An interventional study of Five-day hypocaloric and ketogenic programme in Healthy Nutrition and Healthy Lifestyle, sponsored by Buchinger Wilhelmi Development & Holding GmbH. Completed at 1 site in Germany. Open to participants aged 18 Years to 80 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-10-01.
Sponsored by Buchinger Wilhelmi Development & Holding GmbH · Not applicable, Interventional, and Prevention
The aim of this study is to assess changes in body and metabolism caused by this new five-day hypocaloric and ketogenic programme
Therapeutic effects of fasting are increasingly documented. Recent studies on a cohort of subjects doing a long-term fasting lasting from 4 days to several weeks demonstrated beneficial effects on health and well-being. In recent studies on the therapeutic efficacy of the Buchinger Wilhelmi fasting program, long-term fasting significantly improved risk factors for a variety of chronic diseases including hypertension even in medicated subjects, liver steatosis, inflammation, oxidative stress and lipoprotein distribution.
There is an increasing demand for dietary interventions which can be delivered at home. This has been amplified by the Coronavirus-19 disease (COVID-19) pandemic during which many countries kept their population in lockdown at home in isolation. The COVID-19 pandemic has also influenced the lifestyle of individuals, with an increased consumption of unhealthy food and a sedentary behaviour resulting in mental (anxiety, depression, and others) and physical (weight gain, rise in blood pressure) health issues. In order to adapt to this new context, the Buchinger Wilhelmi Clinics have created a hypocaloric, ketogenic program with interval fasting.
The five-day programme is designed to be easily integrated into everyday life and can be applied several times a year. The programme is based on ready-to-eat soups made with locally sourced organic ingredients. The ingredients represent a total daily intake of around 600 kcal per day - with a high share of fats and a limited quantity of carbohydrates and proteins. Minerals and micronutrients used at the Buchinger Wilhelmi Clinics are also supplied. Although the comprehensive medical care and assistance offered at the clinics cannot be replicated, medical professionals are available to support the customers remotely.
The investigators hypothesise that the metabolic changes caused by this new five-day programme can be similar to a short-term fast. In order to test this hypothesis, the investigators will perform a two-arm randomized controlled trial in which a group of participants will perform the five-day Fastingbox programme and a group of participants will receive an eucaloric diet as a control group.
Buchinger Wilhelmi Development & Holding GmbH is the lead sponsor of 5 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The group will receive a five-day remotely delivered hypocaloric and ketogenic programme followed by a four-day food reintroduction period
Other: Five-day hypocaloric and ketogenic programme
The group will maintain their habitual diet
Dietary intervention
Also known as: Buchinger Wilhelmi Fastingbox
Changes in body weight
in kg
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in systolic blood pressure
in mmHg
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in diastolic blood pressure
in mmHg
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in acetoacetic acid
measured by nitroprussid test in urine in mg/dL
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in total cholesterol
measured in serum by a routine technique (photometry)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in HDL-C
measured in serum by a routine technique (elimination/catalase)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in LDL-C
measured in serum by a routine technique (elimination/catalase)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in triglycerides
measured in serum by a routine technique (GPO, trinder without serum blank) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in glucose
measured in serum by a routine technique (hexokinase) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in HbA1c
measured in serum by a routine technique (HPLC) in %
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in Insulin
measured in serum by a routine technique (CLIA) in mU/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in total antioxidant capacity
measured in serum by a routine technique
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in lipidperoxidation
measured in serum by a routine technique (in µmol/l)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in well-being
WHO-5 well-being index
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in ESR
measured in mm/h by kinetic flow analysis in capillaries on a photometric basis
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in CRP
measured in serum by a routine technique
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in IL-6
measured in serum by a routine technique (ECLIA)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in IL-10
measured in serum by a routine technique
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in TNF-a
measured in serum by a routine technique (CLIA)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in gut microbiome composition
Shotgun metagenomics, qPCR, SCFA
Time frame: At baseline, first stool after 9 days as well as 1 month afterwards
Changes in body mass index
in kg/m²
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in abdominal circumference
in cm
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in resting heart frequency
in beats/min
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in leucocytes
measured in serum by a routine technique (electronic count)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in erythrocytes
measured in serum by a routine technique (electronic count)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in haemoglobin
measured in serum by a routine technique (photometry)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in haematocrit
measured in serum by a routine technique (electronic count)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in MCV
measured in serum by a routine technique (ELISA)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in MCH
measured in serum by a routine technique
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in MCHC
measured in serum by a routine technique
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in thrombocytes
measured in serum by a routine technique (electronic count)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in INR
measured in serum by a routine technique (coagulometry) in sec
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in PTT
measured in serum by a routine technique (coagulometry) in sec
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in kidney parameters
blood parameters: uric acid, urea, creatinine in mg/dl
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in uric acid
measured in serum by a routine technique (enzymatic/uricase/peroxidas) in mg/dl
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in urea
measured in serum by a routine technique (GLDH) in mg/dl
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in creatinine
measured in serum by a routine technique (creatininase) in mg/dl
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in GOT
measured in serum by a routine technique (IFCC method) in U/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in GPT
measured in serum by a routine technique (IFCC method) in U/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in GGT
measured in serum by a routine technique (IFCC modified) in U/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in AP
measured in serum by a routine technique in U/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in sodium
measured in serum by a routine technique (potentiometric, ISE) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in potassium
measured in serum by a routine technique (potentiometric, ISE) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in calcium
measured in serum by a routine technique (CPC) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in magnesium
measured in serum by a routine technique (ICPMS) in mmol/l
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in continous glucose monitoring
glucose level in mg/dl
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in physical activity level
questionnaires: International Physical Activity Questionnaire (IPAQ) 150min./week of exercise is considered sufficient physical activity
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in sleep quality
questionnaires: Pittsburgh Sleep Quality Index (PSQI), score ranging from 0 to 21, where lower scores denote a healthier sleep quality
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in processed food consumption
questionnaire: highly processed food consumption (sQ-HPF)
Time frame: At baseline, after 5 and 9 days as well as 1 month afterwards
Changes in physical well-being
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in emotional well-being
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in energy level
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in cravings
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in feeling bloated
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in feeling cold
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in tiredness
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in muscle weakness
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in back pain
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in headache
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in hunger
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in anxiety
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards9
Changes in digestive problems
measured by visual scale (0-10)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in optimism
measured by visual scale (0-4)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in relaxation
measured by visual scale (0-4)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in clear thinking
measured by visual scale (0-4)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in confidence
measured by visual scale (0-4)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in happiness
measured by visual scale (0-4)
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Changes in physical activity
measured by visual scale (0-10) and absolut numbers
Time frame: through study completion (11 subsequent days as well as one month afterwards)
Ethnicity
Caucasian, Hispanic, African American, Asian, others
Time frame: baseline
Smoking
status: never, former, current, flatmate
Time frame: baseline
Alcohol consumption
number of glasses: wine, beer, spirits
Time frame: baseline, after 5 and 9 days as well as 1 month afterwards
Changes in stress level
measured by visual scale (0-10)
Time frame: baseline, after 5 and 9 days as well as 1 month afterwards
Changes in energy level
measured by visual scale (0-10)
Time frame: baseline, after 5 and 9 days as well as 1 month afterwards
Changes in pain level
measured by visual scale (0-10)
Time frame: baseline, after 5 and 9 days as well as 1 month afterwards
Plan to share: Undecided
Ran from Apr 2023 to primary completion in Aug 2023, 4 months.
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This study is completed, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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Buchinger Wilhelmi Development & Holding GmbH