Wheat Belly Total Health: The effortless grain-free health and weight-loss plan. Dr Davis William
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voluntarily, but rather was obtained by a court order.) When they tried to reproduce the Monsanto data but applied more detailed tissue analyses, they failed to reproduce the same benign findings, instead reporting evidence for kidney, liver, heart, spleen and adrenal toxicity with both forms of GM corn.38 The first effort to extend the period of observation beyond 90 days raised more disturbing questions. Over two years of observation, increased mortality, breast tumours, liver damage and pituitary disruption from both glyphosate-resistant corn and glyphosate itself were reported, in contrast to Monsanto’s benign 90-day findings.39
Further questions have been raised regarding the safety of Bt toxin corn. This strain of corn has a gene for a protein that’s toxic to insects inserted right into it, so it kills pests who try to eat the plant. While Bt toxin-expressing bacteria have been sprayed on crops by organic farmers for 40 years with apparent safety, critics have pointed out that GM corn now expresses Bt toxin within the seed (the corn kernels) directly ingested by consumers. One study in mice demonstrated toxic effects on blood cell formation,40 while another observed prediabetic patterns.41 Genetically modified rice has also been demonstrated to change the composition of bowel flora in mice, with decreased healthy Lactobacillus and increased unhealthy Escherichia coli species.42
Glyphosate itself, the world’s most widely used herbicide, is applied to glyphosate-resistant corn. Various studies suggest it has oestrogenic activity, promoting the growth of breast cancer cells; disrupts male fertility; and disrupts endocrine function in a number of other ways.43 There is also the issue of the environmental impact of glyphosate on wildlife, including aquatic bacteria and amphibians, such as frogs, which experience toxic effects.44
Interestingly, one strain of rice – Golden Rice, which has been genetically modified to express beta-carotene to alleviate the vitamin A deficiency that plagues rice-consuming societies – has been at the forefront of the biotechnology effort to paint genetic modification as something beautiful to behold and safe for consumption. Agribusiness giant Syngenta has been promoting Golden Rice as an example of what the science of genetic modification can accomplish, despite the vigorous opposition of many farmers who wish to avoid using GM grains. Critics have also accused its promoters of trying to capitalize on a common nutrient deficiency by a more profitable route than, say, just having vitamin A-deficient populations eat an occasional sweet potato, which would match or exceed the benefits provided by Golden Rice. (But you can’t trademark a regular, nutritious sweet potato.)
Much of the science purporting to explore the safety of GM crops reads more like marketing than science, with researchers gushing about the safety and nutrition of the crop, herbicide or pesticide in question, rather than impartially reporting the science. This brings us to the fundamental problem when deep-pocketed influences such as agribusiness or the pharmaceutical industry are involved: How much can we believe when much of the positive ‘science’ is generated by those who stand to benefit from it?
Rice
Despite sharing a genetic heritage with other grasses, rice is among the more benign of grains, though it’s far from harmless. Viewed from the perspective of the ancient human experience that reveals the destructive health effects of other grasses, ancient rice is the only grain that was not associated with effects such as increased tooth decay, facial malformations and iron deficiency.45 The less-harmful nature of rice can be partly explained by the very low content (less than 1 per cent) of prolamin proteins in rice.46
The history of rice as yet another seed of grasses consumed by humans dates back 8,000 years to the foothills of the Himalayas, followed by evidence for human cultivation in southern China 4,000 years ago. Rice is the ideal commodity food, as it can be stored for many years without degrading. Health problems from rice, unlike other grains, are less common. Nonetheless, overreliance on rice with the husk removed (i.e., white or polished rice) led to widespread problems with beriberi, a condition that results in partial paralysis and heart failure due to a lack of the B vitamin thiamin – conditions that, I believe you would agree, are beriberi bad. This condition can develop within a few weeks, and it became a problem that plagued Asian sailors and soldiers given rations largely consisting of rice.
As with the seeds of all other grasses, rice shares the potential for excessive glycaemic effects. Carbs account for 85 per cent of the calories in rice, among the highest of all seeds of grasses. Rice-consuming cultures, for instance, can still experience plenty of diabetes. But the comforting notion that rice is among the most benign of grains is being challenged, as it has been the recipient of extensive genetic modification. This includes efforts to make it glyphosate resistant and able to express the Bt toxin, posing the same safety questions as for glyphosate-resistant and Bt toxin-containing corn.
And there’s another issue looming over this particular seed of a grass: rice is unique among grasses in its natural ability to concentrate inorganic arsenic from soil and water. (We can’t blame agribusiness for this effect.) Rice has a high arsenic content, according to reports confirmed by FDA analyses, though the FDA reassures us that no acute toxicity develops from such exposure.47 Substantial research, however, has associated chronic arsenic exposure with multiple forms of cancer, as well as cardiovascular and neurological diseases.48 In Bangladesh, where arsenic exposure is a major public health problem, increasing chronic arsenic exposure, starting at low levels, is associated with premalignant skin lesions, high blood pressure, neurological dysfunction and increased mortality.49 This analysis suggests that adverse health effects can manifest with chronic exposure provided by as little as one serving (approximately 185 g (6½ oz) cooked) of rice per day. The FDA had previously established an upper limit for arsenic in apple juice of 10 parts per billion; analyses of rice have found many rice products approaching or exceeding this cutoff.
The data that already exist linking low-level exposure of arsenic-contaminated water with increases in many chronic diseases is, in my mind, all the information we need. Makes you shudder to think about the old Rice Diet. Although at the more benign end of the spectrum as far as seeds of grasses go, enthusiastic consumption of rice in any form (white, brown or wild) is clearly not a good idea for health. Occasional consumption of small quantities (around 50 g (2 oz)) is probably all a healthy human can tolerate before triggering such concerns.
Oats
Oats are relative newcomers to the human dietary grass experience, having been first consumed only about 3,000 years ago. Few cultures embraced this grain, often regarding it as fodder for livestock or the food of barbarians, until the Welsh and Scots became avid oat consumers. Yet another close relative of wheat and member of the grass family, its gliadin-like protein, avenin, shares less overlap in its structure than its counterparts in rye and barley do. For this reason, the role of oats in the diet of people with coeliac disease has been debated for 50 years. The avenin protein is clearly more benign, though some oat varieties can mimic the immune effects of gliadin.50 (The notion of ‘gluten-free oats’ is therefore a fiction, as they still have a protein that can overlap in structure and effect.) Oats lack a lectin protein, so they do not contribute to the intestinal damage and inflammation inflicted by wheat germ agglutinin.51 This focus on the relatively benign nature of oats in comparison with the worst grain of all, though, falsely lulls people into thinking that just because it doesn’t have gluten-like properties, it must be good for you. Once again, overly simplistic nutritional thinking can get us into trouble.
There is plenty of talk about oats being ‘heart healthy’ and a rich source of soluble fibre, referring to the beta-glucan in oats that has been shown to reduce total and LDL cholesterol. All of that is true – except for the heart-healthy part. Although the beta-glucan fibre does indeed have some healthy effects on cholesterol values, the plentiful amylopectin starch of oats raises blood sugar to high levels and therefore provokes extravagant glycation – the irreversible process of modifying proteins when blood glucose rises. Oats provide an example of something that contains a mixture of good things and bad. The good effects are transient, such as the beta-glucan allowing healthier bowel movements and lower LDL cholesterol, or the B vitamins providing nutrition. But the bad effects are irreversible, especially those of glycation. Consumption of oats, like rice, is best kept to a minimum.
Sorghum