Investigation of the Effects of Dietary Fibres on the Gut Microbiome in a Transgenerational Cohort

Not Applicable

Completed

Conditions: Gut Health

Interventions: Dietary Supplement: Dietary Fibres Mix
Dietary Supplement: Placebo

Registration Number: NCT05364437

Lead Sponsor: Imperial College London

Brief Summary: Dietary fibres are complex carbohydrates present in fruit, vegetables, grains, and beans which are broken down into smaller molecules (short-chain fatty acids) in the colon by the gut microbiota. Increased intake of dietary fibres is associated with a lower risk of type 2 diabetes, obesity, or heart disease. Despite their health benefits, most people consume half of the daily recommended intake (30 grams) of dietary fibres. This trend has become more apparent in the past few decades with the advent of ultra-processed foods which are poor in dietary fibres. Since this change in dietary habits is more recent, the research team hypothesizes that older generations have a more diverse and better adapted gut microbiota at breaking down dietary fibres compared to younger generations.

The aims of this study are to examine the effects of the daily intake over four weeks of a dietary fibres supplement on the gut microbiota, metabolic profiles, and general health in a transgenerational cohort (grandmother, mother and daughter OR mother and daughter) compared to cellulose control.

Detailed Description: Eligible participants will need to take daily for 14 days a dietary fibre supplement or placebo (depending on the randomisation) followed by wash-out period of 14 days and then followed by taking daily for 14 days the opposite arm of intervention ( cellulose control or dietary fibre supplement). During the study period, participants will come to the research facility to assess the impact of these supplements on their gut microbiota, metabolic profiles and blood glucose, insulin and gut hormone levels.

Recruitment & Eligibility

Status: COMPLETED

Sex: Female

Target Recruitment: 16

Inclusion Criteria

Any of the following groups of people (in direct descent and from the same family) Grandmother, mother and daughter Mother and daughter Grandmother and granddaughter
Age 18-85 (inclusive)
BMI: 18.5-30 kg/m2 (inclusive)
Considering themselves healthy

Exclusion Criteria

Intake of antibiotics in the past 3 months and during the study
Intake of probiotic supplements in the past month and during the study
Regular intake of laxatives in the past month and during the study
Subjects with the following conditions Inflammatory Bowel Disease (IBD) Irritable Bowel Syndrome (IBS) Coeliac Disease Type 2 Diabetes Any type of cancer Autoimmune conditions Conditions that affect the liver Conditions that affect the pancreas
Subjects who require medical intervention in the coming 3 months
Smokers
Shift workers
Gluten and/or lactose intolerance
Pregnant and lactating women
Subjects living in care homes
had weight changes >5% in the preceding 3 months
Subjects who are unable to give informed consent by themselves
Subjects who are currently participating in other clinical trials

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Dietary Fibres Supplement	Dietary Fibres Mix	Dietary fibre mix comprising of inulin, pectin and oat beta-glucan. The mix comes in a powdered form which can be added to participants' food.
Placebo	Placebo	Placebo comprising of cellulose which will come in a powdered form that can be added to participants' food.

Primary Outcome Measures

Name	Time	Method
Stool Short-chain Fatty Acids Production Following Each Intervention Between Mothers and Daughters	14 days	Changes in stool short-chain fatty acids production from baseline after each intervention (cellulose control and dietary fibre supplement) between mothers and daughters

Secondary Outcome Measures

Name	Time	Method
Gut Microbiota Composition Changes Following Each Supplement Intake Between Mothers and Daughters	14 days	Alpha diversity (a measure of the gut microbiota composition) was compared between generations after taking each dietary supplement for 14 days.
Urine Metabolites Comparison Between Mothers and Daughters After Taking Each Supplement	14 days	Changes in urine metabolites types and levels after each generation took both supplements
Stool Metabolites Comparison Between Mothers and Daughters After Taking Each Supplement	14 days	Changes in stool metabolites types and levels between mothers and daughters after taking each supplement. Comparisons done: mothers on dietary fibres supplement versus daughters on dietary fibre supplement and mothers on cellulose control versus daughters on cellulose control
Blood Glucose for Mothers and Daughters After Taking Each Supplement for 14 Days	240 minutes	Postprandial blood glucose levels comparison between mothers and daughters after each generation took each supplement for 14 days. The data is presented as incremental area under the curve.
Blood Insulin Comparison Between Mothers and Daughters After Each Generation Took the Dietary Supplements	14 days	Fasted blood insulin levels comparison between mothers and daughters after each generation took the dietary supplements for 14 days
Blood Insulin Comparison Between Mothers and Daughters After Taking Each Supplement for 14 Days	14 days	Postprandial blood insulin levels comparison between mothers and daughters after each generation took the supplements (dietary fibre and cellulose) for 14 days
Gut Hormones in Mothers Versus Daughters	14 days	Fasted gut hormones levels in mothers after they took the dietary fibre supplement compared to fasted gut hormones in daughters after they took the dietary fibre supplements. Fasted gut hormones levels in mothers after they took the cellulose control compared to fasted gut hormones in daughters after they took the cellulose control.
Gut Hormones in Mothers Who Took Each Dietary Supplement Versus Gut Hormones in Daughters Who Took Each Dietary Supplement	14 days	Postprandial gut hormones levels were compared in mothers after they took the dietary fibre supplements against postprandial gut hormone levels in daughters after they took the dietary fibre supplement. Postprandial gut hormones levels were compared in mothers after they took the cellulose control against postprandial gut hormone levels in daughters after they took the cellulose control.
Blood Glucose in Mothers Compared to Daughters After Taking Each Supplement for 14 Days	14 days	Fasted blood glucose levels in mothers and daughters after each generation took each supplement