Читать книгу Wheat Belly - William MD Davis - Страница 10
ОглавлениеNOT YOUR GRAN’S MUFFINS: THE CREATION OF MODERN WHEAT
He is as good as good bread.
Miguel de Cervantes,
Don Quixote
WHEAT, MORE THAN any other foodstuff (including sugar, fat and salt), is woven into the fabric of the Western food experience, a trend that began even before 1950s US TV show Ozzie met Harriet. It has become such a ubiquitous part of our diet in so many ways that it seems essential to our lifestyle. What would a fry-up be without toast, lunch without sarnies, bacon butty without bread, picnics without hot-dog buns, dip without crackers, hummus without pitta, coffee without a croissant, apple pie without the pastry?
IF IT’S TUESDAY, IT MUST BE WHEAT
I once measured the length of the bread aisle at my local supermarket: sixty-eight feet.
That’s sixty-eight feet of white bread, whole-wheat bread, multi-grain bread, seven-grain bread, rye bread, pumpernickel bread, sourdough bread, Italian bread, French bread, bread sticks, white bagels, raisin bagels, cheese bagels, garlic bagels, oat bread, flax bread, pitta bread, dinner rolls, Kaiser rolls, poppy seed rolls, hamburger buns, and fourteen varieties of hot dog buns. That’s not even counting the bakery and the additional forty feet of shelves packed with a variety of ‘artisanal’ wheat products.
And then there’s the snack aisle with forty-something brands of crackers and twenty-seven brands of pretzels. The baking aisle has bread crumbs and croutons. The dairy case has dozens of those tubes you crack open to bake rolls, Danish pastries and croissants.
Breakfast cereals fill a world unto themselves, usually enjoying a monopoly over an entire supermarket aisle, top to bottom shelf.
There’s much of an aisle devoted to boxes and bags of pasta and noodles: spaghetti, lasagna, penne, elbows, shells, whole-wheat pasta, green spinach pasta, orange tomato pasta, egg noodles, tiny-grained couscous to seven-inch-wide lasagne sheets.
How about frozen foods? The freezer has hundreds of noodle, pasta and wheat-containing side dishes to accompany the meat loaf and roast beef au jus.
In fact, apart from the detergent and soap aisle, there’s barely a shelf that doesn’t contain wheat products. Can you blame Americans if they’ve allowed wheat to dominate their diets? After all, it’s in practically everything.
Wheat as a crop has succeeded on an unprecedented scale, exceeded only by corn in acreage of farmland planted. It is, by a long stretch, among the most consumed grains on earth, constituting 20 per cent of all calories consumed.
And wheat has been an undeniable financial success. How many other ways can a manufacturer transform five pence worth of raw material into £2.50 worth of glitzy, consumer-friendly product, topped off with endorsements from the American Heart Association? In most cases, the cost of marketing these products exceeds the cost of the ingredients themselves.
Foods made partly or entirely of wheat for breakfast, lunch, dinner and snacks have become the rule. Indeed, such a regimen would make the USDA, the Whole Grains Council, the Whole wheat Council, the American Dietetic Association, the American Diabetes Association and the American Heart Association happy, knowing that their message to eat more ‘healthy whole grains’ has gained a wide and eager following.
So why has this seemingly benign plant that sustained generations of humans suddenly turned on us? For one thing, it is not the same grain our forebears ground into their daily bread. Wheat naturally evolved to only a modest degree over the centuries, but it has changed dramatically in the past fifty years under the influence of agricultural scientists. Wheat strains have been hybridised, crossbred and introgressed to make the wheat plant resistant to environmental conditions, such as drought, or pathogens, such as fungi. But most of all, genetic changes have been induced to increase yield per acre. The average yield on a modern North American farm is more than tenfold greater than farms of a century ago. Such enormous strides in yield have required drastic changes in genetic code, including reducing the proud ‘amber waves of grain’ of yesteryear to the rigid, eighteen-inch-tall high-production ‘dwarf’ wheat of today. Such fundamental genetic changes, as you will see, have come at a price.
