Although gluten is not generally believed to cause harm to individuals without celiac disease, gluten-free diets have become increasingly popular, as gluten avoidance has been suggested to benefit cognitive health among the general population. However, in a recent study, researchers have reported that in the absence of celiac disease, restriction of dietary gluten to maintain cognitive function is not warranted. The research has been published in the JAMA Network Open on May 21, 2021.
Previous study findings showed gluten-free diet for a year resulted in mucosal healing and modest improvement in cognitive performance in patients with celiac disease. However, data are lacking in individuals without celiac disease. Therefore, Dr Yiqing Wang and his team conducted a study to examine whether gluten intake is associated with cognitive function in women without celiac disease.
In this cohort study, the researchers assessed the daily gluten intake of nearly 13,500 US women who participated in the longitudinal, population-based Nurses' Health Study II and had not previously or subsequently been diagnosed with celiac disease. They tracked study participants' gluten intake over 25 years and tested their cognitive function at the end of that period. They then compared cognitive function test scores for women with the highest levels of gluten intake in their diets to those with the lowest. They used validated Cogstate Brief Battery to assess three standardized cognitive scores such as:
(1) psychomotor speed and attention score,
(2) learning and working memory score and
(3) global cognition score. Higher scores indicated better performance.
Key findings of the study were:
After controlling for demographic and lifestyle risk factors in linear regression, the researchers found no significant differences in standardized cognitive scores by quintile of gluten intake across the highest and lowest quintiles of gluten intake (psychomotor speed and attention: −0.02; learning and working memory: 0.02; global cognition: −0.002).
Similarly, they found that these associations were not materially altered in sensitivity analyses that excluded women who had reported cancer or dementia diagnosis or had not completed all dietary assessments.
"People without a history of celiac disease should not modify their gluten intake under the belief that it will somehow prevent cognitive decline," said co-author Dr Andrew T. Chan in an interview.
The authors concluded, "In this study, long-term gluten intake was not associated with cognitive scores in middle-aged women without celiac disease. Our results do not support recommendations to restrict dietary gluten to maintain cognitive function in the absence of celiac disease or established gluten sensitivity."
For further information:
jamanetwork.com/journals/jamanetworkopen/fullarticle/2780271