The Problem with Grain Consumption

If you support the idea that ‘bread is the staff of life’, you may change your mind after examining some facts about how it can affect the human gut, as well as other body systems. Even high-fibre or wholegrains may contain some surprising substances that don’t do the body any good.

The problems with grain consumption started quite a long time ago – thousands of years ago, it seems! Our nomadic hunting-and-gathering Paleolithic forefathers (2 million BCE – 10 000 BCE) didn’t have the easy modern-day access to grains. If and when they did ingest grain, it certainly wasn’t available as sliced white, low GI wholegrain, or lusty lager – nor in the vast quantities gorged and guzzled by humans today!

We have our cultivating-and-storing Neolithic settler kin to thank for freer access to grains, since they’re the lot responsible for the emergence of agriculture, i.e. the agrarian revolution that resulted in more, and steady, per capita food supplies. This evolution-revolution is also responsible for providing more time to develop rules, language and culture (since less time was spent hunting and gathering) – so that’s a plus.

Along with this progress, however, came challenges – the proverbial two-edged sword – since it heralded a significant dietary change that impacted on the evolutionary biology, and ultimately the physiology, of Homo sapiens. Modification of the Paleolithic diet culminated in the current overconsumption of bread, pasta and other such rather delicious starches – because they’re here, there and everywhere. Such progressive ease of access has led to many of the digestive and inflammatory maladies that plague modern man, woman and beast nowadays, since today’s diner no longer has to forage for food – let alone kill, grow, cook or, for that matter, chew it!

In all fairness, as with many things sybaritic, grains cannot really be cast as the primary villains of modern life, for as Hamlet said: ‘there is nothing either good or bad, but thinking makes it so’. Well, this is not quite true when it comes to food sensitivities, but we should rather consider what has led to the problems with grain consumption and attempt to understand and modulate the choices, quantities, and quality of grains eaten as part of our contemporary diets. In many cases it simply boils down to the excesses of our pleasures. The lack of moderation in our nutritional behaviours and choices have created and/or resulted in numerous present-day health problems, because the way we eat grains today is not the way humans have eaten this foodstuff for most of time. The ability to grow and process grains has turned a relatively scarce and luxury item (well, at least for our forebears) into an abundant and cheap source of food today, which we are overeating, usually as part of every meal. Yes, we may be able to afford it, but the million-dollar question is, can our health afford the consequences of this delicious overindulgence?

But before offending every baguette-loving Francophile, vetkoek afficiaonado, and all other categories of bread- and grain-lovers in between, let me try to explain why naturopaths and other health practitioners tend to harp on grains (notwithstanding our other favourite refrain – dairy produce!). Perhaps if we consider what the offending constituents are in grain, per se, it will clarify why these foods are coming under greater nutritional scrutiny. This is relevant for us, since humans (as a species) appear not to be designed to eat grains – at least, not without doing a fair bit of damage to the gut (gastro-intestinal tract/GIT).

Here’s a brief postulation of why grains can cause the grumps:

GRAINS ARE NUTRIENT-DEFICIENT AND CONTAIN ANTINUTRIENTS

Compared to vegetables, fruits, eggs, meat and fish, which are superior sources of nutrients, grains are very poor sources of vitamins and minerals, in particular. Plus, the ‘but they’re fibre-rich’ argument falls a bit flat when we consider that it’s actually the high-fibre bran portion of the grain that contains many of the antinutrients that may be damaging to health. As stated by Professor Loren Cordain from Colorado State University, an expert on Paleolithic lifestyles: ‘Grains are the seeds of a plant. They're its reproductive material, and plants don't make their reproductive material to give away for free to other animals. If they did, they'd become extinct, and so the evolutionary strategy that many plants, particularly cereal grains, have taken to prevent predation is to evolve toxic compounds so that the predator of the seeds can’t eat them, so that they can put their seeds in the soil where they're meant to be, to grow a new plant and not in the gut of an animal to feed it.’

Grains contain phytic acid, a substance known as a mineral-blocker because it inhibits the absorption of important dietary micronutrients like calcium, magnesium, zinc, copper and iron. Phytic acid naturally occurs in the bran portion of all grains, as well as in the skins of nuts and seeds. Although sprouting breaks down phytic acid, sprouting grains is not essentially a good thing, as can be seen later.