Even in the few decades since our American grandmothers survived Prohibition and danced the Big Apple, wheat has undergone countless transformations. As the science of genetics has progressed over the past fifty years, permitting human intervention at a much more rapid rate than nature’s slow, year-by-year breeding influence, the pace of change has increased exponentially. The genetic backbone of your high-tech poppy-seed muffin has achieved its current condition by a process of evolutionary acceleration that makes us look like Homo habilis trapped somewhere in the early Pleistocene.
FROM NATUFIAN PORRIDGE TO DOUGHNUT HOLES
‘Give us this day our daily bread.’
It’s in the Bible. In Deuteronomy, Moses describes the Promised Land as ‘a land of wheat and barley and vineyards’. Bread is central to religious ritual. Jews celebrate Passover with unleavened matzo to commemorate the flight of the Israelites from Egypt. Christians consume wafers representing the body of Christ. Muslims regard unleavened naan as sacred, insisting it be stored upright and never thrown away in public. In the Bible, bread is a metaphor for bountiful harvest, a time of plenty, freedom from starvation, even a source of salvation.
Don’t we break bread with friends and family? Isn’t something new and wonderful ‘the best thing since sliced bread’? ‘Taking the bread out of someone’s mouth’ is to deprive that person of a fundamental necessity. Bread is a nearly universal diet staple: chapati in India, tsoureki in Greece, pitta in the Middle East, aebleskiver in Denmark, naan bya for breakfast in Burma, glazed doughnuts any old time in the United States.
The notion that a foodstuff so fundamental, so deeply ingrained in the human experience, can be bad for us is, well, unsettling and counter to long-held cultural views of wheat and bread. But today’s bread bears little resemblance to the loaves that emerged from our forebears’ ovens. Just as a modern Napa Cabernet Sauvignon is a far cry from the crude ferment of fourth-century BC Georgian winemakers who buried wine urns in underground mounds, so has wheat changed. Bread and other foods made of wheat have sustained humans for centuries, but the wheat of our ancestors is not the same as modern commercial wheat that reaches your breakfast, lunch and dinner table. From the original strains of wild grass harvested by early humans, wheat has exploded to more than 25,000 varieties, virtually all of them the result of human intervention.
In the waning days of the Pleistocene, around 8500 BC, millennia before any Christian, Jew or Muslim walked the earth, before the Egyptian, Greek and Roman empires, the Natufians led a semi-nomadic life roaming the Fertile Crescent (now Syria, Jordan, Lebanon, Israel and Iraq), supplementing their hunting and gathering by harvesting indigenous plants. They harvested the ancestor of modern wheat, einkorn, from fields that flourished wildly in open plains. Meals of gazelle, boar, fowl and ibex were rounded out with dishes of wild-growing grain and fruit. Relics like those excavated at the Tell Abu Hureyra settlement in what is now central Syria suggest skilled use of tools such as sickles and mortars to harvest and grind grains, as well as storage pits for stockpiling harvested food. Remains of harvested wheat have been found at archaeological digs in Tell Aswad, Jericho, Nahal Hemar, Navali Cori and other locales. Wheat was ground by hand, then eaten as porridge. The modern concept of bread leavened by yeast would not come along for several thousand years.
Natufians harvested wild einkorn wheat and may have purposefully stored seeds to sow in areas of their own choosing the next season. Einkorn wheat eventually became an essential component of the Natufian diet, reducing the need for hunting and gathering. The shift from harvesting wild grain to cultivating it was a fundamental change that shaped their subsequent migratory behaviour, as well as the development of tools, language and culture. It marked the beginning of agriculture, a lifestyle that required long-term commitment to more or less permanent settlement, a turning point in the course of human civilisation. Growing grains and other foods yielded a surplus of food that allowed for occupational specialisation, government and all the elaborate trappings of culture (while, in contrast, the absence of agriculture arrested cultural development at something resembling Neolithic life).
