Washington, DC, USA
June 21, 2012
by Judi Adams, MS, RD, President, Wheat Foods Council
Source: U.S. Wheat Associates newsletter
Editor’s Note: Although Ms. Adams originally wrote this article for U.S. consumers, its information is relevant to U.S. wheat buyers, millers, wheat food processors and consumers around the world.
Wheat has long been a major contributor of nutrients to the American diet through consumption of bread, rolls, cereal and pasta. Grains contribute over 70 percent of the folic acid/folate, 50 percent of the iron and 39 to 60 percent of the three major B vitamins, as well as many others1, to the American diet (see attached chart). Approximately 70 percent of the grains consumed in America are wheat, so it plays a significant role in delivering those nutrients. In addition, wheat delivers 20 percent of the calories consumed by all human beings on the planet.
Unfortunately, the strength of old wives’ tales, myths and the new power of viral “group think” appear to have more power than scientific fact when consumers consider the nutritional value of wheat and other grains.
Perhaps the oldest tales purport that bread and grains are “fattening,” yet the science shows just the opposite. As far back as 1997, Harvard University colleagues published a paper in Diabetes Care showing that men who consumed 6.1 slices of white bread per week had BMIs (body mass indexes) 0.4 units less than men who consumed 1.9 slices per week2. And carbohydrates in general do NOT cause obesity. In 2009, the Canadian Community Health Survey 2.2 concluded, “Consuming a low-carbohydrate (approximately 47 percent energy) diet is associated with greater likelihood of being overweight or obese among healthy, free-living adults…lowest risk may be obtained by consuming 47 percent to 64 percent energy from carbohydrates”3. The National Health and Nutrition Examination Survey, an long-term survey conducted by the Centers for Disease Control and Prevention supports this conclusion.
Wheat, barley and rye all contain the protein gluten that cannot be digested by those with celiac disease (an autoimmune response to gluten by people who are genetically predisposed to this condition) or who are gluten sensitive. In the United States, less than one percent of the population has celiac disease and about six percent may have gluten sensitivity.
In spite of that low percentage, Mintel’s Global New Products Database found that international product launches with a gluten‐free claim nearly tripled in 2011 to roughly 1,700 products as compared to 20074.
Gluten-free diets are very strict and limiting and should remain a therapeutic diet prescribed for a serious medical condition. Unless an individual is diagnosed with celiac disease or gluten sensitivity, there is no reason to go “gluten free.” If you suspect you might have trouble digesting gluten-containing grains, a visit to a physician for testing is recommended. If the diagnosis is celiac disease, a gluten-free diet is the only treatment available. If gluten sensitivity is suspected, there is no definitive test currently available to diagnose this condition. But it is important to rule out the more serious condition (celiac disease) and possibly other conditions. There has been an increase in celiac disease in the past 50 years. There are many theories as to why, and research is ongoing, but none have been proven. What we do know is that a vast majority of people can consume gluten without any adverse effects.
Unfortunately, this medically necessary diet for those afflicted with celiac disease or gluten sensitivity has become a fad diet for many celebrities and other looking to lose weight, “cleanse their system,” “feel better,” etc. There is no research showing any of these benefits and there are actually many downsides to eating gluten-free if you don’t have to. It is expensive, inconvenient and usually less nutritious because the substitutes for wheat, barley and rye are often not whole grains and rarely enriched with the B vitamins and iron found in wheat products. Naturally occurring resistant starches found in wheat are known to promote a favorable mix of colon bacteria5, and these interactions in the colon may protect the gut from some cancers, inflammatory conditions, and cardiovascular disease6,7.
Many people may also think they are “allergic” to wheat. In fact, less than one percent of Americans have diagnosed wheat allergies. They are primarily children8, but most out-grow their allergies by the teenage years.
Grains, and wheat in particular, are a major source of fiber in the U.S. diet. Some fiber components found in wheat, corn, millet and rice as well as barley and oats have been shown to improve glucose tolerance, which can lead to preventing insulin resistance and diabetes9. Higher fiber intake has also been associated with lower rates of colon cancer and diverticular disease in large cohort studies. Fiber is recommended both to prevent and to treat diverticular disease10, 11,12.
