NCT03581812 - Snack Foods and Their Impact on Gastrointestinal Microbiology, Function and Symptoms

Diet is a crucial target for the improvement of human health. In the modern world, diets are diverse and diet related diseases are becoming more and more common. In particular, it is becoming increasingly apparent that the bacteria that live in the gut are strongly linked to both diet and health. Bacteria in the gut can be beneficial or harmful, and the health of the gut relies on the beneficial bacteria outnumbering the harmful ones. Diet has a great impact on the bacterial composition of the gut. In turn, the gut bacteria play diverse roles in human health, influencing not only the gut but also the health of the immune system, heart and brain. Therefore, optimising the composition of the gut bacterial is vital to human health and wellbeing. It has been shown that snacks between meals contributes 420 - 480 calories per day, almost a quarter of the recommended intake. Therefore, snack choices are an area of diet and lifestyle that have the potential to influence diet and in turn the health of our gut and gut bacteria. We would like to assess the effect of replacing usual snacks with alternative snack foods that we believe have benefits for gut health. The primary aim of the study is to investigate whether the replacement of usual snacks has an effect on gut bacterial composition, specifically the abundance of Bifidobacteria. Secondary aims include the effect of the intervention snacks on additional measures of gut health such as gut transit time, the frequency and consistency of bowel movements and gut symptoms e.g. heartburn, nausea, belching etc. The effect of snack foods on metabolites in the blood (e.g. glucose, insulin, lipids) will also be determined. Finally the impact of snack replacement on mood and quality of life will be assessed.