RIDGWAY, COLORADO, U.S. — A letter written on behalf of the Wheat Foods Council disputes assertions about modern wheat breeding made in the April issue of National Geographic. In the article “Gut Reactions,” Dr. Joseph A. Murray, M.D., of the Mayo Clinic said gluten overload in Western diets is a reason why U.S. rates of celiac disease have at least quadrupled since the 1950s.

The incidence of celiac currently is estimated at 1 in 141 individuals, the National Geographic story estimated.

The short article prompted a letter by Dr. Brett F. Carver, Ph.D., a professor in the Department of Plant and Soil Sciences at Oklahoma State University in Stillwater. Dr. Carver said that while he was interviewed for the story by the National Geographic, neither he nor anyone else with a view different from that of Dr. Murray’s was quoted in the story.

 “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,” Dr. Carver said in his April 1 letter. “This was a very one-sided, inadequate coverage of an extremely complicated issue.”

In the National Geographic article, Murray said modern wheat planting choices likely exacerbate the problem of celiac disease because farmers and bread makers prefer wheat varieties with higher gluten content. Murray has worked in a research program sponsored by the National Institutes of Health that focuses on celiac disease and gluten sensitivity. He was involved in a study that appeared on-line March 19 in The American Journal of Gastroenterology. The population-based study in Olmsted County, Minnesota, U.S., concluded the incidence of celiac disease has continued to increase in the past decade in the North American population. 

Carver, who also chairs the National Wheat Improvement Committee, said in his letter that the protein content of wheat has maintained an average of 12% since 1979, according to records kept by U.S. Wheat Associates.

“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,” Carver said. “That wheat gluten has maintained a steady state over time is entirely consistent with the multiple end-users for which wheat varieties are developed.”

He added, “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.”

Carver said little difference exists in protein content between modern wheat varieties and older wheat varieties. Wheat starch comprises about 65% to 75% amylopectin and 25% to 35% amylose. Modern durum wheat starch has a similar proportion of amylose as the starch of emmer, its ancient progenitor.

Carver cited five studies on wheat in his letter. In one study from the U.S. Department of Agriculture that appeared on-line Jan. 11 in the Journal of Agricultural and Food Chemistry, results did not support the likelihood that wheat breeding has increased the protein content (proportional to gluten content) of wheat in the U.S. 

Celiac disease is an autoimmune disorder triggered by consuming gluten, a protein found in wheat, barley and rye, according to the National Foundation for Celiac Awareness, Ambler, Pa. One out of every 133 Americans has celiac disease and must avoid eating gluten, according to the association.

A Packaged Facts report from February of 2011 estimated the U.S. market for gluten-free foods and beverages reached $2.6 billion in 2010 after a compound annual growth rate of 30% over the 2006-10 period. The report projected U.S. sales of gluten-free foods and beverages will exceed $5 billion by 2015.