GLUTEN, GRAINS INCREASE GUT PERMEABILITY

Unless you think leaky gut syndrome (LGS) sounds like fun, you won’t be a fan of any food that exacerbates this condition. Wheat, rye, barley, etc., yummy as they are, all contain gluten and are generally implicated in LGS, since they mess with the microvilli in the small intestine, which contributes to the leaking of macronutrient particles into the bloodstream. Scientific evidence¹ shows that grains, especially wholegrains (and legumes) are key culprits in increasing gut permeability – irrespective of a person’s coeliac status – because of the antinutrients inherent in them, such as gliadin and leptins.

Leaky gut syndrome (LGS) is a disorder triggered by stress, compounded by food sensitivities or allergies that can cause digestive disturbances like bloating, gas and abdominal pain.

Gliadin, found in wheat gluten, is the substance responsible for giving bread its spongy texture. Besides being considered a primary immunotoxic protein, gliadin can increase the production of another intestinal protein, zonulin. Zonulin, in turn, contributes to, and aggravates, LGS, since it opens up the normally tight gaps that exist between intestinal cells (enterocytes). These gaps allow undigested food particles, allergens and toxins to leak out of the gut and cause havoc in the body, causing various health problems, including systemic inflammation and even organ damage. And even more insidiously, a leaky gut can trick the immune system into attacking itself, a process that is the basis of autoimmune diseases.

Relative to gliadin toxicity, the autoimmune aspect is highlighted in coeliac disease – an autoimmune disease of the small intestine. In coeliac disease, the body makes antibodies to gliadin, after it’s digested by the intestinal enzyme tissue transglutaminase. Once this enzyme modifies the protein, the immune system cross-reacts with small-intestine villi. This results in significant inflammation and autoimmune damage (villous atrophy) to the absorptive surfaces of the intestines. The consequence of this is impairment of nutrient absorption. The scary thing is that gliadin sensitivity is not restricted to coeliac disease. It is hypothesised that the intolerance humans have to gliadin, as well as related wheat proteins, is a species-specific intolerance, i.e. it is applicable to all humans – albeit in varying degrees.

LECTINS

Lectins are not related to the cannibalistic Dr Hannibal Lecter, but can be equally dangerous to some people! These are basically sticky, carbohydrate-binding proteins, which in nature are a key mechanism through which plants protect themselves against being eaten. Though they are found in highest concentrations in their seed form, humans are mostly exposed to them from grains, legumes, nuts, dairy products and nightshade plants (potato, tomato, brinjal and peppers) – but they are found in most plant and animal food sources. NB: All legumes contain lectins, not just beans (especially soy beans, including tofu). They’re also present in peas, lentils and peanuts. However, when it comes to humans and lectin-induced adverse health effects, it seems that the wheat used to make bread (Triticum aestivum) is the worst culprit.

WHEAT GERM AGGLUTININ (WGA)

Now this is a really dodgy customer when it comes to gut dysbiosis. Gut dysbiosis refers to an imbalance in the natural gut flora, which occurs when there is a breakdown in the balance between protective or beneficial intestinal organisms versus harmful intestinal organisms or microbes and other problems. Regarding sensitivities, it is thought that these are predominantly due to today’s wheat being a relatively new form of wheat, which contains the toxic, antinutrient compound, WGA. This is a particularly problematic constituent that is present in high concentration in wholewheat, which can cause the intestines to absorb substances from food that would not normally enter the bloodstream.

Just in case you’re not convinced yet, WGA is responsible for a host of undesirable or health-depleting actions. For example, it is pro-inflammatory,² stimulating the production of cytokines (pro-inflammatory chemical messengers) in both intestinal and immune cells. This is not a good thing, because it can result in chronic gut inflammation.

And if that’s not enough – in human blood, anti-WGA antibodies have been shown to cross-react with other proteins, which may contribute to the development of autoimmune diseases,³ as well as being implicated, apart from the gluten connection, in coeliac disease. It has also been shown to induce thymus atrophy in rat studies. In addition, WGA can cross the blood-brain barrier, and it exhibits certain other neurotoxic actions, e.g. it can attach to the myelin sheath⁴ and inhibit nerve growth factor. This is one of the reasons people with multiple sclerosis (MS) are advised to avoid wheat.

