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Alexa Evenson


Background: Gluten and inulin type fibers have been shown to impact satiety, breath hydrogen, GI symptoms, and properties of different food products. Stress is often thought to play a role in breath hydrogen and gastrointestinal symptoms. Additional lifestyle factors are often related to increased GI symptoms including fiber consumption, increased high-intensity exercise, higher rates of anxiety, and disrupted sleep behaviors.

Objective: The objective of this panel will be to describe the findings from a year-long study examining the impact of consumption of gluten and inulin (a FODMAP) on sensory attributes, satiety, gastrointestinal (GI) symptoms, breath hydrogen, perceived stress, cortisol levels, and a variety of lifestyle factors including anxiety, diet, physical activity, and sleep.

Methods: A blinded, randomized, controlled crossover design was conducted with 24 non-IBS participants. Fasted participants consumed a control low FODMAP smoothie and treatment smoothies that consisted of the low FODMAP base (control) with gluten (5g) or inulin (5g). Cortisol and breath hydrogen were measured at baseline (0), 1, 2, and 3 hours. GI symptoms were measured at baseline (0), 0.5, 1, 1.5, 2, 3, 12, and 24 hours. VAS was collected at baseline (0), 10 min, 30 min, 1, 1.5, 2, and 3 hours. Sensory analysis was completed after the first initial sips of smoothie consumption. Perceived stress, State and Trait Anxiety, and Physical activity were measured for each treatment. Dietary intake and Sleep were analyzed at one time point as these measures assessed behaviors over the past 30 days. Salimetrics ELISA assays were used to determine cortisol values. Variables were analyzed by the Area Under the Curve using the trapezoidal rule, Spearman rho correlation coefficients, and Repeated Measures ANOVA with significance set at p<.05.

Results: Main findings include no differences in breath hydrogen measurements and very little changes in GI symptoms when consuming five grams of gluten or inulin. Lifestyle variables overall did not correlate with breath hydrogen or GI symptoms. There were significant differences found for cortisol values in the control versus inulin and control versus gluten treatment groups. Additional findings will be discussed in detail during the panel.

Conclusion: In healthy adults, consumption of five grams of gluten or inulin did not increase GI symptoms nor breath hydrogen levels indicating there is high tolerance of gluten consumption and inulin consumption. Lifestyle variables did not appear to play a large role in the relationship to GI symptoms. More research is needed to understand the relationship with cortisol and consumption of gluten or inulin.