Dietary constituents called “FODMAPs” complicate the idea of 
nonceliac gluten sensitivity.

Some people without celiac disease report gastrointestinal intolerance 
to gluten-containing foods. In 2011, Australian researchers conducted 
a controlled-diet study that boosted the case for “nonceliac gluten 
sensitivity” (NEJM JW Gen Med Apr 5 2011). Now, the same group has 
explored whether “FODMAPs” (Fermentable, Oligo-, Di-, 
Monosaccharides, And Polyols) might confound the perceived response to 
a gluten-free diet. FODMAPs are fermentable, poorly absorbed, short-
chain carbohydrates that include fructose, lactose, fructans (found in 
wheat), galactans, and polyol sweeteners.

The trial included 37 patients with irritable bowel syndrome who 
reported gluten sensitivity, and whose evaluations for celiac disease 
were negative. During a 2-week run-in period, all patients followed a 
gluten-free, low-FODMAP diet. Then, in a randomized, double-blind, 
crossover format, each patient received high-gluten, low-gluten, and 
no-gluten diets (1 week for each diet, separated by 2-week washout 
periods).

During the low-FODMAP run-in period, mean symptom scores improved 
significantly. However, symptoms worsened during each of the three 
double-blind treatments — with no differences between the high-
gluten, low-gluten, and no-gluten periods. Twenty-two patients 
repeated the whole study with 3-day (rather than 7-day) food 
challenges, and with dairy products and chemical food additives also 
eliminated from their diets. Again, symptoms worsened just as much 
with the no-gluten diet as with the gluten-containing diets.

COMMENT

In this study of nonceliac patients who reported previous gluten 
sensitivity, a gluten-containing diet was no more likely than a no-
gluten diet to worsen symptoms in the presence of a low-FODMAP diet. 
Because many gluten-containing foods also are high in FODMAPs, the 
authors speculate that improved symptoms with a gluten-free diet 
actually might reflect simultaneous reduction in FODMAP intake. 
However, our understanding of nonceliac gluten sensitivity remains 
incomplete.

Biesiekierski JR et al. No effects of gluten in patients with self-
reported non-celiac gluten sensitivity after dietary reduction of 
fermentable, poorly absorbed, short-chain carbohydrates. 
Gastroenterology 2013 Aug; 145:320. (http://dx.doi.org/10.1053/j.gastro.2013.04.051
) PubMed abstract (Free)Web of Science

Allan S. Brett, MD reviewing Biesiekierski JR et al. Gastroenterology 
2013 Aug.