Differences in Eating Frequency Between Vegan and Omnivorous Diets

Study Overview
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Brief Summary
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This study will pilot test the use of two mHealth devices. One is called the Bite Counter and one is called a MisFit. The study will be among a sample of participants (n = 50) to monitor their eating and sleeping habits. The Bite Counter is a wearable watch-like device that detects and records when an individual has taken a bite of food. The benefit of using the Bite Counter is that it places a low-burden on participants to self-monitor their dietary intake. The MisFit is a commercial device that tracks an individual's sleeping and activity. The purpose of this study is to (1) find out how the Bite Counter calculates daily bites taken on a vegan diet compared to an omnivorous diet, (2) examine differences in sleep and activity between individuals following a vegan diet compared to an omnivorous diet and (3) get feedback from users before the device is tested in larger studies.

Detailed Description
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In several randomized controlled trials comparing vegan or vegetarian diets to omnivorous dietary approaches, significant weight loss has occurred in the absence of significantly different changes in reported energy intake between groups. This is different than what is seen in studies using traditional weight loss diets (reduced energy omnivorous diets), which demonstrate a greater reduction in energy intake corresponding to greater weight loss. In observational cohort studies, among Adventist Health Study-2 participants following five different diets, BMI was found to be lowest among vegans and highest among omnivores; yet energy intake did not significantly differ among the five groups, averaging 2,000 kcals/day, with the exception of lower energy intake among semi-vegetarians. This difference in body weight without observed differences in energy intake could possibly be explained by higher levels of physical activity among vegan and vegetarian participants, which have been observed in some of the cohort studies. Physical activity, however, was controlled for in the randomized trials either giving participants identical exercise recommendations, or holding exercise levels constant across experimental groups. This present study will utilize the Bite Counter to estimate the differences between calories consumed between a vegan diet and an omnivore diet. The significance of using the Bite Counter is that it is a simple way to estimate energy intake. While there are many devices that measure energy expenditure (e.g. various exercise scales and equipment), there are few devices that account for energy intake. Traditional methods of estimating energy intake tend to utilize dietary recalls, but these procedures require much more effort and do not provide real time feedback like the Bite Counter does. Therefore, this study will contribute to current research by capturing data on dietary differences between vegans and omnivores, as well as assessing the usability of this device for dietary self-monitoring. The study will also use an objective physical activity and sleep tracker (the MisFit) to examine differences in exercise and sleeping between omnivorous and vegan participants.

Official Title
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Differences in Eating Frequency Between Vegan and Omnivorous Diets

Conditions
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Eating Behavior

Intervention / Treatment
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* Behavioral: Vegan diet
* Behavioral: Follow habitual, usual diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participants must be adults (18 years and older) that are weight stable individuals (having a BMI between 18.5 - 25 Participants must have been following their chosen diet for at least the past 6 months Participants must be willing to wear a wrist-worn device to track their food intake and physical activity Exclusion Criteria: Participants should have not experienced weight loss or gain ±10 lbs over the past 6 months) and they must not be on a weight loss diet

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Vegan arm<br>A vegan diet is one that does not contain any animal products (no meat, fish, poultry, eggs, or dairy) but emphasizes plant-based foods, such as fruits, vegetables, whole grains, and legumes/beans. Researchers will ask participants on a vegan diet to follow their usual diet and exercise habits consistent for the two week study period. | Behavioral: Follow habitual, usual diet<br>* Participants will be asked to consume their habitual, usual diet.<br>|
| Experimental: Omnivorous arm<br>A diet containing all food groups. Researchers will ask participants on an omnivorous diet to follow habitual, usual diet and exercise habits for the first week. During the second week, participants will be asked to switch to a vegan diet for one week and to maintain their usual exercise habits. | Behavioral: Vegan diet<br>* Participants in the omnivorous arm will be asked to follow their normal diet for one week and then follow a vegan diet for one week.<br>Behavioral: Follow habitual, usual diet<br>* Participants will be asked to consume their habitual, usual diet.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Eating frequency (number of bites taken per day) | Number of bites per day will be tracked with a wearable Bite Counter | 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Energy (kcal) intake | Energy intake will be assessed with 24-hour dietary recalls | 2 weeks | 
| Physical activity (number of steps/day) | Number of steps per day will be assessed with a wrist-worn pedometer (MisFit). | 2 weeks | 
| Sleep (number of hours of sleep each night) | Number of hours of sleep per night will be assessed with a wrist-word sleep tracking device (MisFit). | 2 weeks | 
| Mood (Depression, Anxiety, and Stress Scale (DASS 21) | Stress, anxiety, and depression will be assessed with the Depression, Anxiety, and Stress Scale (DASS 21) | 2 weeks |