Effects of Fasting in the Bahá'í Faith

Study Overview
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Brief Summary
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The aim of the study is to find out the effects a specific religious fast (i.e. Bahá'í fast) has on certain metabolic parameters, hydration, psyche and circadian clock. In a follow-up questionnaire series in 2019 we want to additionally validate a specific questionnaire for Bahai fasting, which was developed in 2018.

Detailed Description
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Followers of the Bahá'í Faith worldwide follow a yearly fasting tradition, where they fast intermittently for nineteen days. The intermittent fast is defined as abstinence from any food, drink and smoking from sunrise until sunset. These nineteen days are always in March and so do not coincide with climatic extremes in any country worldwide. This makes this kind of fasting a good model to study the psychological and medical effects of intermittent fasting in humans.

Official Title
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Medical And Psychological Effects of Nineteen Days of Intermittent Religious Fasting for Followers of the Bahá'í Faith- an Observational Study

Conditions
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Health Behavior, Healthy

Intervention / Treatment
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* Other: Intermittent Fasting


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: member of the Bahá'í religious community, Age between 18-69 years, the study participant must be able to understand the instructions given to him by the study personnel, the performance of the religious fast is planned in 2018 (and for the validation of the questionnaire also in 2019) Exclusion Criteria: An interruption of the religious fast is planned for more than five days, pregnant and nursing women, severe internistic condition, eating disorders (anorexia nervosa, bulimia), terminal or severe disease with marked impairments in mobility and vitality, non-existence of email address and Internet Access (because of online questionnaires), severe psychiatric disorder, simultaneous participation in another Trial Exclusion Criteria for subsample (energy metabolism measurements and microdialysis) Body Mass Index <18,0 und >30,9 kg/m2, claustrophobia, clinically relevant haemostaseological conditions or medication, vegan diet, special diet out of medical reasons, current dieting for weight loss, weight loss of more than 2 kg in the month before the study commenced, postsurgical conditions, acute and chronic infections, known drug or alcohol abuse additional exclusion criteria for microdialysis (subsample of energy metabolism measurements): allergy to local anaesthetics

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 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

| Intervention/Treatment |
| --- |
|Other: Intermittent Fasting|Intermittent Fasting with abstinence from food and drink daily from sunrise to sunset for nineteen consecutive days in March 2018|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum Osmolarity | Measured in subsample of study participants (venous blood sample) osmol/l | 12 hours | 
| In 2019: Validation of new questionnaire | New questionnaire, developed in 2018, regarding Bahai fasting | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urine Osmolality | Measured in subsample of participants, in spontaneous Urine sample and 12h/24h Urine samples osmol/kg | 24 hours | 
| Acid-base balance | Measured in subsample of study participants (venous blood sample) Measured with Radiometer, Base excess (mmol/l) | 5 Minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hydration, Intermittent Fasting, Religious Fast, Bahá'í, Calorimetry, Microdialysis, circadian clock, circadian rhythm, spirituality, self-efficacy