April 1, 2013
Chris Johns, Editor-in-Chief
National Geographic Magazine
Dear Mr. Johns:
As someone who has long respected the integrity and accuracy of the National Geographic, I was very disappointed to read the article, “Gut Reactions” in your April issue. This was a very one-sided, inadequate coverage of an extremely complicated issue.
Your research editor, Elizabeth Snodgrass, contacted me and several others in the industry to get the accurate facts on modern wheat breeding. Either she misinterpreted the facts, or perhaps Johnna Rizzo decided to make the article very one-sided to match the current urban myths on the subject.
There is very little difference between modern wheat and older varieties when it comes to protein content. Numerous peer-reviewed journal articles show that the composition of wheat has not changed. The proportion of protein and starch in wheat has remained stable. Wheat starch comprises around 65-75 percent amylopectin and 25-35 percent amylose. Modern durum wheat starch possesses a similar proportion of amylose as the starch of its ancient progenitor, emmer.1-5 According to records kept by U.S. Wheat Associates, the protein content of wheat has maintained an average of 12 percent since 1979. It is true that more vital wheat gluten is in our food supply than in the past, but that has nothing to do with the gluten content inherent in modern wheat.
That wheat gluten has maintained a steady state over time is entirely consistent with the multiple end-uses for which wheat varieties are developed. Protein content in wheat, and hence gluten content, varies by wheat market class and by varieties within a market class, and can be greatly influenced in all directions via climatic shifts and soil fertility level. The diversity of our diet alone, from cereal to pasta to cake, ensures a broad sampling of protein amount and functionality that occurs naturally in the wheat genome.
Urban myths have led some American consumers to believe that wheat has been genetically engineered and is no longer the same wheat that ancient civilizations – or even our grandparents – used to eat.
Wheat, as the majority of all food plants in the world, has undergone farmer selection and traditional breeding over the years. The hybridization that originated bread wheat occurred 8,000 to 10,000 years ago, and the hybrididization event responsible for durum wheat is even much older. All cultivated wheats, modern or old heirloom varieties, have these hybridization events in common, so that the kinds of protein (and gluten) present in today’s varieties mirrors the composition present throughout the domestication of wheat.
Here is one of the reasons why. A fascinating part of modern wheat breeding is the continued dependence on wild, ancestral forms as valuable genetic resources for improving adaptation of wheat worldwide. I am referring to Triticum dicoccoides (emmer), T. tauschii (a goatgrass progenitor of modern wheat), and T. monococcum (einkorn), just to name a select few. When these ancestral forms are used – and they indeed are to shore up our defense against a new virulent form of stem rust as only one example – breeders will invariably introduce genome segments that may or may not encode a myriad of gluten proteins. This is simply to say that breeders operate in a huge genetic melting pot of diversity that is reflected in our varieties today.
You chose to talk to one celiac disease researcher who believes wheat could be responsible for the increase in celiac detection. There are others, specifically Stefano Guandalini, MD, at the University of Chicago Celiac Center, and co- chair of the upcoming 15th International Celiac Disease Symposium in September 2013, who will tell you differently.
It is important to realize that people do not get celiac disease because of increased contact with gluten. Only those who have a celiac disease gene can acquire celiac disease. It is not proven, but one theory suggests that increased exposure to gluten may cause the disease to manifest itself in genetically at-risk individuals.
I suspect that some employees at National Geographic know that all auto-immune diseases have dramatically increased in the last 20 years including autism, multiple sclerosis, diabetes, etc. There are numerous theories as to why this has happened but the most prominent theory is the change in our gut microbiomes.
Bottom line, you have an opportunity to be a voice for common sense and reason about providing food to the world. Please feel free to contact me should you have any questions or desire additional information.
Brett F. Carver, PhD
Chair, National Wheat Improvement Committee
Department of Plant and Soil Sciences
Oklahoma State University
368 Agricultural Hall
Stillwater, OK 74078-6028
1) Guzman, C. et al. (2010). Amylose content and starch properties in emmer and durum
wheat lines with different waxy protein composition. Journal of the Science of Food and2) Brandolini, A. et al. (2008). Chemical composition and pasting properties of einkorn
Agriculture, 91, 1625–1629. doi:10.1002/jsfa.4358
(Triticum monococcum L. subsp. monococcum) whole meal flour. Journal of Cereal Science,3) Kasarda DD. (2013). Can an Increase in Celiac Disease be Attributed to an Increase in the
47, 599-609. doi:10.1016/j.jcs.2007.07.005 Note: this study shows that the relative
abundance of amylose in this ancient wheat is largely the same as we find in modern wheat.
Gluten Content of Wheat as a Consequence of Wheat Breeding. J Agric Food Chem.4) Shewry, P.R. et al. (2011). Relationship between the Contents of Bioactive Components in
Grain and the Release Dates of Wheat Lines in the Healthgrain Diversity Screen. Journal of5) Underdahl, J.L. et al. (2008). Quality Trait Variation in Major Hard Red Spring Wheat
Agricultural and Food Chemistry, 59, 928-933. doi:10.1021/jf103860x
Cultivars Released in North Dakota Since 1968. Cereal Chemistry, 85, 507-514.