Impact of Dietary Fibre Consumption on Digestive Comfort

Impact of Dietary Fibre Consumption on Digestive Comfort

The purpose of this randomised, placebo-controlled, cross-over study is to compare the impact different fibres have on gastrointestinal symptoms when they are consumed individually or as mixtures in healthy adults. The impact of different fibres on the experience of symptoms and stool parameters will be assessed.

Global sugar consumption is higher than recommended and there are suggestions that this may be linked to the development of non-communicable diseases including dental caries, and obesity. There are many alternatives to sugars that can be used in foods including certain dietary fibres such as inulin or fructo-oligosaccharides. Most dietary fibres can be fully or partially fermented in the colon by the commensal microbiota, producing beneficial bioactive molecules. However, the rapid production of gas during the fermentation of highly soluble fermentable fibres may cause undesirable symptoms for some people. Dietary exposure to the fibres used in food reformulation, including inulin and soluble corn fibre, is increasing and the impact this may have on gastrointestinal symptoms is unclear. The impact of fibres with different physicochemical characteristics and fermentabilities may differ when consumed in mixtures compared to individually.

The aim of this study is to investigate the impact different fibres have on gastrointestinal symptoms when they are consumed individually or as mixtures and how this relates to the composition of the stool.

Inclusion criteria:

• Self-reported healthy adults (aged 18-65y)
• Non-smokers

Exclusion criteria:

• Individuals with any allergies or conditions affecting bowel health e.g. inflammatory bowel disease (Crohn's disease or ulcerative colitis), irritable bowel syndrome, coeliac disease or diverticular disease
• Individuals who are pregnant or are trying to get pregnant
• Individuals with any food allergies
• Individuals who have taken antibiotics in the past 3 months
• Individuals who regularly take medication that may modify gastrointestinal function e.g. prokinetic agents (e.g. metoclopramide), antiemetics, constipation treatments (e.g. lactulose, polyethylene glycol)
• Individuals who consume ≥25g fibre per day