Resistant Starch Intake Is Low in Australian Adults With Irritable Bowel Syndrome Who Follow a Low FODMAP Diet

OBJECTIVES: This observational study aimed to assess dietary intake, including resistant starch (RS) in adults with Irritable Bowel Syndrome (IBS), who follow a habitual diet low in Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP) (LFD). METHODS: Twenty-six participants in Perth, Western Australia with IBS (23 females, aged mean ± SD 37 ± 13 years with a Body Mass Index of 23 ± 3 kg/m(2)) had FODMAP content assessed using the Monash University Comprehensive Nutrition Assessment Questionnaire and dietary RS from 3-d weighed food diary analysed using published RS values for Australian foods incorporated into a dietary database analysed using FoodWorks 10 (Xyris, QLD, Australia). Descriptive statistics and correlation analysis were performed using SPSS v27(IBM, 2017). RESULTS: Out of all participants 35% (n = 9) were on a LFD > 1 year, median 12 months (Interquartile range = 21.8 months), and 77% (n = 20) were at the personalized phase. Median FODMAP intake was 9.6 ± 9.4 g/d and positively associated with the length of time on a LFD, partial correlation (adjusted with BMI and age) was 0.541 (P = 0.003). A therapeutic FODMAP intake <12 g/d (unvalidated) was achieved by 73% (n = 19) of participants. Energy from fat mean ± SD 38.1 ± 9.6% and saturated fat 12.4 ± 3.9% were above Australian recommendations at 20–35% and <10%, respectively. Mean energy contributed by carbohydrates, 36 ± 9.2% was below recommendations (45–65%). Despite the avoidance of plant-based foods high in FODMAP, dietary fibre intake was 20.7 ± 7.4 g/d, equivalent to national Australian studies of adults but less than dietary targets (male 38 g, female 28 g). Habitual RS consumption was 2.1 ± 1.2 g/d, lower than estimations of both typical Australian diets (3.7 (1.9–5.6) g/d) and a LFD study providing all meals (6.9 (3.6–10.3 g/d). Consumptions of vegetables and fruit were 3.9 ± 2.9 and 0.3 ± 1.6 serves/d respectively, and less than the Australian recommendations of 5–6 and 2 serves/d respectively. CONCLUSIONS: This is the first study in IBS patients to measure RS intake in habitual LFD. Australian adults with IBS consuming a LFD should integrate additional RS sources when personalising their LFD. On the premise that food consumed will not exacerbate IBS symptoms, patients on a LFD should increase the intake of vegetables and fruits based on personal tolerance. FUNDING SOURCES: Edith Cowan University.