The Link Between Diets and Health Indicators

Study Overview
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Brief Summary
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The cohort study investigates the effect of different dietary intake among omnivorous, vegan, vegetarian and low-carb diets on health parameters and on long-term overall health. The participants blood parameters, dietary intake, gut microbiota composition, body mass and composition, resting energy expenditure, lifestyle factors and psychological factors will be determined and measured.

Detailed Description
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Vegetarian and vegan diets have been shown to have health benefits on preventing cardiovascular diseases, type 2 diabetes and cancer. They are both gaining popularity in public. Ketogenic diet has also been very popular, especially due to its effect on weight loss and blood glucose parameters. To our knowledge there, are no studies that compare long-term effects of all three diets and omnivorous diets with regards to health parameters and gut microbiota composition. The aim of the proposed study is to investigate the link between different diets and health parameters, such as parameters related to longevity, inflammation, stress and gut microbiota composition. The study is designed to compare different diets and their relationship with the body as a whole.

Official Title
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The Link Between Omnivorous, Vegan, Vegetarian, Low Carb Diets and Health Indicators in Healthy Subjects With Normal Weight

Conditions
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Healthy Diet, Microbiota

Intervention / Treatment
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* Behavioral: Regular lifestyle in different circumstances


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18,5 < BMI < 30 kg/m2 asymptomatic for any disease medication free same pattern of eating in the last 3 months stable body mass in the last 3 months Exclusion Criteria: BMI < 18,5 and > 30 kg/m2 presence of any chronic disease taking any medications changed eating pattern in the last 3 months unstable body mass in the last 3 months taking antibiotics in the last 3 months

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| omnivors<br>Participants who habitually consume all food groups in their diet. | Behavioral: Regular lifestyle in different circumstances<br>* Participants' lifestyle will be followed over the years.<br>|
| vegetarian<br>Participants who habitually avoid meat in their diet. | Behavioral: Regular lifestyle in different circumstances<br>* Participants' lifestyle will be followed over the years.<br>|
| vegan<br>Participants who habitually avoid all animal source food in their diet. | Behavioral: Regular lifestyle in different circumstances<br>* Participants' lifestyle will be followed over the years.<br>|
| low-carbohydrate high-fat diet<br>Participants who habitually avoid carbohydrate in their diet. | Behavioral: Regular lifestyle in different circumstances<br>* Participants' lifestyle will be followed over the years.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in systemic inflammation | CRP [mg/L] will be measured as a marker of inflammation. | Change from baseline at 5 years. | 
| Changes in serum total antioxidative capacity | Total antioxidative capacity of serum will be measured with Photochem instrument and expressed as nanomole equivalents of ascorbic acid per microliter of serum. | Change from baseline at 5 years. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in macronutrient intake | Macronutrient intake will be measured with validated FFQ and 3-day food diary and analysed with softwares OPEN and Prodi. Macronutrient intake will be expressed as part of daily energy intake. | Change from baseline at 5 years. | 
| Changes in micronutrient intake | Micronutrient intake will be measured with validated FFQ and 3-day food diary and analysed with softwares OPEN and Prodi. Micronutrient intake will be expressed as mg per day. | Change from baseline at 5 years. | 
| Changes in gut microbiota composition | Microbial composition of stool will be determined with microbial DNA isolation and identification. | Change from baseline at 5 years. | 
| Changes in body composition | Fat free body mass will be measured with bioelectrical impedance analysis and expressed in kg. | Change from baseline at 5 years. | 
| Changes in resting metabolic rate | Resting metabolic rate will be determined with indirect calorimeter and expressed in kJ/day. | Change from baseline at 5 years. | 
| Changes in lifestyle factors | Will be assessed with a questionnaire. | Change from baseline at 5 years. | 
| Changes in anxiety | Will be assessed by state-trait anxiety inventory. The STAIX-1 contains 20 items, which are scored on a 4-pointscale with subscale scores ranging from 20 to 80, with higherscores indicating higher anxiety. | Change from baseline at 5 years. | 
| Changes in body satisfaction | Will be assessed by the body dissatisfaction subscale from the Eating Disorders Inventory-2. Responses will be rated on a 5-point Likert scale from 0 (never) to 4 (always). | Change from baseline at 5 years. | 
| Changes in grip strength | Will be measured with a hand dynamometer. | Change from baseline at 5 years. | 
| Changes in autophagy | Autophagy will be measured by autophagy-related mRNA gene expression evaluation. | Change from baseline at 5 years. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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diet, gut microbiota, longevity, inflammation, health