Food Additives - Do Processed Diets Impact on Gut and Metabolic Health

Study Overview
=================
Brief Summary
-----------------
This dietary intervention study will assess the effect in healthy human volunteers of an E number which is a food additive and commonly used and consumed emulsifier, on gut function, gut inflammation and glucose metabolism. We will be using a powdered soy lecithin product in the food to compare a diet with and without this ingredient.

Detailed Description
-----------------
A dietary intervention study to investigate the effect, in healthy human volunteers, of dietary lecithin (soy lecithin), a commonly used/consumed emulsifier, on markers of gut function particularly bacterial translocation (assessed by measure of venous blood bacterial DNA, circulating lipopolysaccharide [LPS] binding protein and soluble CD14), gut inflammation (assessed by measurement of faecal calprotectin), gut microbiota activity/composition (faecal short-chain fatty acid [SCFA] profile and bacterial diversity [16S ribosomal RNA genes]) and glucose metabolism (measured by oral glucose tolerance test [OGGT], plasma fasted lipids and insulin).

Official Title
-----------------
Investigation of the Effects of Dietary Lecithin on Intestinal Permeability, Bacterial Translocation, Microbiota and Glucose Metabolism

Conditions
-----------------
Gut Health, Metabolic Health

Intervention / Treatment
-----------------
* Dietary Supplement: Soya lecithin


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: • BMI ranging from 27-40 kg/m2 Exclusion Criteria: Antibiotic use within the past 3 months (due to impact on gut microbiota) Current Statin use Current Aspirin use Chronic inflammatory disorders (including rheumatoid arthritis, inflammatory bowel disease) Food allergies or self-reported food sensitivity or intolerance Diagnosis of diabetes Pregnant or breastfeeding Unsuitable veins for blood sampling Inability to speak, read and understand English Unable to comply to alcohol-free diet for 5 weeks Consumption of nutrition supplements Soy allergy or intolerance.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Diet trial with randomised sequence of delivery of two diets.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High-emulsifier to Low-emulsifier<br>Phase 1: No intervention - 7 days food diary (recording at home, usual diet) Phase 2: 14 days high-emulsifier (soya lecithin) low-calorie diet at 100% resting metabolic rate Phase 3: No intervention - 7 days washout with usual diet Phase 4: 14 days low-emulsifier low-calorie diet at 100% resting metabolic rate | Dietary Supplement: Soya lecithin<br>* The lecithin supplement will be soya lecithin granules given as 7.5 g twice daily, incorporated into juices<br>|
| Experimental: Low-emulsifier to High-emulsifier<br>Phase 1: No intervention - 7 days food diary (recording at home, usual diet) Phase 2: 14 days low-emulsifier low-calorie diet at 100% resting metabolic rate Phase 3: No intervention - 7 days washout with usual diet Phase 4: 14 days high-emulsifier( soya lecithin) low-calorie diet at 100% resting metabolic rate | Dietary Supplement: Soya lecithin<br>* The lecithin supplement will be soya lecithin granules given as 7.5 g twice daily, incorporated into juices<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in bacterial translocation | Assessment of change in bacterial translocation by venous blood bacterial DNA measured as responding to pre and post dietary treatment as gene copy number per ml but using more validated universal qPCR primer sets (including total bacteria, phyla- and class-specific primers) | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Faecal calprotectin |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Faecal volatile organics compounds |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Faecal short chain fatty acids |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Faecal bacterial 16S rRNA gene sequencing |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma highly sensitive C-reactive protein |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma soluble CD14 and LPS binding protein |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma fasting blood glucose and up to 3 hours after OGTT |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma fasted insulin profile and up to 2 hours postprandial OGTT |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma fasting lipid profile | Triglycerides, high and low-density cholesterol will be assessed by Kone automated analyser | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion | 
| Plasma trimethylamine-N-oxide (TMAO) |  | Samples collected at baseline and after each 14 day intervention period. Will be assessed no later than 48 months post final volunteer completion |