Diet and functional gastrointestinal disorders: A population-based case-control study

BACKGROUND: Diet has been implicated to play a role in functional gastrointestinal disorders (FGID) in clinic-based studies. No population-based data comparing food and nutrient consumption between individuals with FGID and without gastrointestinal symptoms are available. OBJECTIVES: The purpose of this study was to compare the dietary consumption of specific food items and nutrients between individuals with FGID and without symptoms in a population-based sample. METHODS: A validated self-report Bowel Disease Questionnaire was mailed to an age- and gender-stratified random sample of participants aged 20-50 yr from Olmsted County, Minnesota. All patients who reported either FGID symptoms (irritable bowel or dyspepsia) or no gastrointestinal symptoms were invited to undergo a blinded physician interview and physical exam and to complete a validated Harvard Food Frequency Questionnaire. Wilcoxon rank sum tests and logistic regression were used for statistical analysis. RESULTS: In total, 222 of the 260 eligible (85%) subjects participated and 218 provided diet data: 99 were FGID cases and 119 were healthy controls. Cases and controls consumed similar number of servings per week of wheat-containing foods, lactose-containing foods, caffeinated drinks, and fructose-sweetened beverages. Cases were slightly more likely to consume >= 7 servings per week of norepinephrine- and epinephrine-containing foods (57%vs 45%, p= 0.10), but not serotonin- or tryptophan-containing foods. No differences were observed for amount of intake of calories, fiber, protein, iron, calcium, niacin, and vitamins C, D, E, niacin, B-1, B-2, B-6, and B-12. Cases reported consuming more fat (median, 33%vs 31%) and less carbohydrates (median, 49%vs 52%) than controls. CONCLUSIONS: No differences were seen in the consumption of frequently suspected "culprit" foods between community residents with and without FGID symptoms. While symptoms may be due to food sensitivity rather than altered diet composition, the role of fat and perhaps norepinephrine and epinephrine in foods in gut symptoms needs to be studied further.