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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 attempt to make a modern jelly donut with einkorn wheat, for example, would yield a crumbly mess that would not hold its filling, and it would taste, feel, and look like, well, a crumbly mess. In addition to breeding wheat for increased yield, geneticists have also sought to generate strains with properties best suited to become, for instance, a chocolate sour cream cupcake or a seven-tiered wedding cake.

Modern Triticum aestivum wheat flour is, on average, 70 percent carbohydrate by weight, with protein and indigestible fiber each comprising 10 to 15 percent. The small remaining weight of Triticum wheat flour is fat, mostly phospholipids and polyunsaturated fatty acids.¹ (Interestingly, ancient wheat has higher protein content. Emmer wheat, for instance, contains 28 percent or more protein.)²

Wheat starches are the complex carbohydrates that are the darlings of dietitians. “Complex” means that the carbohydrates in wheat are composed of polymers (repeating chains) of the simple sugar, glucose, unlike simple carbohydrates such as sucrose that are one- or two-unit sugar structures. (Sucrose is a two-sugar molecule, glucose + fructose.) Conventional wisdom, such as that from your dietitian or the USDA, says we should all reduce our consumption of simple carbohydrates in the form of candy and soft drinks, and increase consumption of complex carbohydrates.

Of the complex carbohydrate in wheat, 75 percent is the chain of branching glucose units, amylopectin, and 25 percent is the linear chain of glucose units, amylose. In the human gastrointestinal tract, both amylopectin and amylose are digested by the salivary and stomach enzyme amylase. Amylopectin is efficiently digested by amylase to glucose, while amylose is much less efficiently digested, some of it making its way to the colon undigested. Thus, the complex carbohydrate amylopectin is rapidly converted to glucose and absorbed into the bloodstream and, because it is most efficiently digested, is mainly responsible for wheat’s blood-sugar-increasing effect.

Other carbohydrate foods also contain amylopectin, but not the same kind of amylopectin as wheat. The branching structure of amylopectin varies depending on its source.³ Amylopectin from legumes, so-called amylopectin C, is the least digestible. Undigested amylopectin C makes its way to the colon, whereupon the symbiotic bacteria happily dwelling there feast on the undigested starches and generate gases such as nitrogen and hydrogen—hence the schoolkids’ chant, “Beans, beans, they’re good for your heart, the more you eat, the more you …”—making the sugars unavailable for you to digest but forcing you to excuse yourself from a business meeting.

Amylopectin B is the form found in bananas and potatoes and, while more digestible than bean amylopectin C, still resists digestion to some degree. The most digestible form of amylopectin, amylopectin A, is the form found in wheat and its grain brethren. Because it is the most digestible, it is the form that most enthusiastically increases blood sugar. This explains why, gram for gram, wheat increases blood sugar to a greater degree than kidney beans or potato chips. The amylopectin A of wheat products, complex or no, is a supercarbohydrate, a form of highly digestible carbohydrate that is more efficiently converted to blood sugar than nearly all other carbohydrate foods, simple or complex.

This means that not all complex carbohydrates are created equal, with amylopectin A–containing wheat increasing blood sugar more than other complex carbohydrates. The uniquely digestible amylopectin A of wheat also means that the complex carbohydrate of wheat products, on a gram-for-gram basis, are no better, and are often worse, than simple carbohydrates such as sucrose.

People are often shocked when I tell them that whole wheat bread increases blood sugar to a higher level than sucrose.⁴ Aside from some extra fiber, eating two slices of whole wheat bread is really little different, actually worse, than drinking a can of sugar-sweetened soda or eating a sugary candy bar.

This information is not new. A 1981 University of Toronto study launched the concept of glycemic index, i.e., the comparative blood sugar effects of carbohydrates: the higher the blood sugar after consuming a specific food compared to glucose, the higher the glycemic index (GI). The original study showed that the GI of white bread was 69, while the GI of whole grain bread was 72 and Shredded Wheat cereal was 67, while that of sucrose (table sugar) was 59.⁵ Yes, the GI of whole grain bread is higher than that of sucrose. Incidentally, the GI of a Mars bar—nougat, chocolate, sugar, caramel—is 68. That’s better than whole grain bread. The GI of a Snickers bar is 41—far better than whole grain bread.

