Development and Evaluation of a Web-based Diet Quality Screener for Vegans (VEGANScreener)

Study Overview
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Brief Summary
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The primary objective of this study is to assess the construct validity and criterion validity for associations of the VEGANScreener with nutrient intakes from reference methods and associations with biomarkers of dietary intake. The investigators hypothesize that the screener is a valid tool to assess diet quality in the vegan population. The study will assess construct validity by testing whether the measure relates as it should to other measures (e.g., age, gender, education, SES differences). The investigators will assess concurrent and predictive validity (types of criterion validity) by evaluating associations and agreement between 'gold standards', such as diet records, biomarkers, and multi-metabolite signatures of intake. The investigators will examine associations of vegan diet quality with biomarkers of nutritional status, biomarkers of disease, and anthropometric measures and hypothesize that a higher diet quality in vegans is associated with a more favourable profile among vegans, for example, a lower blood pressure. This study is part of the European VEGANScreener Consortium.

Official Title
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Development and Evaluation of a Web-based Diet Quality Screener for Vegans (VEGANScreener)

Conditions
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Healthy

Intervention / Treatment
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* Other: This is an observational study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Self-reported vegans (≥2 years on a vegan diet; vegan diet defined as not consuming any dietary animal products more often than once/month, honey excluded) Self-reported omnivores. Consuming on average daily (at least 5 times/week) meat/meat products. Age 18 to 65 years (1:1 ratio 18-35,99 and 36-65) Males and females (1:1 ratio) Exclusion Criteria: Self-identified pescatarians (excluding all meat, except for fish/seafood) and reductarians/flexitarians (intentionally reducing intake of animal-based products) History of a disease known to affect intermediary metabolism (e.g., any diabetes on treatment, i.e. medication or lifestyle recommendations, thyreopathies, cancer etc.) BMI>30 kg/m2 History of disease of intestinal integrity (i.e., inflammatory bowel disease, chronic pancreatitis, other malabsorption, etc.). Pregnant or breastfeeding females.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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 |
| --- | --- |
| Omnivorous<br>Participants following an omniviours diet | Other: This is an observational study<br>* This is an observational study<br>|
| Vegan<br>Participants following a vegan diet | Other: This is an observational study<br>* This is an observational study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Validity of the vegan screener | The validity will be assessed by calculating associations between the screener and reference method. | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dietary intake | Dietary intake will be assessed using a weighed food record | Baseline | 
| Food habits | Food habits will be assessed using a food frequency questionnaire | Baseline | 
| Vitamin D status | Vitamin D status will be measured from venous blood samples | Baseline | 
| Homocysteine status | Homocysteine will be measured from venous blood samples | Baseline | 
| holo-transcobalamin | holo-transcobalamin will be measured from venous blood samples | Baseline | 
| Methoylmalonic acid | Methoylmalonic acid will be measured from venous blood samples | Baseline | 
| Vitamin B2 status | Vitamin B2 will be measured from venous blood samples | Baseline | 
| Vitamin C status | Vitamin C will be measured from venous blood samples | Baseline | 
| Folic acid status | Folic acid will be measured from venous blood samples | Baseline | 
| Magnesium status | Magnesium status will be determined from venous blood samples | Baseline | 
| Zinc status | Zinc status will be determined from venous blood samples | Baseline | 
| Selenoprotein-P status | Selenoprotein-P status will be determined from venous blood samples | Baseline | 
| Ferritin concentration | Ferritin concentration will be determined from venous blood samples | Baseline | 
| Soluble transferrin receptor concentration | Soluble transferrin receptor will be determined from venous blood samples | Baseline | 
| Hemoglobin concentration | Hemoglobin will be determined from venous blood samples | Baseline | 
| Creatinine concentration | Creatinine will be determined from venous blood samples | Baseline | 
| Uric acid concentration | Uric acid will be determined from venous blood samples | Baseline | 
| Urea concentration | Urea will be determined from urine samples samples | Baseline | 
| Iodine concentration | Iodine status will be determined from urine samples samples | Baseline | 
| Potassium concentration | Potassium status will be determined from urine samples samples iodine, potassium, sodium, calcium, creatinine) | Baseline | 
| Sodium concentration | Sodium status will be determined from urine samples samples | Baseline | 
| Calcium concentration | Calcium status will be determined from urine samples samples i | Baseline | 
| Creatinine concentration | Creatinine will be determined from urine samples samples | Baseline | 
| C-reactive protein concentration | The inflammatory marker hsCRP will be determined from serum | Baseline | 
| Triglyceride concentration | Triglyceride concentration will be determine from venous blood samples | Baseline | 
| Free fatty acid concentration | Free fatty acid concentration will be determine from venous blood samples ( | Baseline | 
| Eicosapentanoic acid | Eicosapentanoic acid (in % of total FA) will be determine from venous blood samples | Baseline | 
| Docosahexanoic acid | Docosahexanoic acid (in % of total FA) will be determine from venous blood samples | Baseline | 
| LDL-cholesterol concentration | LDL-cholesterol concentration will be determine from venous blood samples | Baseline | 
| HDL-Cholesterol concentration | HDL-Cholesterol concentration will be determine from venous blood samples | Baseline | 
| Cholesterol concentration | Cholesterol concentration will be determine from venous blood samples | Baseline | 
| Glucose concentration | Glucose will be measured from venous blood samples | Baseline | 
| Well being questionnaire | Participants well being will be assessed using a questionnaire. The scale of each question ranges from 0 to 10, 10 representing the highest well being | Baseline | 
| VEGANScreener | The VEGANScreener assesses diet quality using 29 questions of frequency of consumption of different foods and food groups. | Baseline and day 2 | 
| Weight | Weight will be measured in kg | Baseline | 
| Height | Height will be measured in m | Baseline | 
| Waist circumference | Waist circumference will be measured in cm | Baseline | 
| Hip circumference | Hip circumference will be measured in cm | Baseline |