The Problem with Grains

Most Americans eat grains every day, at every meal. Grains are the backbone of the modern diet and the foundation of the USDA’s food pyramid, yet grains may not support optimal health. Grains tend to displace more nutrient-dense foods like vegetables and fruits in the diet and you may be surprised to find out that they can have adverse effects on blood sugar and hormone levels, leading to weight gain. In addition, all grains contain a variety of compounds that can damage the lining of the gastrointestinal tract, initiate an immune response and promote inflammation.

Identifying Grains

The term “grain” refers to domesticated grasses in the Gramineae family. This includes wheat (including Einkorn, Emmer, Kamut, Semolina, Durum, Triticum aestivum), brown rice, corn, millet, teff, oats, barley, rye, spelt, triticale and sorghum. Quinoa, amaranth, wild rice and buckwheat are not true grains, but have similar properties to grains and can promote some of the same health complications.

Grains Can Cause Weight Gain

All of the grains listed above (including quinoa, wild rice and buckwheat) are composed mostly of carbohydrates, and are nutrient-poor in comparison to meats, vegetables and fruits.1 Because of their high carbohydrate content, grains can elevate levels of blood glucose and insulin, leading to weight gain.2 Refined grains, like white rice and flours, are the worst offenders. These types of grains, which have little to no fiber, are broken down into sugar very rapidly through digestion and flood the bloodstream with glucose.3,4 The result is a blood sugar spike, followed by a spike in the hormone insulin, whose job is to help glucose enter the body’s cells. In a healthy individual (as opposed to an insulin-resistant individual), this insulin spike causes blood glucose to decrease rapidly, potentially causing hypoglycemia 2,3 (low blood sugar) accompanied by release of the hormone cortisol.5 This pattern of spiking first insulin then cortisol, also known as the blood sugar rollercoaster, is stressful on the body and leads to fat storage and weight gain.2,3

Grains Can Age the Body

An important consequence of elevated blood sugar is physical aging of the body. Because glucose molecules are sticky, they attach to structural proteins in our body (like collagen in bones, skin and arteries, or LDL cholesterol molecules) without the action of an enzyme. Over time, this non-enzymatic reaction results in a molecule called an Advanced Glycation End-product (AGE) that damages tissues and disrupts normal functions of the body.6 AGEs are largely responsible for wrinkly skin, brittle bones, hardened arteries and other signs of aging, and they form at an accelerated pace when blood sugar is elevated.6

Grains Can Cause Digestive Distress, Inflammation and an Immune Reaction

Digestive dysfunction, inflammation and immune activation can all be caused by a family of proteins called prolamins, found in all grains. Prolamins are rich in the amino acids proline and glutamine and they resist digestion in the human gastrointestinal tract (GI tract). When these in-tact proteins reach the small intestine, they activate the gut-immune system (60-80% of the immune system is in the gut), which can damage the intestinal lining and allow undigested food molecules to escape into the bloodstream.7,8,9 When these food molecules enter the bloodstream, they initiate an even greater immune response.9,10 This cascade reaction to prolamins has been well-studied in individuals with Celiac Disease, an autoimmune condition that results from exposure to gliadin, the prolamin found in gluten. Gliadin has also been implicated in the development of other autoimmune diseases including Type I Diabetes.9 Research shows fermenting grains initiates enzymatic reactions that predigest the prolamins, allowing the grain to be used more easily by the body.11 For a fermented sourdough bread recipe, see the book Wild Fermentation by Sandor Ellix Katz. But note that it may be wise to limit even fermented grains in order to make room for more nutrient-dense foods, like vegetables and fruit.

Limiting or eliminating grains in the diet can be a big step toward optimal health. This change supports healthy digestion and helps us to maintain healthy levels of blood sugar and hormones, which positively impacts every bodily system. For those individuals that need extra carbohydrates in their diets, try adding more moderate and higher carbohydrate organic vegetables and fruits such as sweet potatoes, potatoes, winter squash, beets, apples, bananas, grapes, and mangos. These foods provide a concentrated source of nutrients in addition to complex carbohydrates, and they lack the problematic constituents found in grains. However, if eliminating grains from the diet is not an option for you, proper preparation techniques like fermentation can minimize the potentially damaging effects of grains consumption.

References


  1. “Origins and evolution of the Western diet: health implications for the 21st century.” American Journal of Clinical Nutrition. 81.2 (2005): 341-354.
  2. Taubes, Gary. The Carbohydrates Hypothesis II. Good Calories, Bad Calories. New York: Anchor Books, 2011. Print
  3. Challem, Jack. NGVC Customer Literature File “Overeating and Overweight.”
  4. Foster-Powell, Kay, Holt, Susanna, Brand-Miller, Janette. ―International table of glycemic index and glycemic load values: 2002.‖ The American Journal of Clinical Nutrition 76.1 (2002): 5-56. http://www.ajcn.org/content/76/1/5.full.pdf+html
  5. Plonk, James, Bivens, Carl, et al. “Inhibition of Hypoglycemia-Induced Cortisol Secretion by the Serotonin Antagonist Cyproheptadine.” The Journal of Clinical Endocrinology and Metabolism 38.5 (1974): 836-840.
  6. Bernstein, Richard. Dr. Bernstein’s Diabetes Solution. New York: Little, Brown and Co., 2007. 446. Print.
  7. Drago, Sandro et al. "Gliadin, Zonulin and Gut Permeability: Effects on Celiac and Non-celiac Intestinal Mucosa and Intestinal Cell Lines." Scandanavian Journal of Gastroenterology 41 (2006). Web. 13 Mar. 2012.
  8. Lammers, K., R. Lu, J. Brownley, et al. "Gliadin Induces an Increase in Intestinal Permeability and Zonulin Release by Binding to the Chemokine Receptor CXCR3." Gastroenterology 135.1 (2008): 194-204. Print.
  9. Visser, Jeroen, Jan Rozing, Anna Sapone, Karen Lammers, and Alessio Fasano. "Tight Junctions, Intestinal Permeability, and Autoimmunity." Annals of the New York Academy of Sciences 1165.1 (2009): 195-205
  10. Lipski, Elizabeth. Digestive Wellness. New York: McGraw-Hill, 2005. 82. Print
  11. Loponen, Jussi, Kanerva, Paivi, et al. Prolamin Hydrolysis and Pentosan Solubilization in Germinated-Rye Sourdoughs Determined by Chromotographic and Immunological Methods. Journal of Agricultural and Food Chemistry 57.2 (2009): 7456-753.