Over most of the ten thousand years that wheat has occupied a prominent place in the caves, huts and adobes and on the tables of humans, what started out as harvested einkorn, then emmer, followed by cultivated Triticum aestivum, changed gradually and only in small fits and starts. The wheat of the seventeenth century was the wheat of the eighteenth century, which in turn was much the same as the wheat of the nineteenth century and the first half of the twentieth century. Riding your oxcart through the countryside during any of these centuries, you’d see fields of four-foot tall ‘amber waves of grain’ swaying in the breeze. Crude human wheat breeding efforts yielded hit-and-miss, year-over-year incremental modifications, some successful, most not, and even a discerning eye would be hard pressed to tell the difference between the wheat of early twentieth-century farming from its many centuries of predecessors.
During the nineteenth and early twentieth centuries, as in many preceding centuries, wheat changed little. The Pillsbury’s Best XXXX flour my grandmother used to make her famous sour cream muffins in 1940 was little different from the flour of her great-grandmother sixty years earlier or, for that matter, from that of a relative two centuries before that. Grinding of wheat had become more mechanised in the twentieth century, yielding finer flour on a larger scale, but the basic composition of the flour remained much the same.
That all ended in the latter part of the twentieth century, when an upheaval in hybridisation methods transformed this grain. What now passes for wheat has changed, not through the forces of drought or disease or a Darwinian scramble for survival, but through human intervention. As a result, wheat has undergone a more drastic transformation than Joan Rivers, stretched, sewed, cut, and stitched back together to yield something entirely unique, nearly unrecognisable when compared to the original and yet still called by the same name: wheat.
Modern commercial wheat production has been intent on delivering features such as increased yield, decreased production costs and large-scale production of a consistent commodity. All the while, virtually no questions have been asked about whether these features are compatible with human health. I submit that, somewhere along the way during wheat’s history, perhaps five thousand years ago but more likely fifty years ago, wheat changed.
The result: a loaf of bread, biscuit, or pancake of today is different than its counterpart of a thousand years ago, different even from what our grandmothers made. They might look the same, even taste much the same, but there are biochemical differences. Small changes in wheat protein structure can spell the difference between a devastating immune response to wheat protein versus no immune response at all.
WHEAT BEFORE GENETICISTS GOT HOLD OF IT
Wheat is uniquely adaptable to environmental conditions, growing in Jericho, 850 feet below sea level, to Himalayan mountainous regions 10,000 feet above sea level. Its latitudinal range is also wide, ranging from as far north as Norway, 65° north latitude, to Argentina, 45° south latitude. Wheat occupies sixty million acres of farmland in the United States, an area equal to the state of Ohio. Worldwide, wheat is grown on an area ten times that figure, or twice the total acreage of Western Europe.
The first wild, then cultivated, wheat was einkorn, the great-granddaddy of all subsequent wheat. Einkorn has the simplest genetic code of all wheat, containing only fourteen chromosomes. Circa 3300 BC, hardy, cold-tolerant einkorn wheat was a popular grain in Europe. This was the age of the Tyrolean Iceman, fondly known as Ötzi. Examination of the intestinal contents of this naturally mummified Late Neolithic hunter, killed by attackers and left to freeze in the mountain glaciers of the Austrian/Italian Alps, revealed the partially digested remains of einkorn wheat consumed as unleavened flatbread, along with remains of plants, deer and ibex meat.1
Shortly after the cultivation of the first einkorn plant, the emmer variety of wheat, the natural offspring of parents einkorn and an unrelated wild grass, Aegilops speltoides or goatgrass, made its appearance in the Middle East.2 Goatgrass added its genetic code to that of einkorn, resulting in the more complex twenty-eight-chromosome emmer wheat. Plants such as wheat have the ability to retain the sum of the genes of their forebears. Imagine that, when your parents mated to create you, rather than mixing chromosomes and coming up with forty-six chromosomes to create their offspring, they combined forty-six chromosomes from Mum with forty-six chromosomes from Dad, totalling ninety-two chromosomes in you. This, of course, doesn’t happen in higher species. Such additive accumulation of chromosomes in plants is called polyploidy.
Einkorn and its evolutionary successor emmer wheat remained popular for several thousand years, sufficient to earn their place as food staples and religious icons, despite their relatively poor yield and less desirable baking characteristics compared to modern wheat. (These denser, cruder flours would have yielded lousy ciabattas or bear claws.) Emmer wheat is probably what Moses referred to in his pronouncements, as well as the kussemeth mentioned in the Bible, and the variety that persisted up until the dawn of the Roman Empire.
