of the compatible chemical treatments. While no strain of GM wheat is yet on store shelves, nearly all corn is genetically modified and, to a lesser degree, rice, cousins of our favorite grass-to-bash, wheat.

      Genetic modification is built on the premise that a single gene can be inserted in just the right place without disrupting the genetic expression of other characteristics. While the concept seems sound, it doesn’t always work out that cleanly. In the first decade of genetic modification, no animal or safety testing was required for genetically modified plants, since the practice was considered no different from the assumed-to-be-benign practice of hybridizing two strains of grasses. Public pressure has, more recently, caused regulatory agencies, such as the food-regulating branch of the FDA, to require testing prior to a genetically modified product’s release into the market. Critics of genetic modification, however, have cited studies that identify potential problems with genetically modified crops. Test animals fed glyphosate-tolerant soybeans show alterations in liver, pancreatic, intestinal, and testicular tissue compared to animals fed conventional soybeans. The difference is believed to be due to unexpected DNA rearrangement near the gene insertion site, yielding altered proteins in food with potential toxic effects, as well as the inclusion of herbicides tied to the GM crop such as glyphosate or the Bt toxin pesticide coded into the GM crop, now ingested by humans as hamburger buns and gluten-free cookies.¹⁶

      It took the introduction of gene modification to finally bring the notion of safety testing for genetically altered plants to light. Public outcry prompted the international agricultural community to develop guidelines, such as the 2003 Codex Alimentarius, a joint effort by the Food and Agricultural Organization of the United Nations and the World Health Organization, to decide what new genetically modified crops should be subjected to safety testing, what kinds of tests should be conducted, and what parameters should be measured.

      But no such outcry was raised years earlier as farmers and geneticists carried out tens of thousands of hybridization and chemical mutagenesis experiments. There is no question that unexpected genetic rearrangements that might generate some desirable property, such as greater drought resistance or better dough properties, can be accompanied by changes in proteins that are not evident to the eye, nose, or tongue, but little effort has focused on these side phenomena. Hybridization and other efforts continue, breeding new “synthetic” wheat. While they fall short of the precision of gene modification techniques, they still possess the potential to inadvertently “turn on” or “turn off” genes unrelated to the intended effect, generating unique characteristics, not all of which are presently identifiable.¹⁷

      Thus, alterations of wheat that could potentially result in undesirable effects on humans are not due to gene insertion or deletion, but are due to manipulations that predate genetic modification. As a result, over the past sixty years, thousands of new wheat strains have made it to the commercial food supply and supermarket shelves without a single effort at safety testing. This is a development with such enormous implications for human health that I will repeat it: Modern wheat, despite all the genetic alterations to modify thousands of its genetically determined characteristics, made its way to the worldwide human food supply with nary a question surrounding its suitability for human consumption.

      Because hybridization experiments did not require the documentation of animal or human testing, pinpointing where, when, and how the precise hybrids that might have amplified the ill effects of wheat is an impossible task.

      The incremental genetic variations introduced with each effort at “improving” wheat strains can make a world of difference. Take human males and females. While men and women are, at their genetic core, largely the same, the differences clearly make for interesting conversation, not to mention romantic moments in dark corners. The crucial differences between human men and women, a set of differences that originate with just a single chromosome, the diminutive male Y chromosome and its few genes, set the stage for thousands of years of human life and death, Shakespearean drama, and the chasm separating Homer from Marge Simpson.

      And so it goes with this human-engineered grass we still call “wheat.” Genetic differences generated via thousands of human-engineered manipulations make for substantial variation in composition, appearance, and qualities important not just to chefs and food processors, but also to human health.

       CHAPTER 3

       WHEAT DECONSTRUCTED

      WHETHER IT’S A loaf of organic high-fiber multi-grain bread or a Twinkie, what exactly are you eating? We all know that the Twinkie is just a processed indulgence, but conventional advice tells us that the former is a better health choice, a source of fiber and B vitamins, rich in “complex” carbohydrates, and your ticket to a life of slenderness and freedom from diabetes, heart disease, and colon cancer.

      Ah, but there’s always another layer to the story. Let’s peer inside the contents of this grain and try to understand why—regardless of shape, color, fiber content, organic or not—it potentially does peculiar and harmful things to humans.

      WHEAT: SUPERCARBOHYDRATE

      The transformation of domesticated wild grass of Neolithic times into modern Cinnabon rolls, French crullers, or Dunkin’ Donuts requires some serious sleight of hand. These modern configurations were not possible with the dough of ancient wheat.

      An СКАЧАТЬ