(Image: © Edward Rozzo/Corbis)
The defining difference between our native hunter-gatherer diet and the way we eat now rests upon our relatively recent decision as a species to subsist on cereal grains, most of which are derived from the Poaceae, or grass family. Instead of moving from place to place, following the migration of different animals, or to different climates in different seasons, agriculture allowed humans to settle in one place and grow most if not all of their food. Although our hunter-gatherer ancestors ate some types of wild grass, it was only ever a minor food and was never cultivated on the mass scale required to sustain a sedentary population.
As a species we have only been consuming cereal grains for the last 9000 years, which is a tiny fraction of time if we consider our two million year evolution as hunter-gatherers. Developing some time after the domestication of animals, agriculture slowly spread all over the world during the last several millennia, only reaching some places in the last few hundred years. Given the new technology and culture that evolved during this time, anthropologists were apt to conclude that civilization is a product of agriculture and sedentary living. Recent findings of a hunter-gatherer civilization at Göbekli Tepe in Turkey however seems to contradict this notion, turning our understanding of cultural evolution upside-down. It may be that agriculture is not a civilizing imperative after all.
In fact, there is a significant amount of evidence that an agrarian lifestyle, and hence agrarian diet, is far from optimal, and may fundamentally underlie much of the ‘modern’ disease we experience, including infection, anemia, diseases of the bones and teeth and other degenerative conditions (Cordain 1999). Diabetes mellitus for example is a disease that is clearly related to the agrarian diet and its reliance upon carbohydrate-rich cereals. Diabetes is first mentioned by the Eber’s Papyrus of ancient Egypt, a civilization that was wholly dependent on agriculture. Mention of diabetes is also found in Ayurveda as madhumeha, or ‘honey urine’, once again, showing up in a culture for which carbohydrates were a staple. In the West, diabetes prevalence has increased dramatically since the Roman physician Galen noted it in the 2nd century CE, to become a relatively common disease of 18th century Europe. The most dramatic evidence of the impact of the agrarian imperative however is found among the indigenous peoples of the New World. In less than 150 years since being forced to abandon their hunter-gatherer diet, the prevalence of diabetes among First Nations in Canada is epidemic, about 3-5 times the national average (Young et al 2000). Today more than a decade of research on metabolic syndrome suggests that a reliance on dietary carbohydrates is not only an important cause of diabetes, but many of the diseases that plague modern society including obesity, heart disease and cancer.
By virtue of their carbohydrate or ‘sugar’ content, all cereal grains and especially those refined as a flour promote an increase in blood sugar that enhances insulin secretion and results in hypoglycemia. This effect is mediated in part by the fiber content of the carbohydrate, i.e. the more fiber in the cereal grain, the more slowly it turns into a simple sugar. Apart from slowing down carbohydrate digestion, fiber has also been shown to have a number of benefits, particularly in promoting bowel regularity and supporting the gut ecology. This benefit however comes at the expense of nutrient assimilation. Most cereal grains contain a chemical called phytic acid that binds to certain minerals such as calcium and iron thereby minimizing their absorption and promoting nutrient deficiencies. Also found in cereal grains and legumes are a class of compounds called lectins that can cause inflammatory changes in the gut as well as induce autoimmune reactions. Traditional measures such as sprouting, toasting the cereal, natural fermentation (e.g. sourdough), soaking the grain in an acid medium such as lime juice, or in an alkaline medium such as mineral lime, can all be helpful to partially destroy and denature these anti-nutrient compounds.
Regardless of the traditional methods of preparation some grains including wheat, spelt, kamut, rye, barley and oat all contain a protein called gluten that is resistant to processing. Gluten gives these cereals a glue-like consistency that allows the dough to rise, trapping air bubbles released by the added yeast or sourdough culture. It can isolated from wheat by soaking and washing a dough made from regular white flour, leaching off the starches. Beyond its utility in leavened breads, the sticky properties of gluten are used to good measure in other applications such as paper-making, wallpaper paste, paper-mâché and play-dough. Etymologically the word ‘gluten’ is derived from the word ‘glutinis’ in Latin, meaning ‘glue’. And no matter what the other kids told you at the arts and craft table in Kindergarten, you shouldn’t be eating the glue.
Given the sticky, glue-like property of gluten and flour, it is easy to appreciate that gluten is very difficult to digest. At the extreme end are celiacs that totally lack the enzymes necessary to digest gluten protein. Although less than 1% of the population are diagnosed with celiac disease, researchers suspect that gluten intolerance may be much more common than previously thought. Wheat is the second most common food allergy after cow’s milk, and can manifest in rather obvious ways such as irritable bowel syndrome or in a more discrete fashion. In my practice I have consistently noted that gluten consumption can worsen pre-existing allergies to animal dander and hayfever. Research also indicates that the regular consumption of gluten can promote neurological damage, without necessarily causing any digestive symptoms. Once a patient has been counseled and gets the proper support to eat gluten-free, they often notice that emotional issues such as anxiety and depression begin to improve, further supporting the gut-brain theory of gluten intolerance.
When a gluten sensitivity or allergy is suspected, it is important to eliminate any kind of gluten-containing product including breads, pasta, pastries, muffins and breakfast cereal. Gluten is also used by the food industry as a kind of ‘food ‘glue’ in processed foods. Common culprits include prepared meats, processed cheeses, condiments, sweeteners and candy. The best way to go gluten-free is to eat fresh whole foods with minimal processing.
While I tend to recommend to my patients that they avoid sources of gluten, some cereal grains seem to be well-tolerated. These include cereals from other plant families besides the grasses such as quinoa, as well as non-gluten grasses such as rice. Recognizing the problem with gluten, many people choose to eat and prepare non-gluten food nowadays, seeking out substitutes to make the new look familiar. Unfortunately, making gluten-free favorites such as pancakes or bread still requires some kind of flour, and regardless of the grain, any flour is sticky, heavy and hard to digest. I encourage my patients to eat these non-gluten grains but instead prepared as a pilaf or cooked in soups and stews to ensure good digestion. Using traditional methods of processing, the best tolerated cereal grains include quinoa, rice, amaranth, buckwheat, millet, teff, sorghum and finger-millet. Prepared in a soup, stew, porridge or pilaf, I also find that some gluten-containing grains are well-tolerated including barley and oats. This suggests that the problem of gluten intolerance may be in part due to the mechanical effects of flour in the gut, increasing the sensitivity of the intestinal wall to proteins such as gluten. My general rule of thumb is that if you can get your food to stick to the wall or ceiling, like pasta for example, then you probably want to avoid it. Basic mechanics.
And as a public service announcement, I just want to draw your attention to those “flour-free” breads out there in your local supermarket. These whole grain loaves of supposedly high-fiber goodness suggest that they are unlike regular bread. Made with sprouted grains and hence “flour free”, they lend an impression that they are somehow more natural or better for you than regular sliced bread. But sprouted grains don’t just magically stick together. If they aren’t dried, ground into a flour and then mixed with either yeast or a sourdough culture, the loaf will end up as something that resembles a door-stop. So what do these companies do to get that fluffy loaf we’re all familiar with? They add in lots of gluten to make it rise. Gluten derived from flour. Just take a look at the list of ingredients – gluten is usually number two. Flour-free? Not even a grain of truth to this claim.