In fact, the degree of processing, from a blood sugar standpoint, makes little difference: Wheat is wheat, with various forms of processing or lack of processing, simple or complex, high-fiber or low-fiber, organic or non-organic, all generating similarly high blood sugars. Just as “boys will be boys,” amylopectin A will be amylopectin A. In healthy, slender volunteers, two medium slices of whole wheat bread increase blood sugar by 30 mg/dl (from 93 to 123 mg/dl), no different from white bread.⁶ In people with diabetes, both white and whole grain bread increase blood sugar 70 to 120 mg/dl over starting levels.⁷

One consistent observation, also made in the original University of Toronto study as well as in subsequent efforts, is that pasta has a lower two-hour GI, with whole wheat spaghetti showing a GI of 42 compared to white flour spaghetti’s GI of 50. Pasta stands apart from other wheat products, likely due, in part, to the compression of the wheat flour that occurs during the extruding process, slowing digestion by amylase. (Rolled fresh pasta, such as fettuccine, has similar glycemic properties to extruded pastas.) Pastas are also usually made from Triticum durum rather than aestivum, putting them genetically closer to emmer. But even the favorable GI rating of pasta is misleading, since it is only a two-hour observation and pasta has the curious ability to generate high blood sugars for four to six hours after consumption, sending blood sugars up by 100 mg/dl for sustained periods in people with diabetes.^{8, 9}

These irksome facts have not been lost on agricultural and food scientists, who have been trying, via genetic manipulation, to increase the content of so-called resistant starch (starch that does not get fully digested) and reduce the amount of amylopectin. Amylose is the most common resistant starch, increased to as much as 40 to 70 percent by weight in some purposefully hybridized varieties of wheat.¹⁰

Wheat products therefore elevate blood sugar levels more than virtually any other carbohydrate, from beans to candy bars. This has important implications for body weight, since glucose is unavoidably accompanied by insulin, the hormone that allows entry of glucose into the cells of the body, converting glucose to fat. The higher the blood glucose after consumption of food, the greater the insulin level, the more fat is deposited. This is why, say, eating a three-egg omelet that triggers no increase in glucose does not add to body fat, while two slices of whole wheat bread increases blood glucose to high levels, triggering insulin and growth of fat, particularly abdominal or deep visceral fat.

There’s even more to wheat’s curious glucose behavior. The amylopectin A–induced surge in glucose and insulin following wheat consumption is a 120-minute-long phenomenon that produces the “high” at the glucose peak, followed by the “low” of the inevitable glucose drop. The surge and drop creates a two-hour roller coaster ride of satiety and hunger that repeats itself throughout the day. The glucose “low” is responsible for stomach growling at 9:00 a.m. that necessitates a snack, just two hours after a bowl of wheat cereal or an English muffin breakfast, followed by 11:00 a.m. prelunch cravings, as well as the mental fog, fatigue, and shakiness of the hypoglycemic glucose nadir.

Trigger high blood sugars repeatedly and/or over sustained periods, and more fat accumulation results. The consequences of glucose-insulin-fat deposition are especially visible in the abdomen—resulting in, yes, wheat belly. The bigger your wheat belly, the poorer your response to insulin, since the deep visceral fat of the wheat belly is associated with poor responsiveness, or “resistance,” to insulin, demanding higher and higher insulin levels, a situation that cultivates diabetes. Moreover, the bigger the wheat belly in males, the more testosterone is converted to estrogen by fat tissue, and the larger the breasts. In susceptible females, testosterone is increased, accompanied by facial hair and infertility. The bigger your wheat belly, the more inflammatory responses that are triggered: heart disease, cancer, and dementia.

Because of wheat’s morphine-like effect (discussed in the next chapter) and the glucose-insulin cycle that wheat amylopectin A generates, wheat is, in effect, an appetite stimulant. Accordingly, people who eliminate wheat from their diet consume far fewer calories, something I will discuss later in the book.

If glucose-insulin-fat provocation from wheat consumption is a major phenomenon underlying weight gain, then elimination of wheat from the diet should reverse the phenomenon. And that is exactly what happens.