Sumerians, credited with developing the first written language, left us tens of thousands of cuneiform tablets. Pictographic characters scrawled on several tablets, dated to 3000 BC, describe recipes for breads and pastries, all made by taking pestle and mortar or a hand-pushed grinding wheel to emmer wheat. Sand was often added to the mixture to hasten the laborious grinding process, leaving bread-eating Sumerians with sand-chipped teeth.
Emmer wheat flourished in ancient Egypt, its cycle of growth suited to the seasonal rise and fall of the Nile. Egyptians are credited with learning how to make bread ‘rise’ by the addition of yeast. When the Jews fled Egypt, in their hurry they failed to take the leavening mixture with them, forcing them to consume unleavened bread made from emmer wheat.
Sometime in the millennia predating biblical times, twenty-eight-chromosome emmer wheat (Triticum turgidum) mated naturally with another grass, Triticum tauschii, yielding primordial forty-two-chromosome Triticum aestivum, genetically closest to what we now call wheat. Because it contains the sum total of the chromosomal content of three unique plants with forty-two chromosomes, it is the most genetically complex. It is therefore the most genetically ‘pliable’, an issue that will serve future genetics researchers well in the millennia to come.
Over time, the higher yielding and more baking-compatible Triticum aestivum species gradually overshadowed its parents einkorn and emmer wheat. For many ensuing centuries, Triticum aestivum wheat changed little. By the mid-eighteenth century, the great Swedish botanist and biological cataloguer, Carolus Linnaeus, father of the Linnean system of the categorisation of species, counted five different varieties falling under the Triticum genus.
Wheat did not evolve naturally in the New World, but was introduced by Christopher Columbus, whose crew first planted a few grains in Puerto Rico in 1493. Spanish explorers accidentally took wheat seeds in a sack of rice to Mexico in 1530, and later introduced it to the American southwest. The namer of Cape Cod and discoverer of Martha’s Vineyard, Bartholomew Gosnold, first took wheat to New England in 1602, followed shortly thereafter by the Pilgrims, who transported wheat with them on the Mayflower.
The Real Wheat
What was the wheat grown ten thousand years ago and harvested by hand from wild fields like? That simple question took me to the Middle East – or more precisely, to a small organic farm in western Massachusetts.
There I found Elisheva Rogosa. Eli is not only a science teacher but an organic farmer, advocate of sustainable agriculture and founder of the Heritage Wheat Conservancy (www.growseed.org), an organisation devoted to preserving ancient food crops and cultivating them using organic principles. After living in the Middle East for ten years and working with the Jordanian, Israeli and Palestinian GenBank project to collect nearly extinct ancient wheat strains, Eli returned to the United States with seeds descended from the original wheat plants of ancient Egypt and Canaan. She has since devoted herself to cultivating the ancient grains that sustained her ancestors.
My first contact with Ms Rogosa began with an exchange of emails that resulted from my request for two pounds (900 grams) of einkorn wheat grain. She couldn’t stop herself from educating me about her unique crop, which was not just any old wheat grain, after all. Eli described the taste of einkorn bread as ‘rich, subtle, with more complex flavour,’ unlike bread made from modern wheat flour, which she claimed tasted like cardboard.
Eli bristles at the suggestion that wheat products might be unhealthy, citing instead the yield-increasing, profit-expanding agricultural practices of the past few decades as the source of adverse health effects of wheat. She views einkorn and emmer as the solution, restoring the original grasses, grown under organic conditions, to replace modern industrial wheat.
And so it went, a gradual expansion of the reach of wheat plants with only modest and gradual evolutionary selection at work.
Today einkorn, emmer, and the original wild and cultivated strains of Triticum aestivum have been replaced by thousands of modern human-bred offspring of Triticum aestivum, as well as Triticum durum (pasta) and Triticum compactum (very fine flours used to make cupcakes and other products). To find einkorn or emmer today, you’d have to look for the limited wild collections or modest human plantings scattered around the Middle East, southern France, and northern Italy. Courtesy of modern human-designed hybridisations, Triticum species of today are hundreds, perhaps thousands, of genes apart from the original einkorn wheat that bred naturally.
