BOSTON — Promoting gluten-free diets among people without celiac disease should not be encouraged, according to a study appearing on-line May 3 in The BMJ. Long-term dietary intake of gluten was not associated with the risk of coronary heart disease, according to the study, while avoiding gluten may reduce consumption of whole grains.
Gluten, a storage protein, is found in wheat, rye and barley. It triggers inflammation and intestinal damage in people with celiac disease.
The study involved 64,714 women in the Nurses’ Health Study and 45,303 men in the Health Professionals Follow-up Study without a history of coronary heart disease who completed a food frequency questionnaire in 1986 that was updated every four years through 2010. The study excluded people who reported a diagnosis of celiac disease. People were divided into five groups based on gluten intake.
During 26 years of follow-up encompassing 2,273,931 person years, 2,431 women and 4,098 men developed coronary heart disease. People in the lowest fifth of gluten intake had a coronary heart disease incidence risk of 352 per 100,000 person years, which compared to 277 per 100,000 person years for people in the highest fifth of gluten intake.
Gluten intake correlated positively with whole grain intake and refined grain intake.
“Whole grain intake has been found to be inversely associated with coronary heart disease risk and cardiovascular mortality,” the study said. “These findings underscore the potential that people who severely restrict gluten intake may also significantly limit their intake of whole grains, which may actually be associated with adverse cardiovascular outcomes.”
Gluten did not correlate strongly with sodium intake. Gluten correlated with glycemic index.
Researchers from the Columbia University College of Physicians and Surgeons in New York, Harvard Medical School in Boston and the Harvard T.H. Chan School of Public Health in Boston conducted the study. The American Gastroenterological Association, the Massachusetts General Hospital and the National Institutes of Health all provided funding.