For years, wheat-related weight loss has been observed in patients with celiac disease, who must eliminate all foods containing gluten from their diets to halt an immune response gone awry, which in celiac patients essentially destroys the small intestine. As it happens, wheat-free, gluten-free diets are also amylopectin A–free, especially if other grains are eliminated.

However, the weight loss effects of wheat elimination are not immediately clear from clinical studies. Many celiac sufferers are diagnosed after years of suffering and begin the diet change in a severely malnourished state due to prolonged diarrhea and impaired nutrient absorption. Underweight, malnourished celiac sufferers may actually gain weight with wheat removal thanks to improved digestive function.

Wheat Belly Success Story: Kathleen

“Just came back from my annual physical, where I managed to shock the bejeezus out of my doctor, which is not an easy thing to do.

“She looked at my vitals and last year’s report, looked at me, and said in complete surprise, ‘What have you been doing?! What happened to last year’s issues?’ Meaning dangerously low blood pressure, heart palpitations, GERD (gastroesophageal reflux disease), Barrett’s esophagitis (a nasty little swallowing disorder), leg edema, unstoppable weight gain/BMI in the obese range, chronic fatigue and brain fog, and zero libido to be the frosting on that little cake of unpleasantness.

“All of those issues have completely resolved, BMI normal and healthy, and my blood pressure has actually increased to normal. I’ve always had very low blood pressure, which caused fainting spells, edema, and heart palpitations. I’ve actually passed out right in front of her during exams in the past. Haven’t had any of those issues since starting this way of eating eleven months ago.

“The ‘before’ was taken during a time when I was doing CrossFit three times a week, spin classes three times a week, and riding my bicycle hundreds of miles a week (yes, every week) to train for hundred-mile charity bike rides. All the while eating low-fat and ‘healthy’ whole grains and barely losing any weight. Would you just look at that butt! My doctor told a frustrated me that I just needed to exercise more and it would come off. I asked her what more could I do, wrestle a bear?!

“The ‘after’ is me eighty pounds lighter after eighteen months grain-free. The cardiac issues are gone. And recovering from a broken ankle and being confined to a walking boot for almost two months. The muscles that I’ve worked so hard to build for years are finally showing. I’m fifty-three-and-a-half and am here to show that it’s never too late to get your health back and you’re never too old to start living! Soldier on, Wheat Belliers, and let your inner jock come out to play!”

But if we look only at overweight people who are not severely malnourished at the time of diagnosis who remove wheat from their diet, it becomes clear that this enables them to lose a substantial amount of weight. A Mayo Clinic/University of Iowa study of 215 obese celiac patients showed 27.5 pounds of weight loss in the first six months of a wheat-free diet.¹¹ In another study, wheat elimination slashed the number of people classified as obese (body mass index, or BMI, 30 or greater) in half within a year.¹² Oddly, investigators performing these studies usually attribute the weight loss of wheat- and gluten-free diets to lack of food variety. (Food variety, incidentally, can still be quite wide and wonderful after wheat is eliminated, as I will discuss.)

Advice to consume more healthy whole grains therefore causes increased consumption of the amylopectin A form of wheat carbohydrate, a form of carbohydrate that, for all practical purposes, is little different, and in some ways worse, than dipping your spoon into the sugar bowl.

GLUTEN: WE HARDLY KNOW YA!

If you were to add water to wheat flour, knead the mixture into dough, then rinse the glob under running water to wash away starches and fiber, you’d be left with a protein mixture called gluten.

Wheat is the principal source of gluten in the diet, both because wheat products have come to dominate and because most Americans do not make a habit of consuming plentiful quantities of barley, rye, bulgur, kamut, spelt, einkorn, emmer, or triticale, the other sources of gluten. For all practical purposes, therefore, when I discuss gluten, I am primarily referring to wheat.

While wheat is, by weight, mostly amylopectin A carbohydrate, gluten protein is what makes wheat “wheat.” Gluten is the unique component of wheat that makes dough “doughy”: stretchable, rollable, spreadable, twistable, baking gymnastics that cannot be achieved with rice flour, corn flour, or any other grain. Gluten allows the pizza maker to roll and toss dough and mold it into the characteristic flattened shape; it allows the dough to stretch and rise when yeast fermentation causes it to fill with air pockets. The distinctive doughy quality of the simple mix of wheat flour and water, properties food scientists call viscoelasticity and cohesiveness, are due to gluten. While wheat is mostly carbohydrate and only 10 to 15 percent protein, 80 percent of that protein is gluten. Wheat without gluten would lose all its unique qualities that transform dough into bagels, pizza, or focaccia.

