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Status unknownNCT05071196Updated Apr 1, 2022

Facilitated Vegan Diet on Cardiometabolic Endpoints and Trimethylamine N-oxide

An interventional study of Facilitated Vegan Diet and Omnivorous Diet in Cardiometabolic Risk Factors, sponsored by David Grant U.S. Air Force Medical Center. Status unknown at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-04-01.

Sponsored by David Grant U.S. Air Force Medical Center · Not applicable, Interventional, and Prevention

The sponsor has not verified this record recently (last verified Mar 2022), so the status shown — last known as Active, not recruiting — may be out of date.
Phase
Not applicable
Study type
Interventional
Enrollment
70
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

Vegan meal kit delivery offers consumer convenience and has shown benefit in cardiometabolic parameters such as low-density lipoprotein cholesterol (LDL-c) and weight. The purpose of this study is to evaluate the impact of meal kit facilitated vegan diet on LDL-c and trimethylamine N-oxide (TMAO) when compared to an omnivorous diet control.

Read the detailed description

This study will compare the impact of a vegan diet to a non-vegan diet, when provided with meal kits in participants who are overweight.

A vegan diet includes foods that come from plants and excludes foods that come from animals like meat, dairy, and eggs. Dietary modifications such as adopting a vegan diet are associated with significant improvements in cardiometabolic parameters, making it one of the preferred treatment options for obesity and preventing associated health conditions. Meal kits are packages that include: a quick (\~30-45 minutes) and simple recipe, all the recipe's required ingredients, and are conveniently delivered to patient homes. In this study, a facilitated vegan diet is defined as a change from an omnivorous diet to a vegan diet with the aid of boxed vegan meal kit delivery. A facilitated vegan diet has shown LDL-c and weight improvements over continuing an omnivorous diet in a preliminary study.

TMAO, changes in gut microbiome, and compliance to dietary modification impact cardiovascular and overall health. TMAO is a diet dependent biomarker for CVD, as elevated TMAO levels are associated with a 62% increased risk of heart attack, stroke, or death. TMAO increases platelet hyperactivity, inflammation, and foam cell generation, all of which contribute to atherosclerosis and may explain the increased risk of CVD. Additionally, TMAO predicts risk of major adverse cardiovascular events independently of other cardiovascular risk factors.

Consumption of animal products elevate TMAO levels due to its abundance of TMAO precursors: choline and carnitine. Chronic dietary red meat was associated with increased TMAO levels over white meat and non-meat protein. One study found that consuming plant-based alternative meat products improved TMAO levels over a mostly red meat diet. Both study interventions replaced protein sources but did not remove animal products such as eggs and dairy, which have conflicting evidence relative to TMAO. This study intervention will have participants adopt a full vegan diet, eliminating animal products.

The gut microbiome plays a crucial role in converting dietary precursors into TMAO. TMAO levels post l-carnitine ingestion were significantly higher in patients on a long-term omnivorous diet vs patients on a long-term vegan or vegetarian diet. This suggests that the gut microbiome in a plant-based diet lowers the formation of TMAO via the diet. This study will explore changes in gut microbiome from a dietary intervention in relation to TMAO and explore if these changes are sustained after discontinuing a 4-week facilitated vegan diet. Additionally, changes in gut microbiome will be explored in relation to microbiota changes seen in other disease states such as anxiety, irritable bowel disease, and other inflammatory diseases.

The impact of dietary modifications on controlling obesity and associated health conditions has room for improvement. Dietary modifications have long been one of the preferred treatments in obesity and CVD prevention, yet the obesity rates continue to rise. One potential area of improvement is compliance to dietary modification. This study will explore changes in food group restricted free diet patterns after a 4-week vegan meal kit intervention.

02

Conditions studied

  • Cardiometabolic Risk Factors

Keywords

  • Vegan
  • boxed meal kit
  • trimethylamine N-oxide
  • cardiometabolic
03

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes

Inclusion criteria

  • Age ≥ 18 years old
  • BMI ≥ 25kg/m\^2
  • Consume ≥ 5 servings red meat per week
  • Active duty military and Department of Defense (DoD) Beneficiaries with active Tricare insurance
  • Willing and able to adopt a vegan or standard omnivorous diet for 4 weeks
  • Willing and able to track meal patterns, nutritional intake, exercise activity, and adverse events for 13 weeks
  • Willing and able to come to David Grant USAF Medical Center for 4 blood draws
  • Able to receive weekly emails and receive and prepare meal kits

Exclusion criteria

Exclusion Criteria:

