Effect of the Sustainable Diet on Gut Microbiota and the Metabolome: a Randomised Crossover Study

Not Applicable

Completed

• Conditions: Microbiota; Nutrition, Healthy
• Interventions: Other: Western diet; Other: Plant-based diet

• Registration Number: NCT05231317
• Lead Sponsor: University of Ulster

Brief Summary

Unhealthy diets are closely linked to non-communicable diseases and constitute higher risk of morbidity and mortality than unsafe sex, alcohol, tobacco and drugs use combined. According to the World Health Organization (WHO), a healthy diet follows a plant-based pattern with low quantities of red meat and a low simple sugar intake. It would also reduce anthropological ecologic impact. We hypothesize that a plant-based diet will beneficially modify the gut microbiota and metabolome, influencing also Trimethylamine N-oxide (TMAO), a metabolite associated to CVD.

This study has a randomized single blind crossover design that compares a plant-based diet towards a control western diet. It is applied to volunteers aged 18-70 years, N=20. Each dietary intervention (plant-based and western) would last for 16 consecutive days separated by a minimum of 7 weeks washout period (intervention 1-washout-intervention 2). Samples of blood urine and faeces will be collected at day 1 and 14 of each intervention. On day 14 will be performed L-carnitine challenge with 1200mg of L-carnitine to test the levels of TMAO), in for the next 2 consecutive days (24h and 48h post treatment).

Detailed Description

Not available

Study Timeline

• Study Start: 2021-07-02
• Primary Completion: 2021-12-17
• Study Completion: 2021-12-17
• Status Verified: 2022-01
• Study First Submitted: 2022-01-28
• Study First Submitted QC: 2022-01-28
• Last Update Submitted: 2022-01-28
• Study First Posted: 2022-02-09
• Last Update Posted: 2022-02-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Free-living, apparently healthy adults
• Bmi>18
• Aged 18-70 years at recruitment
• Non-smokers

Exclusion criteria:

• Non-free-living adults
• Adults <18 or >70 years at recruitment
• BMI<18
• Current smokers

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Active Comparator: Western diet	Western diet	Diet Rich in Processed Foods (48% carbohydrates, 10.4% fibres; 14% proteins and 39% fats).
Experimental: Plant-based diet	Plant-based diet	Diet rich in fruit and vegetables (42% carbohydrates, 17.2% fibres; 15% proteins and 43% fats).

Primary Outcome Measures

Name	Time	Method
Gut microbiota changes	Change over 14 days	Significant changes in the number of bifidobacteria
Quantification of Trimethylamine N-oxide	Day 16	Changes in response to L-Carnitine challenge

Secondary Outcome Measures

Name	Time	Method
Bioactivity of faecal water	Change over 14 days	Measured by using faecal water as basis for growth media (ex vivo measure)
Effects on inflammatory markers of both diets	Change over 14 days	Cytokine analysis via ELISA test (MagPix)
Ex vivo effects of faecal water on gut pathobionts	Day 14	Co-culturing the aqueous phase of faeces with C. difficile to assess changes in its biology
Quantification of phytochemicals	Change over 14 days	Measured by LC-MS
Quantification of Short Chain Fatty Acids (SCFA)	Change over 14 days	Measured by nuclear magnetic resonance (NMR)

Trial Locations

Locations (1)

Human Intervention Studies Unit, Ulster University; 🇬🇧 Coleraine, Londonderry, United Kingdom