The Effect of Functional Dairy Products Enriched With Dietary Fibers on Human Health and Gut Microbiota

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Dietary Supplement: Test product; Dietary Supplement: Control product

• Registration Number: NCT04811157
• Lead Sponsor: Center of Food and Fermentation Technologies

Brief Summary

The purpose of this dietary intervention is to study the effects of dietary fibers on the gut microbiota and use yoghurt as the carrier.

Hypothesis 1: Intake of dietary fibers improves the blood lipid profile of the participants.

Hypothesis 2: Intake of dietary fibers stabilizes the gut microbiome (e.g., low diversity) of the participants, improves gut health and normalizes gastrointestinal function and bowel habits.

Detailed Description

The study design is a parallel randomized, prospective, pre-post intervention trial. The main goal of this study is to investigate the effect of the dietary fibers in an unsweetened yoghurt. Fermented dairy products have naturally a very low dietary fiber content, but such products can be supplemented with variety of dietary fibers and promote the growth of beneficial gut bacteria. Also, as fermented milk products contain live bacteria, it is possible that prebiotic fibers could support the growth of the starter-culture based strains in the human gut.

PRE-STUDY EVALUATION AND TESTING

1. Complete pre-study questionnaire

2. Complete orientation to the study and provide voluntary consent to join the study

3. Collection of coded intervention products, sampling supplies, and instructional materials 0-WEEK QUESTIONNAIRE AND LABORATORY VISIT

1. Record food intake and gastrointestinal function for 3 days 2. Collect health data and provide a 3-day food frequency questionnaire 3. Provide a stool and blood sample at the laboratory 2-WEEK QUESTIONNAIRE AND LABORATORY VISIT

1. Record food intake and gastrointestinal symptoms for 3 days

2. Collect health data and provide a 3-day food frequency questionnaire

3. Provide a stool and blood sample at the laboratory BLOOD SAMPLE ANALYSES

1. Provide the blood sample at the laboratory in the morning in an overnight fasted state.

DIETARY INTERVENTION

1. Daily intake of a test or control product for two weeks.

Study Timeline

• Study Start: 2020-04-01
• Primary Completion: 2020-08-31
• Study Completion: 2020-08-31
• Status Verified: 2021-03
• Study First Submitted: 2021-03-18
• Study First Submitted QC: 2021-03-19
• Last Update Submitted: 2021-03-19
• Study First Posted: 2021-03-23
• Last Update Posted: 2021-03-23

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 90

Inclusion Criteria

• Age 25-55
• Normal bowel function
• Regular consumer of dairy products, willing to consume dairy products daily for 2 weeks
• Ability to provide a signed written informed consent
• Willing to provide stool and blood specimens 2 times over the 2-week study period

Exclusion Criteria

• Diagnosed history of chronic diseases including coronary heart disease, stroke, cancer, type 1 or 2 diabetes mellitus, inflammatory bowel disease, gastritis, autoimmune disease, or rheumatoid arthritis
• Medication: statins, blood pressure medications, antidepressants, other prescription medications
• History of bariatric operation, removal of the gallbladder.
• Food allergies, lactose intolerance
• Recent (previous 3 months) use of antibiotics
• Intake of highly dosed pre- or probiotics 2 weeks prior and during the study
• Current pregnancy or breastfeeding
• Volunteers showing previously unrecognized illness will also be excluded
• Individual unable to give informed consent

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Test group	Test product	Healthy adults consuming test product
Control group	Control product	Healthy adults consuming control product

Primary Outcome Measures

Name	Time	Method
Evaluation of blood lipid profile	14 days	Triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol pre- and post-dietary intervention in plasma (mmol/L).
Evaluation of the intestinal microbiota	14 days	Fecal microbiota analysis based on the 16S rRNA sequencing pre- and post-dietary intervention.
Evaluation of blood glucose levels	14 days	Fasting glucose pre- and post-dietary intervention in plasma (mmol/L).

Secondary Outcome Measures

Name	Time	Method
Evaluation of the defecation timing	14 days	Evacuation timing 3 days before sampling pre- and post-dietary intervention.
Evaluation of the stool form	14 days	Stool form will be assessed using a validated 7-point scale called Bristol Stool Form Scale pre- and post-dietary intervention.
Evaluation of the blood vitamin D status	14 days	25-OH vitamin D pre- and post-dietary intervention in plasma.
Evaluation of the defecation frequency	14 days	1. Evacuation frequency during 3 days pre- and post-dietary intervention.; 2. Evacuation frequency (number of bowel movements per week) pre- and post-dietary intervention.
Evaluation of the gastrointestinal symptoms	14 days	Frequency and severity of the gastrointestinal symptoms (Constipation, Diarrhea, Bloating, Flatulence, Cramps, Stomach pain). Scale of frequency: Never, Less than 10 times a year, Once a month, Once a week, Every day. Scale of severity: I do not have any gastrointestinal symptoms, Mild (does not disturb), Moderate, Strong (disturbs considerably).

Trial Locations

Locations (1)

Center of Food and Fermentation Technologies; 🇪🇪 Tallinn, Harjumaa, Estonia