Clinical trial NCT05297825: Twins Nutrition Study (TwiNS): Vegan vs. Omnivore
Official title: Twins Nutrition Study (TwiNS): Vegan vs. Omnivore
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Lipid Metabolism
Glucose Intolerance
Weight Change, Body
Microbiome
Inflammation
Immune Function
Keywords: Lipids
Glucose
Body weight
Microbiome
Inflammation
Immune function
Lead sponsor: Stanford University
Sponsor class: OTHER
First posted: 2022-03-28
Enrollment: 44
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: This study is designed to investigate the health impact of a vegan diet compared to a usual, omnivorous diet. The investigators plan to study these diets in twins, where one twin follows a vegan diet and the other twin follows an omnivorous diet, thus the investigators control for genetic differences that might impact the effect of the diet.

Detailed description: During this study, the investigators will evaluate the nutrient intake in both the vegan and the omnivorous diet. The investigators will also measure physiologic markers of health such as lipid levels, HbA1C, heart rate, and weight, and they will also look at the effect of the diets on the microbiota. In addition to measuring the effect of the diet, the investigators will monitor adherence to the diet, and survey participants on the ease/difficulty in following a vegan diet as well as their energy levels and sense of wellbeing. Thus, this study will help us better understand the health impact and feasibility of following a vegan diet. These results will be of much interest to the general public and the health care professionals.

Eligibility criteria: Inclusion Criteria:

* Age 18+
* 1/2 of a pair of twins that will both be participating
* Willing to consume a plant-based diet (vegetables, fruit, whole grains, legumes, etc.)
* Willing to consume meat/eggs (beef, pork/sausage, chicken, eggs) \>= 1 time a day
* Willing to consume dairy (milk, yogurt, cheese) \>= 1 time a day

Exclusion Criteria:

* Weight \< 110 lb
* BMI \>= 40
* LDL-C \> 190 mg/dL
* Systolic Blood Pressure \> 160 mmHg OR Diastolic blood pressure \> 90 mmHg
* Pregnant, lactating or planning to become pregnant during the course of the study.
* Use of any of the following drugs/supplements within the last 2 months:

  * systemic antibiotics, antifungals, antivirals or antiparasitics (intravenous, intramuscular, or oral);
  * corticosteroids (intravenous, intramuscular, oral, nasal or inhaled);
  * cytokines;
  * methotrexate or immunosuppressive cytotoxic agents.
* Chronic, clinically significant, or unstable (unresolved, requiring on-going changes to medical management or medication) pulmonary, cardiovascular, gastrointestinal, hepatic or renal functional abnormality, as determined by medical history, Type 1 diabetes, dialysis
* History of active cancer in the past 3 years except for squamous or basal cell carcinomas of the skin that have been medically managed by local excision
* Unstable dietary history as defined by major changes in diet during the previous month, where the subject has eliminated or significantly increased a major food group in the diet.
* Recent history of chronic excessive alcohol consumption defined as more than five 1.5-ounce servings of 80 proof distilled spirits, five 12-ounce servings of beer or five 5-ounce servings of wine per day; or \> 14 drinks/week.
* Any confirmed or suspected condition/state of immunosuppression or immunodeficiency (primary or acquired) including HIV infection, multiple sclerosis and Graves' disease.
* Surgery of the GI tract, with the exception of cholecystectomy and appendectomy, in the past five years. Any major bowel resection at any time.
* Regular/frequent use of smoking or chewing tobacco, e-cigarettes, cigars or other nicotine-containing products
* Regular use of prescription opiate pain medication

Primary outcomes:
measure: Difference in LDL cholesterol
timeFrame: Baseline and 8 weeks
Secondary outcomes:
measure: Difference in triglycerides
timeFrame: Baseline and 8 weeks
measure: Change in inflammatory markers
timeFrame: Baseline and 8 weeks
measure: Change in alpha diversity
timeFrame: Baseline and 8 weeks
Other outcomes:
Locations:
city: Stanford
country: United States
facility: Stanford University
state: California
Study officials:
affiliation: Stanford University
name: Christopher D Garnder, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Landry MJ, Ward CP, Cunanan KM, Durand LR, Perelman D, Robinson JL, Hennings T, Koh L, Dant C, Zeitlin A, Ebel ER, Sonnenburg ED, Sonnenburg JL, Gardner CD. Cardiometabolic Effects of Omnivorous vs Vegan Diets in Identical Twins: A Randomized Clinical Trial. JAMA Netw Open. 2023 Nov 1;6(11):e2344457. doi: 10.1001/jamanetworkopen.2023.44457.