Triticum wheat of today is the product of breeding to generate greater yield and characteristics such as disease, drought and heat resistance. In fact, wheat has been modified by humans to such a degree that modern strains are unable to survive in the wild without human support such as nitrate fertilisation and pest control.3 (Imagine this bizarre situation in the world of domesticated animals: an animal able to exist only with human assistance, such as special feed, or else it would die.)
Differences between the wheat of the Natufians and what we call wheat in the twenty-first century would be evident to the naked eye. Original einkorn and emmer wheat were ‘hulled’ forms, in which the seeds clung tightly to the stem. Modern wheats are ‘naked’ forms, in which the seeds depart from the stem more readily, a characteristic that makes threshing (separating the edible grain from the inedible chaff) easier and more efficient, determined by mutations at the Q and Tg (tenacious glume) genes.4 But other differences are even more obvious. Modern wheat is much shorter. The romantic notion of tall fields of wheat grain gracefully waving in the wind has been replaced by ‘dwarf’ and ‘semi-dwarf’ varieties that stand barely a foot or two tall, yet another product of breeding experiments to increase yield.
SMALL IS THE NEW BIG
For as long as humans have practised agriculture, farmers have strived to increase yield. Marrying a woman with a dowry of several acres of farmland was, for many centuries, the primary means of increasing crop yield, arrangements often accompanied by several goats and a sack of rice. The twentieth century introduced mechanised farm machinery, which replaced animal power and increased efficiency and yield with less manpower, providing another incremental increase in yield per acre. While production in the United States was usually sufficient to meet demand (with distribution limited more by poverty than by supply), many other nations worldwide were unable to feed their populations, resulting in widespread hunger.
In modern times, humans have tried to increase yield by creating new strains, crossbreeding different wheats and grasses and generating new genetic varieties in the laboratory. Hybridisation efforts involve techniques such as introgression and ‘back-crossing’, in which offspring of plant breeding are mated with their parents or with different strains of wheat or even other grasses. Such efforts, though first formally described by Austrian priest and botanist Gregor Mendel in 1866, did not begin in earnest until the mid-twentieth century, when concepts such as heterozygosity and gene dominance were better understood. Since Mendel’s early efforts, geneticists have developed elaborate techniques to obtain a desired trait, though much trial and error is still required.
Much of the current world supply of purposefully bred wheat is descended from strains developed at the International Maize and Wheat Improvement Center (IMWIC), located east of Mexico City at the foot of the Sierra Madre Oriental mountains. IMWIC began as an agricultural research programme in 1943 through a collaboration of the Rockefeller Foundation and the Mexican government to help Mexico achieve agricultural self-sufficiency. It grew into an impressive worldwide effort to increase the yield of corn, soya and wheat, with the admirable goal of reducing world hunger. Mexico provided an efficient proving ground for plant hybridisation, since the climate allows two growing seasons per year, cutting the time required to hybridise strains by half. By 1980, these efforts had produced thousands of new strains of wheat, the most high-yielding of which have since been adopted worldwide, from Third World countries to modern industrialised nations, including the United States.
One of the practical difficulties solved during IMWIC’s push to increase yield is that, when large quantities of nitrogen-rich fertiliser are applied to wheat fields, the seed head at the top of the plant grows to enormous proportions. The top-heavy seed head, however, buckles the stalk (what agricultural scientists call ‘lodging’). Buckling kills the plant and makes harvesting problematic. University of Minnesota-trained geneticist Norman Borlaug, working at IMWIC, is credited with developing the exceptionally high-yielding dwarf wheat that was shorter and stockier, allowing the plant to maintain erect posture and resist buckling under the large seed head. Tall stalks are also inefficient; short stalks reach maturity more quickly, which means a shorter growing season with less fertiliser required to generate the otherwise useless stalk.
