Wheat Belly Cookbook: 150 delicious wheat-free recipes for effortless weight loss and optimum health. Dr Davis William

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СКАЧАТЬ there are obvious outward changes visible to the naked eye. The knee-high semi-dwarf plant has a shorter stalk that diverts less fertilizer and nutrients from the seeds. This change in height is due to changes in Rht (reduced height) genes that code for the protein gibberellin, controlling stalk length (discussed later). The seedhead is larger, with seeds that are also bigger and different in shape. While there is variation among the 25,000 modern strains, semi-dwarf wheat also tends to have reduced protein content and higher carbohydrate content, and it yields different baking and texture characteristics.

      The differences in outward appearance are accompanied by internal genetic and biochemical differences.

      Gliadin

      Gliadin is among the most interesting – and most destructive – of all the many components of modern wheat.

      Gliadin is one of the proteins in the gluten family of proteins. Gluten is actually a combination of smaller gliadin proteins and lengthier glutenin molecules. While gluten is often fingered as the source of wheat’s problems, it’s really gliadin that is the culprit behind many health issues.

      Gliadin can assume many forms, with more than 200 gene variants coding for as many variations of gliadin protein. The past 50 years of genetics research has introduced extensive changes into gliadin structure, but the full implications of these changes have not been fully mapped out, as they were assumed to be benign. And, after all, this research was performed by agricultural scientists, not doctors or people with insights into human health. Changes in gliadin have therefore been dismissed as harmless, despite the fact that gliadin is capable of increasing intestinal ‘leakiness’ to foreign proteins and triggering cross-reactions with human structures (i.e., triggering an abnormal immune response to similar, though not identical, proteins in the body, a process called molecular mimicry), such as nervous system proteins like synaptin, cells of the intestinal lining (enterocytes) or the ubiquitous calcium-modulating protein calreticulin, potentially triggering inflammatory and immune responses to these proteins.

The changes introduced over the past 50 years in particular have increased the expression of the Glia-α9 amino acid sequence within gliadin that has been most closely linked to triggering coeliac disease. While the genetic sequence coding for Glia-α9 was absent from most strains of wheat from the 19th and early 20th centuries, it is now present in nearly all modern varieties. Glia-α9 is a perfect fit for the transglutaminase enzyme that activates it into the form that strongly binds immune-activating (‘HLA DQ’) molecules lining the intestinal wall, activating the characteristic T-cell immune response that sets coeliac disease in motion. The dramatically increased presence of Glia-α9 likely explains why there has been a fourfold increase in coeliac disease since 1948. (Interestingly, the Glia-α9 sequence, coded for on the sixth chromosome of the ‘D’ collection of genes in modern wheat, is also absent from primitive strains of wheat that lack ‘D’ genes, such as einkorn, which contains only the ‘A’ set of genes, and emmer, which contains the ‘A’ and ‘B’ sets of genes.)

      Opiates, such as heroin, have been shown to activate appetite in addition to pain relief and euphoria. Likewise, the new forms of wheat gliadin have been shown to have effects on the human brain via binding to opiate receptors – yes, opiate receptors, the very same receptors that are activated by heroin, morphine and Oxycontin. The opiate-like effects of wheat gliadin, however, are less of a ‘high’ and more that of increased appetite and increased calorie consumption, with studies demonstrating a very consistent increased calorie intake of 400 or more calories per day (see ‘Wheat Gliadin and Exorphins: The Ultimate Obesogens’). Blocking gliadin with opiate-blocking drugs like naloxone and naltrexone has been shown to reduce calorie consumption by 400 calories per day and induce weight loss of 1 stone 11 pounds over 6 to 12 months.

      Glia-α9 represents just one change introduced into so-called α-gliadins. Changes have also been introduced into the three other fractions of gliadin, including the Ω-gliadin responsible for some forms of wheat allergy and anaphylaxis, and γ-gliadin that, along with the α form, bind HLA DQ. The full effect of these changes, given the widely held assumption that wheat is good for health, has not been fully explored.

      Gluten

      Gluten is the stuff that confers the viscoelastic properties that are unique to wheat dough, the stretchability and mouldability that allow it to be so accommodating to bakers and shapeable into so many varied configurations, from pretzels to pizza. Gluten is also popular as an additive to processed foods like sauces, instant soups, and frozen foods, causing the average person to ingest from 15 to 20 grams per day.

      Gluten is a diverse collection of proteins that vary from wheat strain to wheat strain. Gluten is the recipient of much genetic manipulation, as the long chain and branching structure of the glutenin proteins within gluten determine baking characteristics (firmness, sturdiness, bendability, stretchability, crust formation). Geneticists therefore bred and crossbred wheat strains repeatedly to achieve desired baking characteristics, bred wheat with non-wheat grasses to introduce new genes, and used chemicals and radiation to induce mutations that included new and unique changes in glutenin characteristics.

      In addition to adding lightness to doughnuts and chewiness to wraps, gluten is also among the most destructive of proteins in the human diet, thanks to its ability to bind to what are called HLA DQ proteins (via gliadin) along the insides of the human intestinal tract. People with specific genetically determined forms of the HLA DQ proteins, such as DQ2 and DQ8, are especially prone to this effect, yielding inflammatory responses that result in coeliac disease or sensitivity to gluten. Up to 30 per cent of the population has either the DQ2 or DQ8 genes – by no means rare, though only around 1 per cent of people with either DQ gene will develop the full-blown coeliac disease syndrome, while another 10 per cent develop gluten sensitivity. (It’s not entirely clear why some people develop gluten sensitivity with symptoms of abdominal cramps, gas, diarrhoea, etc., while others develop more severe coeliac disease.)

      Other important changes have been introduced into gliadin proteins of gluten (see here), including enrichment of the more harmful Glia-α9 sequences that likely underlies the quadrupling of coeliac disease over the past 50 years.

Wheat Gliadin and Exorphins: The Ultimate Obesogens

      Obesity research has raised an intriguing question: Are we being exposed to industrial chemicals that cause weight gain and contribute to the obesity epidemic? Bisphenol A (BPA), which is found in polycarbonate plastics and the resin lining of cans, and the pesticide atrazine, for instance, are two compounds suspected to provoke weight gain by blocking or distorting various glandular responses. These chemicals have been dubbed obesogens – compounds that cause obesity.

      Could something new in wheat also be an obesogen?

      The gliadin proteins of wheat are degraded in the gastrointestinal tract to a group of polypeptides named exorphins, or exogenously derived morphine-like compounds. Several different exorphin compounds, called gluteomorphin or gliadorphins by researchers studying these curious compounds over the last 30 years, have been identified. Not only do wheat-derived exorphins bind to the brain’s opiate receptors, but they are blocked from interacting with brain opiate receptors by the opiate-blocking drugs naloxone and naltrexone, the very same drugs used as antidotes, for example, for heroin or narcotic overdose.

      So what is the evidence that the opiate-binding compounds that derive from wheat gliadin, in particular the newest forms of gliadin in modern wheat, via wheat exorphins, stimulate appetite? Here’s a sampling of the research.

      • Coeliac disease, intestinal destruction from wheat gluten/gliadin, is traditionally regarded as a condition yielding emaciated, malnourished people, but has, over the last 40 years, become a disease СКАЧАТЬ