Validation of a food frequency questionnaire to measure intakes of inulin and oligofructose

Abstract

Background and objectives: Inulin and oligofructose are prebiotic carbohydrates associated with numerous health benefits. The aim of this study was to accurately measure inulin and oligofructose intakes and to develop and validate a food frequency questionnaire (FFQ). Subjects and methods: A 7-d semi-weighed food diary (FD) was used to measure intakes in 66 healthy subjects. A 23-item FFQ was developed to measure short-term inulin and oligofructose intakes over the same 7 days and was completed twice on 2 separate days. Results: There were no significant differences in inulin intake (4.0±1.3 vs 4.0±1.4 g/d, P ¼ 0.646) or oligofructose intake (3.8 ± 1.2 vs 3.8 ± 1.3 g/d, P ¼ 0.864) when measured using the 7-d FD or the FFQ. Bland-Altman analysis demonstrated low mean differences between the FD and FFQ in measuring intakes of inulin (À0.09 g/d) and oligofructose (À0.03 g/d). The FFQ categorised 89% of subjects into the same or adjacent tertiles of intakes as the 7-d FD. For the majority of food items, kappa values indicated 'substantial' or 'almost perfect' agreement for assignment of 'portion size' and 'frequency of consumption' between the FFQs completed on separate days. Conclusions: The FFQ is a valid and reliable method for measuring short-term inulin and oligofructose intakes for use in dietary surveys and clinical trials.

Mechanisms and effectiveness of prebiotics in modifying the gastrointestinal microbiota for the management of digestive disorders

“…6 g/100 g), Jerusalem artichoke (16-20 g/100 g) and garlic (9-16 g/ 100 g), but they are also present in smaller amounts in cereals such as wheat (1-4 g/100 g) (12) . However, as wheat is a staple in many western countries, dietary surveys show that it is the major contributor to fructan intake in the United Kingdom (66 %) (13) and the United States (69 %) (14) . Bread contains only a small amount of fructan (0 .…”

“…61-1 . 94 g/100 g depending upon the recipe and cereal source) (15) , but as the most widely consumed food item in the United Kingdom (16) it makes a large contribution to inulin intake (13) . Meanwhile, GOS such as stachyose and raffinose are widely contained and consumed within pulses (17) .…”

Altered gastrointestinal microbiota in irritable bowel syndrome and its modification by diet: probiotics, prebiotics and the low FODMAP diet

“…The compounds identified as having the most evidence for prebiotic effects are the inulin-type fructans (fructo-oligosaccharides, inulin, oligofructose) and galacto-oligosaccharides (GOS), many of which are widely distributed throughout the diet predominantly in grains, vegetables and pulses (88,89) . Total daily dietary intake of inulin and oligofructose in the UK and Europe in healthy individuals is 4 and 10 g/d, respectively (88)(89)(90) . Due to their indigestibility in the human small intestine, prebiotics become available for colonic bacterial fermentation.…”

Prebiotics and gastrointestinal health

“…Inulin-type fructans are found in very large amounts in chicory root (35.7-47.6 g/100 g), which is the most common source for commercial preparations of inulin, but is also present in Jerusalem artichoke (16-20 g/100 g) and garlic (9-16 g/100 g) [6]. ITFs are found in small amounts in cereals such as wheat (1-4 g/100 g), which is actually the most common dietary source in the United Kingdom [7] and the United States [8] due to its widespread consumption.…”