Glutens are the storage proteins of the wheat plant, a means of storing carbon and nitrogen for germination of the seed to create new wheat plants. Leavening, the “rise” process created by the marriage of wheat with yeast, does not occur without gluten, and is therefore unique to wheat flour.

The term “gluten” encompasses two primary families of proteins, the gliadins and the glutenins. Gliadins, the protein group that most vigorously triggers the immune response in celiac and other diseases, has three subtypes: α/β-gliadins, γ-gliadins, and ω-gliadins. Importantly, gliadin proteins are responsible for effects beyond celiac disease, such as initiating autoimmune diseases, direct intestinal injury, and opiate effects on the brain, effects we shall discuss later. Glutenin proteins are long repeating structures, or polymers, of more basic units. The strength of dough is due to the large polymeric glutenins, a genetically programmed characteristic purposefully selected by plant breeders.¹³ Glutenins are likewise a source of health problems for unwitting humans consuming them.

Gluten from one wheat strain can be quite different in structure from that of another strain. Gluten proteins produced by einkorn wheat, for example, are distinct from the gluten proteins of emmer, which are, in turn, different from the gluten proteins of the thousands of strains of Triticum aestivum.^{14, 15} Because fourteen-chromosome einkorn has the smallest chromosomal set, it codes for the fewest number and variety of glutens. Twenty-eight-chromosome emmer codes for a larger variety of gluten. Forty-two-chromosome Triticum aestivum has the greatest gluten variety, even before any human manipulation. Breeding efforts of the past sixty years have generated numerous additional changes in gluten-coding genes in Triticum aestivum.¹⁶ Because breeding efforts focus only on agricultural and baking interests and not on human health, genes contained in modern wheat are most frequently pinpointed as the source of glutens that trigger celiac disease, effects amplified compared to traditional strains.¹⁷

It is therefore modern Triticum aestivum that, having been the focus of all manner of genetic shenanigans by geneticists, has accumulated substantial changes in genetically determined characteristics of gliadin and glutenin proteins within gluten. It is also the source for many of the other odd health phenomena experienced by consuming humans.

In celiac disease, the one conventionally accepted (though miserably underdiagnosed) example of wheat-related intestinal illness, gliadin proteins, specifically α-gliadin, provoke an immune response that inflames the small intestine, causing abdominal cramps and diarrhea. Treatment is simple: complete avoidance of anything containing gluten. Unfortunately, this association has caused most people, including doctors, to believe that the only problem with wheat and grains is gluten when there are actually dozens of toxic compounds in the seeds of grasses.

The “wheat is only a gluten problem” has blinded many people into thinking that, if you don’t have celiac disease, then eating all the ciabattas, donut holes, and tortellini you want is actually healthy. It has led to silly research efforts such as those conducted at Monash University in Australia in which purified gluten was administered to people with presumed non-celiac gluten intolerance and the majority (92 percent) tolerated it without gastrointestinal consequences, causing the authors to declare that gluten is not a problem for most people.¹⁸ Removing nicotine from cigarettes does not make smoking healthy. Tolerating purified gluten over a brief period of observation does not negate the potential for long-term harm, such as autoimmune diseases or brain effects, not to mention the harmful consequences of the dozens of other components besides gluten.

Did you want a low-tar cigarette with that salami sandwich?

IT’S NOT ALL ABOUT GLUTEN

You now know that gluten isn’t the only potential villain lurking in wheat flour.

Beyond gluten, the other 20 percent or so of non-gluten proteins in wheat include albumins, prolamins, and globulins, each of which can also vary from strain to strain. In total, there are more than a thousand other proteins that are meant to serve such functions as protecting the grain from pests, providing water resistance, and supplying reproductive functions. There are agglutinins, peroxidases, α-amylases, serpins, and acyl CoA oxidases, not to mention five forms of glyceraldehyde-3-phosphate dehydrogenases. I shouldn’t neglect to mention β-purothionin, puroindolines a and b, and starch synthases. Wheat ain’t just gluten, any more than southern cooking is just grits.

