Wheat Belly Total Health: The effortless grain-free health and weight-loss plan. Dr Davis William
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or table sugar.
For years, we’ve been told that ‘complex’ carbohydrates are better for us than ‘simple’ sugars because the lengthy carbohydrate molecules of amylopectin A and amylose in grains don’t raise blood sugar as high as sugars with one or two sugar molecules, such as glucose (one sugar) or sucrose (two sugars: glucose and fructose), do. But this is simply wrong, and this silly distinction is therefore being abandoned: the GI of complex carbohydrates is the same as or higher than that of simple sugars. The GI of whole wheat bread: 72; the GI of millet as a hot cereal: 67. Neither are any better than the GI of sucrose: 59 to 65. (Similar relationships hold for the glycaemic load, a value that factors in typical portion size.) The World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations have both advised dropping the complex versus simple distinction, and rightly so, as grains, from a blood sugar viewpoint, are the same as or worse than sugar.
And the problems with non-wheat grains don’t end with blood sugar issues.
Lectins: Good Enough for the KGB
The lectin proteins of grains are, by design, toxins. Lectins discourage creatures, such as moulds, fungi and insects, from eating the seeds of a plant by sickening or killing them. After all, the seed is the means by which plants continue their species. When we consume plants, we consume defensive lectins. Lectin proteins’ effects on humans vary widely, from harmless to fatal. Most plant lectins are benign, such as those in spinach and white mushrooms, which cause no adverse effects when consumed as a spinach salad. The lectin of castor beans is an entirely different story; its lectin, ricin, is highly toxic and is fatal even in small quantities. Ricin has been used by terrorists around the world. Gyorgy Markov, Bulgarian dissident and critic of the Soviet government, was murdered by KGB agents in 1978 when he was poked with the tip of an umbrella laced with ricin.
The lectin of the seed of wheat is wheat germ agglutinin (WGA). It is neither as benign as the lectin of spinach nor as toxic as the lectin of ricin; it is somewhere in between. WGA wreaks ill effects on everyone, regardless of whether you have coeliac disease, gluten sensitivity or no digestive issues at all. The lectins of rye, barley and rice are structurally identical to WGA and share all of its properties and are also called ‘WGA’. (The only substantial difference is that rye, barley and rice express a single form of lectin, while genetically more complex wheat expresses up to three different forms.) Interestingly, 21 per cent of the amino acid structure of WGA lectins overlaps with ricin, including the active site responsible for shutting down protein synthesis, the site that accounts for ricin’s exceptional toxicity.1
Lectin proteins have the specific ability to recognize glycoproteins (proteins with a sugar side chain). This makes plant lectins effective in recognizing common glycoproteins on, say, the surface of a fungal cell. But that same process can occur in humans. When a minute quantity, such as 1 milligram, of WGA is purified and intestinal tissue is exposed to it, intestinal glycoproteins are bound and severe damage that resembles the effects of coeliac disease results.2 We also know that WGA compounds the destructive intestinal effects of coeliac disease started by gliadin and other grain prolamin proteins.3 If you have inflammatory bowel disease, ulcerative colitis, or Crohn’s disease, grain lectins intensify the inflammation, making cramps, diarrhoea, bleeding and poor nutrient absorption worse.
WGA is oddly indestructible. It is unaffected by cooking, boiling, baking or frying. WGA is also untouched by stomach acid. Though the acid produced in the human stomach is powerfully corrosive (dip your finger in a glass full of stomach acid and you won’t have a finger for very long), WGA is impervious to it, entering the stomach and passing through the entire gastrointestinal tract unscathed, undigested and free to do what it likes to any glycoproteins exposed along the way.
While most WGA remains confined to the intestine, doing its damage along the 30-foot length of this organ, we know that a small quantity gets into your bloodstream. (We know this because people commonly develop antibodies to this protein.) Once WGA enters the bloodstream, odd things happen: red blood cells clump (or ‘agglutinate’, the basis for WGA’s name), which can, under certain circumstances (obesity, smoking, sedentary living, dehydration, etc.), increase the tendency of blood to clot – the process that leads to heart attack and stroke. WGA is often called a mitogen because it activates cell division, or mitosis (a concept familiar to anyone who studies cancer, a disease characterized by unrestrained mitosis). WGA has indeed been demonstrated to cause mitosis in lymphocytes (immune system cells) and cells lining the intestine.4 We know that such phenomena underlie cancer, such as the intestinal lymphoma that afflicts people with coeliac disease.5 WGA also mimics the effects of insulin on fat cells. When WGA encounters a fat cell, it acts just as if it were insulin, inhibiting activation of fat release and blocking weight loss while making the body more reliant on sugar sources for energy.6 WGA also blocks the hormone leptin, which is meant to shut off appetite when the physical need to eat has been satisfied. In the presence of WGA, appetite is not suppressed, even when you’re full.7
All in all, grain lectins are part of a potent collection of inflammatory factors. Indigestible or only partially digestible, they fool receptors and thwart hormonal signals after gaining entry to our bodies through the seeds of grasses.
VIP: Very Important Peptide
The lectin found in wheat, rye, barley and rice (WGA) also blocks the action of another very important hormone called vasoactive intestinal peptide, or VIP. 8 While studies have been confined mostly to experimental models, not humans, the blocking of VIP has the potential to explain many of the peculiar phenomena that develop in people who consume grains but do not have coeliac disease or gluten sensitivity.
VIP plays a role in dozens of processes. It is partly responsible for:
• Activating the release of cortisol from the adrenal glands9
• Modulating immune defences against bacteria and parasites in the intestine10
• Protecting against the immune destruction of multiple sclerosis11
• Reducing phenomena that can lead to asthma and pulmonary hypertension (increased pressure in the lungs)12
• Maintaining healthy balance of the immune system that prevents inflammatory bowel diseases, Crohn’s disease and ulcerative colitis13
• Promoting sleep and maintaining circadian rhythms (day–night cycles)14
• Participating in determining taste in the tongue15
• Modulating the immune and inflammatory response in skin that protects us from psoriasis16
In other words, the diseases that are at least partially explained by blocking VIP sure look and sound like the collection of conditions that we witness, day in, day out, in wheat-consuming people: low cortisol levels responsible for low energy, worsening of asthma and pulmonary hypertension, worsening of Crohn’s disease and ulcerative colitis, disruption of sleep, distortions of taste such as the reduced sensitivity to sweetness (meaning you need more sugar for sweetness) and psoriasis. The VIP pathway may prove to be one of the important means by which grains disrupt numerous aspects of health.
Grains and a Mouthful of Bacteria
Grains affect the microorganisms that inhabit our bodies. These microbiota live on your skin and in your mouth, vagina and gastrointestinal tract.
Over the last few years, there has been a new scientific appreciation for the composition of human microbiota. We know, for instance, that experimental animals raised in an artificial sterile environment and thereby raised with a gastrointestinal tract that contains no microorganisms have impaired immunity, are prone to infections, are less efficient at digestion and even develop structural changes of the gastrointestinal tract that differ from creatures that harbour plentiful microorganisms. The microorganisms that inhabit our bodies are not only helpful; they are essential for health.
The bacteria that share in this symbiotic relationship with our bodies today are not the same as those carried by our ancestors. Human microorganisms underwent a