Celiac.com 07/25/2014 - People with non-celiac gluten sensitivity (NCGS) do not have celiac disease, but their symptoms improve when they are placed on gluten-free diets.
They conducted a double-blind cross-over trial on 31 women and 6 men, aged 24-61, with NCGS and irritable bowel syndrome (based on Rome III criteria), but not celiac disease. Researchers randomly assigned participants to groups given a 2-week diet of reduced FODMAPs. Participants were then placed on high-gluten (16 g gluten/d), low-gluten (2 g gluten/d and 14 g whey protein/d), or control (16 g whey protein/d) diets for 1 week, followed by a washout period of at least 2 weeks.
The team measured serum and fecal markers of intestinal inflammation/injury and immune activation, and indices of fatigue. Twenty-two participants were then given either gluten (16 g/d), whey (16 g/d), or control (no additional protein) diets for 3 days. The team evaluated symptoms using visual analogue scales.
Every patient experienced significant improvement in gastrointestinal symptoms during reduced FODMAP intake. Conversely, every patient experienced significantly worse symptoms when their diets included gluten or whey protein. The team observed gluten-specific effects in just 8% of participants. They saw no diet-specific changes in any biomarker.
During the 3-day re-challenge, participants' symptoms increased by similar levels among groups. Gluten-specific gastrointestinal effects were not reproduced.
The end result for this placebo-controlled, cross-over re-challenge study showed no evidence of specific or dose-dependent effects of gluten in patients with NCGS placed on diets low in FODMAPs. The translation is that the team saw no effects of gluten in patients with self-reported non-celiac gluten sensitivity after dietary reduction of fermentable, poorly absorbed, short-chain carbohydrates.