Research also demonstrates that WGA can be cytotoxic⁵ to both normal and cancerous cell lines, and is capable of inducing either cell cycle arrest or apoptosis (programmed cell death). It can also adversely affect GIT function by interfering with the brush border of the intestinal villi, disrupt endocrine function (which may contribute to insulin resistance and weight gain), bind to benign and malignant thyroid nodules, and it has a measure of cardiotoxicity (having a disruptive effect on platelet endothelial cell adhesion). Whew, indeed a tough and potent substance!

And for the ‘sprouters’ out there – while the noxious effects of some substances can be modulated through sprouting (soaking or cooking), WGA is not eliminated through sprouting, so take care.

A NEW FOOD FOR HUMANS

It’s also important to take into consideration that humans have only been consuming unsprouted grains and legumes, like beans, in significant amounts for about 500 generations (unlike certain rodents and birds, who have had thousands of generations to adapt to eating food in this form). Our evolutionary design is simply not on par with these generally lean and lithe creatures. Granted, our every ill cannot be blamed on the increase in grain consumption, but it is interesting to note that in the last 100+ years, chronic disease rates have risen exponentially, while fertility rates have fallen, and simultaneously, weight gain (certainly within Western populations) has risen alarmingly. Coincidence – or could there be a causal link?

So, the question is whether to return to a more Paleolithic diet, rather than the Neolithic-dominant diet of modern times. Who knows for sure? If one can find uncontaminated sources of the types of food our Paleolithic ancestors ate, i.e. primarily a wide variety of vegetables, fruit, roots, nuts, and meat – then maybe. However, these days, such healthy staples have been largely replaced with easy-access junk food and non-organic and often poor quality raw food, due to soil depletion and pollution. For all but the most ardent health food hunter/ gatherer types, the lure of the quick fix is an enticing siren that mercilessly beckons the fast-food junkie, or busy-bee parent. Competing with refined sugar and high fructose corn syrup products, refined breads and cereals, copious carbs like potatoes (including all those ‘slap’ chips and crisps) and white rice, hormone- and antibiotic-laden factory-farmed meat and eggs, pasteurised milk and highly processed food, colourants, flavourants, etc., is a daunting obstacle even for the brave and committed ‘greenies’. It is, however, often too much of a challenge for most mere mortals to want to face – irrespective of the wisdom of genetic ancestry or the desire for a healthier lifestyle.

Maybe you can’t, or don’t want to, make sweeping health changes – but maybe some- thing in the above has sparked your interest enough to perhaps decide to try cutting out grains for a while … even if just to see if you feel better for it, or not. Whatever choice you make, I do hope that the information at least offers some food for thought or an explanation for why so many people have a problem with grain consumption these days.

Alternatively, you may ascribe to the maxim: If it ain’t broke, don’t fix it. If so, and you’re in fine fettle, without any digestive or health grumbles, you’re blessed. If you truly experience no adverse effects from eating grains, have no problems with allergies, insulin sensitivity, or type 2 diabetes, or LGS, and don’t have a problem with obesity, you’ve probably stopped reading this article ages ago and may well consider my opinions daft! Nevertheless, if you’re one of these truly rare canaries, you can simply thank your lucky stars, and know that there’s a horde of people out there who are seriously jealous of your ability to scoff pasta, croissants, breads and pastries without consequence – whether it’s healthy or not. I know I’m one of those simply green with envy!

References

1. Drago S, et al. Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines. Scand J Gastroent 2006;41(4):408-419.
2. Dalla Pellegrina C, et al. Effects of wheat germ agglutinin on human gastrointestinal epithelium: insights from an experimental model of immune/ epithelial cell interaction. Toxicol Appl Pharmacol 2009;237(2):146-153.
3. Tchernychev B, Wilchek M. Natural human antibodies to dietary lectins. FEBS Lett 1996;397(-3):139-142.
4. Dolapchieva S. Distribution of concanavalin A and wheat germ agglutinin binding sites in the rat peripheral nerve fibres revealed by lectin/glycoprotein- gold histochemistry. Histochem J 1996;28(1):7-12.
5. Liu WK, et al. Wheat germ lectin induces G2/M arrest in mouse L929 fibroblasts. J Cell Biochem 2004;91(6):1159-1173.