Refined/enriched grains are often blamed for causing diseases or being nutritionally inferior. However, a recent Nutrition Reviews article looked at 135 relevant studies that were published between 2000 and 201013. The author concluded, “The totality of evidence shows that consumption of up to 50 percent of all grain foods as refined-grain foods (without high levels of added fat, sugar or sodium) is not associated with any increased disease risk.” This 50 percent recommendation mimics the 2010 Dietary Guidelines for Americans.
Last year the Centers for Disease Control and Prevention credited enriched grains, fortified in the United States with folic acid since 1998, with preventing 36 percent of neural tube birth defects (spina bifida) in America. They listed this accomplishment as one of the top 10 most significant health initiatives in the 21st century14. To learn more about the global effort to enrich grains to prevent birth defects, visit the Flour Fortification Initiative on the Web at http://www.sph.emory.edu/wheatflour/index.php.
The science shows wheat and grains are important carriers of nutrients in the American diet. Old wives’ tales, myths and internet spam are not credible sources for nutrition information.
References:
1. USDA CNPP Nutrient Content of the US Food Supply, July 2011
2. Salmeron et al. Dietary fiber, glycemic load, and risk of NIDDM in men. Diabetes Care 1997; 20: 545-550.
3. J Am Diet Assoc. 2009;109:1165-1172.
4. http://www.mintel.com/press-centre/press-releases/822/could-you-be-gluten-intolerant-some-may-be-suffering-in-silence. Feb 2012
5. Gibson GR. Prebiotics as gut microflora management tools. J Clin Gastroenterol 2008; 42(suppl 2):S75-S79.
6. Fava F, Gitau R, Lovegrove J, Tuohy KM. The gut microflora and lipid metabolism: implications for human health. Curr Med Chem 2006;13:3005–3021.
7. Rastall RA, Gibson GR, Gill HS, et al. Modulation of the microbial ecology of the human colon by probiotics, prebiotics and synbiotics to enhance human health: an overview of enabling science and potential applications. FEMS 2005;52:145–152.
8. Inomata N. Wheat allergy. Curr Opin Allergy Clin Immunol 2009;9:238-243.
9. Lopez HW, Levrat MA, Guy C, Messager A, Demigne C, Remesy C. Effects of soluble corn bran arabinoxylans on cecal digestion, lipid metabolism, and mineral balance (Ca, Mg) in rats. Journal of Nutritional Biochemistry 10:500-509,1999.
10. Bingham SA, Day NE, Luben R, Ferrari P, Slimani N, Norat T, Clavel-Chapelon F, Kesse E, Nieters A, Boeing H, Tjønneland A, Overvad K, Martinez C, Dorronsoro M, Gonzalez CA, Key TJ, Trichopoulou A, Naska A, Vineis P, Tumino R, Krogh V, Bueno-de-Mesquita HB, Peeters PH, Berglund G, Hallmans G, Lund E, Skeie G, Kaaks R, Riboli E; European Prospective Investigation into Cancer and Nutrition. Lancet (9368):1496-501,2003.
11. Crowe FL, Appleby PN, Allen NE, Key TJ. Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians. BMJ. 343:d4131, 2011.
12. Sansbury LB, Wanke K, Albert PS, Kahle L, Schatzkin A, Lanza E; Polyp Prevention Trial Study Group. The effect of strict adherence to a high-fibre, high-fruit and -vegetable, and low-fat eating pattern on adenoma recurrence. Am J Epidemiol. 2009 Sep 1;170(5):576-84. Epub 2009 Jul 30.
13. Williams, PG. Evaluation of the evidence between consumption of refined grains and health outcomes. Nut Reviews, 70 (2) 80-99. Feb. 2011.
14. CDC. Ten Great Public Health Achievements – U. S. 2001-2010. CDC MMWR. (19) 619-613, May 2011
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