Let’s take just one of these non-gluten proteins, wheat germ agglutinin, which has been enriched in modern strains of wheat through breeding to take advantage of its pest-resistant effects, making a stalk of wheat more resistant to fungi and molds. Wheat germ agglutinin is completely indigestible to humans, passing through the entire gastrointestinal tract unfazed by stomach acid, thumbing its nose at digestive enzymes and bile, eventually exiting into the toilet. But, in its travels from swallow to flush, it wreaks gastrointestinal havoc. One milligram (just a speck—there are 4,000 milligrams in just one packet of sugar) of purified wheat germ agglutinin fed to a laboratory animal results in extensive damage to the intestinal lining.¹⁹ While grains such as ancient wheat, rye, barley, and rice contain a single form of wheat germ agglutinin, modern wheat contains three different varieties, given its heightened genetic pliability. And this is just one protein among many beyond gluten in wheat and related grains.

There are also allergic or anaphylactic (a severe allergic reaction resulting in shock) reactions to non-gluten proteins, including α-amylases, thioredoxin, and glyceraldehyde-3-phosphate dehydrogenase, along with about a dozen others.²⁰ Exposure in susceptible individuals triggers asthma, rashes (eczema and hives), and a curious and dangerous condition called wheat-dependent exercise-induced anaphylaxis (WDEIA) in which rash, asthma, or anaphylaxis are provoked during exercise. WDEIA has been attributed to ω-gliadins and glutenins.

Wheat and grains are rich in phytates, compounds that, like wheat germ agglutinin, provide pest-resistance to the plant. Once again, plant geneticists select strains richer in phytates and thereby are more pest-resistant. Phytate content parallels fiber content. This means that conventional advice to consume plentiful fiber from grains, such as whole grain breads and bran cereals hawked for promoting bowel regularity, thereby increases exposure to phytates. Problem: Phytates are effective binders of any mineral that has a positive charge. This includes iron, zinc, magnesium, and calcium. Phytates from grains are therefore a common cause of iron deficiency anemia, unresponsive to iron supplementation (since the iron never makes it to the bloodstream).^{21, 22} Zinc deficiency from phytates results in slowed wound healing, increased susceptibility to infections, skin rashes, impaired taste and smell, and slowed growth in children.²³ Wheat consumption is one of several causes of magnesium deficiency that is ubiquitous and results in bone thinning, higher blood pressure and blood sugar, muscle cramps, and heart rhythm disorders.²⁴ You may begin to appreciate just how many ironies there are in conventional diet advice: Eating more “healthy whole grains” to ensure adequate nutrition actually achieves the opposite.

As if this protein/enzyme smorgasbord weren’t enough, food manufacturers have also turned to fungal enzymes, such as cellulases, glucoamylases, xylanases, and β-xylosidases, to enhance leavening and texture in wheat products. Many bakers also add soy flour to their dough to enhance mixing and whiteness, introducing yet another collection of proteins and enzymes. And farmers add their own unique collection of herbicides and pesticides such as glyphosate, imazamox, malathion, and chlorpyrifos. Choosing organic sources may reduce or eliminate exposure to such chemicals, but you’ve still got to contend with all the components intrinsic to the wheat plant.

In short, wheat is not just a complex carbohydrate with gluten and bran. Wheat is a smorgasbord of compounds that vary widely according to genetic code. Just by looking at a poppy seed muffin, for instance, you would be unable to discern the variety of gliadins, wheat germ agglutinins, and other non-gluten proteins, phytates, and amylopectins contained within, much of it unique to modern semi-dwarf wheat. On taking your first bite, you might enjoy the immediate sweetness of the muffin’s amylopectin A, as it sends your blood sugar skyward, but you may be largely unaware of the toxic effects of its many other components until disaster strikes—in the form of pain and swelling caused by rheumatoid arthritis or stumbling and warm incontinence caused by cerebellar ataxia.

Let’s next explore the incredible wide-ranging health effects of your muffin and other wheat-containing foods.