Gastrointestinal tolerance and utilization of agave inulin by healthy adults

Little clinical research exists on agave inulin as a fiber source. Due to differences in botanical origin and chemical structure compared to other inulin-type fibers, research is needed to assess gastrointestinal (GI) tolerance following consumption. This study aimed to evaluate GI tolerance and utilization of 5.0 and 7.5 g per day of agave inulin in healthy adults (n = 29) using a randomized, double-blind, placebo-controlled crossover trial consisting of three 21 day periods with 1 week washouts among periods. GI tolerance was assessed via daily and weekly questionnaires, three fecal samples were collected on days 16-20 of each period, and breath hydrogen testing was completed on the final day of each treatment period. Survey data were compared using a generalized linear mixed model. All other outcomes were analyzed using a mixed linear model with a repeated measures procedure. Composite GI intolerance scores for 5.0 and 7.5 g treatments were both greater (P < 0.05) than control, however, scores were low, with means of 0.4, 1.9, and 2.3 on a 0-12 point composite scale for 0, 5.0, and 7.5 g treatments, respectively. There were slight increases (P < 0.05) in bloating, flatulence, and rumbling frequency with 5.0 and 7.5 g agave inulin. Abdominal pain and rumbling intensity were marginally greater (P < 0.05) with 7.5 g. Bloating and flatulence intensity increased (P < 0.05) with 5.0 g and 7.5 g. Agave inulin did not affect diarrhea (P > 0.05). Number of bowel movements per day increased, stools were softer, and stool dry matter percentage was lower with 7.5 g (P < 0.05). Breath hydrogen concentrations increased (P < 0.001) from 5-8 hour postprandial when participants consumed agave inulin compared to control. These data demonstrate that doses up to 7.5 g per day of agave inulin led to minimal GI upset, do not increase diarrhea, and improve laxation in healthy young adults.