Dr Borlaug’s wheat-hybridising accomplishments earned him the title of ‘Father of the Green Revolution’ in the agricultural community, as well as the Presidential Medal of Freedom, the Congressional Gold Medal, and the Nobel Peace Prize in 1970. On his death in 2009, the Wall Street Journal eulogised him: ‘More than any other single person, Borlaug showed that nature is no match for human ingenuity in setting the real limits to growth.’ Dr Borlaug lived to see his dream come true: his high-yield dwarf wheat did indeed help solve world hunger, with the wheat crop yield in China, for example, increasing eightfold from 1961 to 1999.
Dwarf wheat today has essentially replaced most other strains of wheat in the United States and much of the world thanks to its extraordinary capacity for high yield. According to Allan Fritz, PhD, professor of wheat breeding at Kansas State University, dwarf and semi-dwarf wheat now comprise more than 99 per cent of all wheat grown worldwide.
BAD BREEDING
The peculiar oversight in the flurry of breeding activity, such as that conducted at IMWIC, was that, despite dramatic changes in the genetic make-up of wheat and other crops, no animal or human safety testing was conducted on the new genetic strains that were created. So intent were the efforts to increase yield, so confident were plant geneticists that hybridisation yielded safe products for human consumption, so urgent was the cause of world hunger, that these products of agricultural research were released into the food supply without human safety concerns being part of the equation.
It was simply assumed that, because hybridisation and breeding efforts yielded plants that remained essentially ‘wheat’, new strains would be perfectly well tolerated by the consuming public. Agricultural scientists, in fact, scoff at the idea that hybridisation has the potential to generate hybrids that are unhealthy for humans. After all, hybridisation techniques have been used, albeit in cruder form, in crops, animals, even humans for centuries. Mate two varieties of tomatoes, you still get tomatoes, right? What’s the problem? The question of animal or human safety testing is never raised. With wheat, it was likewise assumed that variations in gluten content and structure, modifications of other enzymes and proteins, qualities that confer susceptibility or resistance to various plant diseases, would all make their way to humans without consequence.
Judging by research findings of agricultural geneticists, such assumptions may be unfounded and just plain wrong. Analyses of proteins expressed by a wheat hybrid compared to its two parent strains have demonstrated that, while approximately 95 per cent of the proteins expressed in the offspring are the same, 5 per cent are unique, found in neither parent.5 Wheat gluten proteins, in particular, undergo considerable structural change with hybridisation. In one hybridisation experiment, fourteen new gluten proteins were identified in the offspring that were not present in either parent wheat plant.6 Moreover, when compared to century-old strains of wheat, modern strains of Triticum aestivum express a higher quantity of genes for gluten proteins that are associated with coeliac disease.7
A Good Grain Gone Bad?
Given the genetic distance that has evolved between modern-day wheat and its evolutionary predecessors, is it possible that ancient grains such as emmer and einkorn can be eaten without the unwanted effects that attach to other wheat products?
I decided to put einkorn to the test, grinding 900 grams of whole grain to flour, which I then used to make bread. I also ground conventional organic whole-wheat flour from seed. I made bread from both the einkorn and conventional flour using only water and yeast with no added sugars or flavourings. The einkorn flour looked much like conventional whole-wheat flour, but once water and yeast were added, differences became evident: the light brown dough was less stretchy, less pliable and stickier than a traditional dough, and lacked the mouldability of conventional wheat flour dough. The dough smelt different, too, more like peanut butter rather than the standard neutral smell of dough. It rose less than modern dough, rising just a little, compared to the doubling in size expected of modern bread. And, as Eli Rogosa claimed, the final bread product did indeed taste different: heavier, nutty, with an astringent aftertaste. I could envision this loaf of crude einkorn bread on the tables of third-century BC Amorites or Mesopotamians.
I have a wheat sensitivity. So, in the interest of science, I conducted my own little experiment: 115 grams of einkorn bread on day one versus 115 grams of modern organic whole-wheat bread on day two. I braced myself for the worst, since in the past my reactions have been rather unpleasant.
Beyond simply observing my physical reaction, I also performed fingerstick blood sugars after eating each type of bread. The differences were striking.
