The Effects of an 8-week Vegan Diet on TMAO Levels and Post-challenge Glucose Levels in Individuals With Dysglycaemia

NCT03315988 | Completed

• 1 other identifier: 0625
• Study Type: interventional
• Target: 28
• Locations: 1 country
• Sites: 1

Brief Summary

The amount of people with diabetes mellitus has now reached over 4 million in the United Kingdom. Type 2 diabetes accounts for the majority of all cases of diabetes and increases the risk of many other diseases such as heart problems. Plant based diets are thought to be an effective way to improve markers of health related to type 2 diabetes and heart disease. One way that a plant based diet improves health could be through reducing waste products that are generated in the gut by the bacteria that break down food as part of the digestion process. For example, the digestion of some meats, fish and eggs results in the creation of a substance called Trimethylamine-N-Oxide (TMAO) which has been linked to worse health outcomes in several studies. However, the full impact on TMAO and blood glucose levels of swapping regular meat consumption for a plant based vegan diet is not fully understood and requires further research. Therefore, the aim of this study will be to develop and undertake a clinical trial to investigate the effects of an 8-week vegan diet on TMAO levels and post challenge glucose levels in individuals with dysglycaemia (drug naïve). The study will be interventional single group prospective trial of adults aged 18-75 years of age from a multi-ethnic population with dysglycaemia (drug naïve). A sample of 29 people will be sought. The dietary intervention (vegan diet) will last 8 weeks. Then, the participants will go back to their normal diet and come for their final visit after a four week follow-up period (week 12). To assess the effectiveness of the intervention, primary and secondary outcome data collected at baseline will be compared with data collected at 1 week, 8 weeks and 12 weeks.

Conditions

Diabetes Mellitus, Type 2; Heart Diseases

Keywords

type 2 diabetes; vegan diet; TMAO; cardiovascular disease

Outcome Measures

Primary Outcomes (2)

• Change from Baseline TMAO plasma levels at 1, 8 and 12 weeks.

  urine and plasma samples for TMAO (μM)

  at 1 (+ 5 days) week , 8 (+/- 5 days) weeks and 12 weeks (+/- 5 days)

• Change from Baseline 3-hour post-challenge glucose levels at 1, 8 and 12 weeks.

  blood samples (mmol/l)

  at 1 (+ 5 days) week , 8 (+/- 5 days) weeks and 12 weeks (+/- 5 days)

Secondary Outcomes (24)

• TMAO (μM) urine levels at baseline.

  at baseline

• Change from Baseline in TMAO urine/plasma levels at 1 week following a vegan diet.

  at 1 week (+ 5 days)

• Change from Baseline 3-hour post-challenge glucose levels at 1 week following a vegan diet.

  at 1 week (+ 5 days)

• Change from week 8 in TMAO urine/plasma levels at 4 weeks after diet has returned to normal (week 12).

  at 12 weeks (+/- 5 days)

• Change from week 8 in 3-hour post-challenge glucose levels at 4 weeks after diet has returned to normal (week 12).

  at 12 weeks (+/- 5 days)

Study Arms (1)

Vegan diet

EXPERIMENTAL

Intervention Description and Definition The participants will be asked to follow a diet that excludes foods hypothesised to support the syntheses of TMAO, particularly meat (any), eggs and fish (any). A number of studies suggest that dairy products may also have an effect in modulating TMAO production whereas other studies do not. Therefore, in order to avoid any potential contaminating or confounding effect, dairy products will also be avoided. The diet employed in this study is broadly aligned to a vegan diet. The term vegan will be used to aid behaviour change and food choice. For example, an increasing array of products are now pack marked as vegan. The participants will be asked to keep their diet similar to their original and the Registered Dietitian involved in this study will plan their weekly menus accordingly.

Other: Adoption of a vegan diet

Interventions

Adoption of a vegan diet OTHER

Adoption of a vegan diet The participants of this study wil be asked to adopt a vegan diet under the supervision of a Registered Dietitian.

Vegan diet

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participant is willing and able to give informed consent for participation in the study
• And either:
• Overweight (White: BMI\>25 - \<30, South Asian/ Black and minority ethnic group \<27.5) with HbA1c between HbA1c ≥5.7% and ≤ 8% (39-64 mmol/mol) identified within the last 36 months
• Obese: (White: BMI ≥30, South Asian/ Black and minority ethnic group: ≥27.5)
• Male or Female
• Aged 18 - 75 years inclusive
• Able to understand, read and speak the English language to a sufficient level to understand and take part to the study in the investigators opinion
• Have access to a phone, and willing to use it as part of the study
• Regular meat and/or fish eater (at least 3 times per week)-self reported

You may not qualify if:

• Participant is unwilling or unable to give informed consent
• Non-English speakers
• HbA1c above 8% (64 mmol/mol)
• Taking any form of glucose lowering medication currently or within the last 60 days
• Current smokers
• Current use of vegan or vegetarian diet
• Recent significant weight change (10% or more) over the last 3 months
• Pregnancy/lactation
• Clinical eating disorder as detected by their GP or relevant health professional (e.g. dietitian)
• Have a terminal illness
• Current or recent (within 6 months) oral antibiotics or steroid use as their usage could impact on the gut bacteria profile
• Ongoing CVD (e.g. angina) \*

Sponsors & Collaborators

• University of Leicester: lead
• University Hospitals, Leicester: collaborator

Study Sites (1)

Leicester Diabetes Centre

Leicester, LE3 4PW, United Kingdom

Location

Related Publications (1)

• Argyridou S, Davies MJ, Biddle GJH, Bernieh D, Suzuki T, Dawkins NP, Rowlands AV, Khunti K, Smith AC, Yates T. Evaluation of an 8-Week Vegan Diet on Plasma Trimethylamine-N-Oxide and Postchallenge Glucose in Adults with Dysglycemia or Obesity. J Nutr. 2021 Jul 1;151(7):1844-1853. doi: 10.1093/jn/nxab046.

  PMID: 33784394 DERIVED

MeSH Terms

Conditions

Diabetes Mellitus, Type 2; Heart Diseases; Cardiovascular Diseases

Condition Hierarchy (Ancestors)

Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 4, 2017
• First Posted: October 20, 2017
• Study Start: October 4, 2017
• Primary Completion: January 7, 2019
• Study Completion: January 7, 2019
• Last Updated: January 30, 2020

Record last verified: 2018-09

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)