  • Currently on a vegetarian, vegan, or food-group restricted diet
  • Currently taking or planning to initiate medications or supplements that significantly affect TMAO levels, carnitine, choline, or gut microbiome (Systemic antibiotics, antifungals, antivirals, antiparasitic, corticosteroids, methotrexate, cytokines, or immunosuppressive cytotoxic agents, laxatives, proton pump inhibitors, resveratrol, meldonium, or metformin)
  • Currently consuming the following ≥ 2 times per week: probiotics/prebiotics, probiotic enhanced foods (eg. enhanced yogurt, kefir, kombucha), or energy drinks, multivitamins, or supplements with choline, carnitine, or betaine (Acceptable to consume: non-probiotic enhanced yogurts, energy drinks and multivitamins without choline, carnitine, or betaine)
  • Participants will have the option to delay study start if they express interest in the study and have permanently discontinued one of the excluded diet, medication, or supplement listed previously within the past 4 weeks (minimum 4 week time between discontinuation of excluded item and study start)
  • Clinically significant or unstable cardiovascular, gastrointestinal, hepatic, or renal disease states defined as requiring on-going changes to medication or medical management
  • Consumption of smoking or chewing tobacco, or other nicotine-containing products for >1 day per week
  • Consumption of >14 alcohol drinks per week
  • Pregnant, breastfeeding, or plan to become pregnant
04

Study design

Phase
Not applicable
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
70 participants (estimated)

Study arms

  • Experimental
    Facilitated Vegan Diet

    The facilitated vegan participants will self-prepare and consume 2 vegan meal kits per day for 4 weeks

    Other: Facilitated Vegan Diet

  • Active comparator
    Standard Omnivorous Diet

    The standard omnivorous arm will self-prepare and consume 2 non-vegan meal kits per day for 4 weeks