Blood sugar at the start: 84 mg/dl. Blood sugar after consuming einkorn bread: 110 mg/dl. This was more or less the expected response to eating some carbohydrate. Afterwards, though, I felt no perceptible effects – no sleepiness, no nausea, nothing hurt. In short, I felt fine. Whew!
The next day, I repeated the procedure, substituting 115 grams of conventional organic whole-wheat bread. Blood sugar at the start: 84 mg/dl. Blood sugar after consuming conventional bread: 167 mg/dl. Moreover, I soon became nauseated, nearly losing my lunch. The queasy effect persisted for thirty-six hours, accompanied by stomach cramps that started almost immediately and lasted for many hours. Sleep that night was fitful, though filled with vivid dreams. I couldn’t think straight, nor could I understand the research papers I was trying to read the next morning, having to read and reread paragraphs four or five times; I finally gave up. Only a full day and a half later did I start feeling normal again.
I survived my little wheat experiment, but I was impressed with the difference in responses to the ancient wheat and the modern wheat in my whole-wheat bread. Surely something odd was going on here.
My personal experience, of course, does not qualify as a clinical trial. But it raises some questions about the potential differences that span a distance of ten thousand years: ancient wheat that predates the changes introduced by human genetic intervention versus modern wheat.
Multiply these alterations by the tens of thousands of hybridisations to which wheat has been subjected and you have the potential for dramatic shifts in genetically determined traits such as gluten structure. And note that the genetic modifications created by hybridisation for the wheat plants themselves were essentially fatal, since the thousands of new wheat breeds were helpless when left to grow in the wild, relying on human assistance for survival.8
The new agriculture of increased wheat yield was initially met with scepticism in the Third World, with objections based mostly on the perennial ‘That’s not how we used to do it’ variety. Dr Borlaug, hero of wheat hybridisation, answered critics of high-yield wheat by blaming explosive world population growth, making high-tech agriculture a ‘necessity’. The marvellously increased yields enjoyed in hunger-plagued India, Pakistan, China, Colombia and other countries quickly quieted naysayers. Yields improved exponentially, turning shortages into surplus and making wheat products cheap and accessible.
Can you blame farmers for preferring high-yield dwarf hybrid strains? After all, many small farmers struggle financially. If they can increase yield-per-acre up to tenfold, with a shorter growing season and easier harvest, why wouldn’t they?
In the future, the science of genetic modification has the potential to change wheat even further. No longer do scientists need to breed strains, cross their fingers and hope for just the right mix of chromosomal exchange. 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 fertilisers or pesticides. This is a financially rewarding process for big agribusiness, and seed and farm chemical producers such as Cargill, Monsanto and ADM, since specific strains of seed can be patent protected and thereby command a premium and boost sales of the compatible chemical treatments.
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 than the assumed-to-be-benign practice of hybridisation. 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 soya beans (known as Roundup Ready, these beans are genetically bred to allow the farmer to freely spray the weed killer Roundup without harming the crop) show alterations in liver, pancreatic, intestinal and testicular tissue compared to animals fed conventional soya beans. 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.9
It took the introduction of gene modification to finally bring the notion of safety testing for genetically altered plants to light. Public outcry has 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 help determine what new genetically modified crops should be subjected to safety testing, what kinds of tests should be conducted and what should be measured.
But no such outcry was raised years earlier as farmers and geneticists carried out tens of thousands of hybridisation 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 effects. Hybridisation efforts continue, breeding new ‘synthetic’ wheat. While hybridisation falls short of the precision of gene modification techniques, it still possesses 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.10
Thus, the alterations of wheat that could potentially result in undesirable effects on humans are not due to gene insertion or deletion, but are due to the hybridisation experiments that predate genetic modification. As a result, over the past fifty years, thousands of new strains have made it to the human commercial food supply 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 hundreds, if not 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 hybridisation 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. Nor is it known whether only some or all of the hybrid wheat generated has potential for undesirable human health effects.
The incremental genetic variations introduced with each round of hybridisation 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 dalliances. 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 hybridisations make for substantial variation in composition, appearance and qualities important not just to chefs and food processors, but also potentially to human health.
