Plain English Summary
Background and study aims
Fasting is an emerging practice as a preventive method. The media coverage of this nutritional method is increasing in Switzerland. The CIBE (Interlude Bien-être Center [www.interludebienetre.ch]) offers one week fast paid stays. The preventive properties of fasting are supported by preclinical data and scattered clinical trials. Preclinical research on fasting and caloric restriction suggests a beneficial effect on health. These benefits translate into increased longevity and decreased risk of heart disease and cancer. The aim of this study is to find out whether there is a persistence of metabolic effects after 2 months in non-diabetic people who are fasting for a week at CIBE.
Who can participate?
Clients at the Interlude Bien-être Center (Val d’Illiez, Valais, Switzerland) who voluntarily fast for a week
What does the study involve?
During the study, physical measurements (body composition, abdominal circumference, blood pressure, body temperature, body mass index, heart rate) and, for a selected group (more at risk of metabolic syndrome according to the measurements of abdominal circumference, body mass index, blood pressure), laboratory tests (lipid profile, blood glucose, protein C reactive, IGF-1) are carried out. These values are recorded at the beginning and end of the fast, and two months after the start of the fast. Forms on eating habits and physical activity are completed before fasting and two months later.
What are the possible benefits and risks of participating?
The participants thanks to these tests benefit from a screening (e. g. blood pressure, lipid profile, variation of body composition). Furthermore, they should return to the Center Interlude Bien-être two months after fasting. The greatest risk is related to blood sampling which causes an injury to the elbow crook, which can bleed, cause an ecchymosis (discoloration), a hematoma (swelling) and, rarely, become complicated by infection and thrombosis.
Where is the study run from?
Centre Interlude Bien-Être (Switzerland)
When is the study starting and how long is it expected to run for?
April 2018 to June 2021
Who is funding the study?
The study is partially funded by the company Interlude Bien-être Sarl. Research and statistical analysis costs are borne by researchers (Mauro Frigeri, MD; Valeria Galetti, PhD; Marica Brnic Bontognali, PhD)
Who is the main contact?
Dr Mauro Frigeri
Fondazione Hospice Ticino
viale dei Faggi 8
+41 (0)79 174 53 27
Observational study on metabolic effects for clients who fast for one week at the Centre Interlude Bien-être, two months after the onset of fasting: body composition and plasma LDL cholesterol concentration
The voluntary realisation of a week-long fast has objective metabolic effects that persist at two months from the beginning of the fast.
Approved 24/04/2019, Commission cantonale d’éthique de la recherche sur l’être humain du canton de Vaud (avenue de Chailly 23, 1012 Lausanne, Switzerland; +41 21 316 18 30; firstname.lastname@example.org), ref: 2019-00415
Observational cohort study lasting 2 years
Primary study design
Secondary study design
Patient information sheet
Clients of the Centre Interlude Bien-être, where a week of fasting is done voluntarily
Study participants are recruited from clients at the Interlude Bien-être Center (Val d’Illiez, Valais, Switzerland) who voluntarily fast for a week. Body composition, blood pressure (TA), body mass index (BMI), abdominal circumference (CA), temperature, heart rate and, in a group selected (BMI ≥ 30kg/m2, or TA ≥ 130/85mmHg or antihypertensive drug, or CA ≥ 80cm in women and ≥ 94cm in men) for blood sampling, blood glucose, lipid profile, insulin-like growth factor 1 (IGF-1), C-reactive protein (CRP) are compared between before fasting, after fasting and at two months from the beginning of fasting. Forms describing diet and physical activity are completed before fasting and two months after the start of fasting.
Primary outcome measure
Plasma LDL cholesterol (laboratory analysis in mmol/l) measured at the onset of fasting and two months after the beginning of the fasting week, in the group selected for blood sampling
Secondary outcome measures
1. Total cholesterol (mmol/l), HDL cholesterol (mmol/l), triglycerides (mmol/l), blood glucose (mmol/l), CRP (mg/l) and IGF-1 (ng/ml), in the group selected for blood sampling (laboratory analysis), and variation in BMI (kg/m2), CA (cm), TA (mmHg), heart rate (/min), temperature (°C), measured at the beginning of the fast and 2 months after
2. The same measures (and LDL cholesterol) at the beginning and at the end of the fast
3. Fat-free mass measured by bioelectrical impedance analysis at 50 kHz with Nutrigard MS performed at the beginning, end and 2 months after the beginning of the fast
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Informed consent
2. Participating in a fasting week at the Centre Interlude Bien-être
3. Age ≥ 20 years, ≤ 70 years
Target number of participants
100 (20 included in the group selected for the blood test)
Participant exclusion criteria
1. Diabetes mellitus or taking glucose-lowering medication
2. BMI <18kg/m2
3. Known eating disorders (orthorexia, anorexia, bulimia)
4. Known metabolic pathologies that contraindicate fasting (e.g. deficiencies gluconeogenesis)
5. Pregnant women or during the lactation period
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Centre Interlude Bien-Être
Fondazione Hospice Ticino
Groupe pour l'étude du jeûne (Mauro Frigeri
MD; Valeria Galetti
PhD; Marica Brnic Bontognali
c/o Mauro Frigeri
viale dei Faggi 8
Interlude Bien-être Sarl
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer-reviewed journal.
IPD sharing statement
The data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
Participant level data
To be made available at a later date
Basic results (scientific)