    Other: Omnivorous Diet

Interventions

  • OtherFacilitated Vegan Diet

    Vegan boxed meal kits

  • OtherOmnivorous Diet

    Non-vegan boxed meal kits

05

What researchers measure

Primary outcomes

  1. Change between intervention arms in baseline adjusted LDL-c at 4 weeks

    Change in LDL-c

    Time frame: 4 weeks

  2. Change between intervention arms in baseline adjusted TMAO at 4 weeks

    Change in TMAO

    Time frame: 4 weeks

Secondary outcomes

  1. Change between intervention arms in baseline adjusted LDL-c at 8 weeks

    Change in LDL-c

    Time frame: 8 weeks

  2. Change between intervention arms in baseline adjusted LDL-c at 12 weeks

    Change in LDL-c

    Time frame: 12 weeks

  3. Change between intervention arms in baseline adjusted TMAO at 8 weeks

    Change in TMAO

    Time frame: 8 weeks

  4. Change between intervention arms in baseline adjusted TMAO at 12 weeks

    Change in TMAO

    Time frame: 12 weeks

  5. Change between intervention arms in baseline adjusted lipid panel parameters at 4 weeks

    Change in lipid panel

    Time frame: 4 weeks

  6. Change between intervention arms in baseline adjusted lipid panel parameters at 8 weeks

    Change in lipid panel

    Time frame: 8 weeks

  7. Change between intervention arms in baseline adjusted lipid panel parameters at 12 weeks

    Change in lipid panel

    Time frame: 12 weeks

  8. Change between intervention arms in baseline adjusted BMI at 4 weeks

    Weight and height will be combined to report BMI in kg/m\^2

    Time frame: 4 weeks

  9. Change between intervention arms in baseline adjusted BMI at 8 weeks

    Weight and height will be combined to report BMI in kg/m\^2

    Time frame: 8 weeks

  10. Change between intervention arms in baseline adjusted BMI at 12 weeks

    Weight and height will be combined to report BMI in kg/m\^2

    Time frame: 12 weeks

  11. Change between intervention arms in baseline adjusted blood pressure at 4 weeks

    Measured with Sphygmocor device, both systolic and diastolic blood pressures

    Time frame: 4 weeks

  12. Change between intervention arms in baseline adjusted blood pressure at 8 weeks

    Measured with Sphygmocor device, both systolic and diastolic blood pressures

    Time frame: 8 weeks

  13. Change between intervention arms in baseline adjusted blood pressure at 12 weeks

    Measured with Sphygmocor device, both systolic and diastolic blood pressures

    Time frame: 12 weeks

  14. Change between intervention arms in baseline adjusted hemoglobin A1c at 4 weeks

    Change in hemoglobin A1c

    Time frame: 4 weeks

  15. Change between intervention arms in baseline adjusted hemoglobin A1c at 8 weeks

    Change in hemoglobin A1c

    Time frame: 8 weeks

  16. Change between intervention arms in baseline adjusted hemoglobin A1c at 12 weeks

    Change in hemoglobin A1c

    Time frame: 12 weeks

Other outcomes

  1. Difference between intervention arms in baseline adjusted gut microbiome at 4 weeks

    Change in alpha diversity

    Time frame: 4 weeks

  2. Change between intervention arms in baseline adjusted gut microbiome at 8 weeks

    Change in alpha diversity

    Time frame: 8 weeks

  3. Change between intervention arms in baseline adjusted gut microbiome at 12 weeks

    Change in alpha diversity

    Time frame: 12 weeks

  4. Change between intervention arms in baseline adjusted complete blood count

    Change in complete blood count

    Time frame: 12 weeks

  5. Change between intervention arms in baseline adjusted serum C-reactive protein

    Change in C-reactive protein

    Time frame: 12 weeks

  6. Change between intervention arms in baseline adjusted serum high sensitivity C-reactive protein

    Change in high sensitivity C-reactive protein

    Time frame: 12 weeks

  7. Change between intervention arms in baseline adjusted serum vitamin B12 level

    Change in vitamin B12

    Time frame: 12 weeks

  8. Change between intervention arms in baseline adjusted serum iron

    Change in serum iron

    Time frame: 12 weeks

  9. Change in calorie intake

    Change in calorie intake

    Time frame: 12 weeks

  10. Change in meal patterns post vegan meal kit intervention

    Change in percent of vegan meals per week

    Time frame: 12 weeks

06

Study locations

1 site
  • David Grant U.S. Air Force Medical Center
    Travis Air Force Base, California 94535, United States
07

References and documents

Publications

  • The Vegan Diet. National Health Service website. Updated Aug 2018. Accessed 10 Jan 2021.
  • Najjar RS, Moore CE, Montgomery BD. A defined, plant-based diet utilized in an outpatient cardiovascular clinic effectively treats hypercholesterolemia and hypertension and reduces medications. Clin Cardiol. 2018 Mar;41(3):307-313. doi: 10.1002/clc.22863. Epub 2018 Mar 25. PubMed 29575002 ↗
  • Heianza Y, Ma W, Manson JE, Rexrode KM, Qi L. Gut Microbiota Metabolites and Risk of Major Adverse Cardiovascular Disease Events and Death: A Systematic Review and Meta-Analysis of Prospective Studies. J Am Heart Assoc. 2017 Jun 29;6(7):e004947. doi: 10.1161/JAHA.116.004947. PubMed 28663251 ↗
  • Tang WH, Wang Z, Levison BS, Koeth RA, Britt EB, Fu X, Wu Y, Hazen SL. Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk. N Engl J Med. 2013 Apr 25;368(17):1575-84. doi: 10.1056/NEJMoa1109400. PubMed 23614584 ↗
  • Wang Z, Bergeron N, Levison BS, Li XS, Chiu S, Jia X, Koeth RA, Li L, Wu Y, Tang WHW, Krauss RM, Hazen SL. Impact of chronic dietary red meat, white meat, or non-meat protein on trimethylamine N-oxide metabolism and renal excretion in healthy men and women. Eur Heart J. 2019 Feb 14;40(7):583-594. doi: 10.1093/eurheartj/ehy799. PubMed 30535398 ↗
  • Crimarco A, Springfield S, Petlura C, Streaty T, Cunanan K, Lee J, Fielding-Singh P, Carter MM, Topf MA, Wastyk HC, Sonnenburg ED, Sonnenburg JL, Gardner CD. A randomized crossover trial on the effect of plant-based compared with animal-based meat on trimethylamine-N-oxide and cardiovascular disease risk factors in generally healthy adults: Study With Appetizing Plantfood-Meat Eating Alternative Trial (SWAP-MEAT). Am J Clin Nutr. 2020 Nov 11;112(5):1188-1199. doi: 10.1093/ajcn/nqaa203. PubMed 32780794 ↗
  • Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nat Med. 2013 May;19(5):576-85. doi: 10.1038/nm.3145. Epub 2013 Apr 7. PubMed 23563705 ↗

Individual participant data

Plan to share: No

08

Registry details

Key details

Study ID
NCT05071196
Lead sponsor
David Grant U.S. Air Force Medical Center
Responsible party
Kevin Pham (Principal Investigator, David Grant U.S. Air Force Medical Center) — Principal investigator
First posted
Oct 8, 2021
Start date
Jan 1, 2022
Primary completion
Jun 1, 2022 (estimated)
Completion
Jun 1, 2022 (estimated)
Last update
Apr 1, 2022

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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