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Long-term Fasting: Multi-system Adaptations in Humans

Not Applicable
Completed
Conditions
Fasting
Interventions
Other: Long-term fasting according to the Buchinger Wilhelmi fasting program
Registration Number
NCT05031598
Lead Sponsor
Buchinger Wilhelmi Development & Holding GmbH
Brief Summary

The aim of this trial is to investigate the effects of long-term fasting on size, mass, composition and function of metabolic active tissues in several organs that reexpand possibly rejuvenated after 1-4 months. Additionally, the lipid metabolism is investigated in depth.

Detailed Description

Fasting displays numerous positive effects on metabolism, health and aging. Surprisingly, few considerations are given to long-term fasting periods.

The metabolic switch from food-derived glucose to adipose tissue-derived fatty acids and ketones as primary cellular fuel is the key to fasting metabolism. Fasting has been shown to improve cardiovascular risk factors and gut microbiota in humans. It provokes profound changes in lipid metabolism. However, many questions are still open concerning the mobilization, exchange, and function of lipids during long-term fasting. Furthermore, recent results show the ability of periodic restrictive nutritional strategies to trigger organ regeneration. This promising regenerative power has not been investigated comprehensively in humans. In addition, the knowledge about the role of human faecal microbiota in health and disease is increasing. Only little is known about its composition and function during fasting. We found indications that the gut microbiome could influence energy metabolism and consequently could influence the dynamic of the metabolic switch.

Long-term fasting under medical supervision according to the Buchinger Wilhelmi fasting program has been demonstrated to be safe and well-tolerated.

The current project investigates the effects of a 9±3 days fasting period by a multi-systemic approach focusing on lipid metabolism and the gut microbiome in 100 subjects. Additionally, the body composition in combination with muscle performance will be analyzed in-depth in a subgroup of 32 subjects.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
62
Inclusion Criteria
  • BMI between 22 - 35 kg/m2
Exclusion Criteria
  • intake of medication (cardiovascular diseases, lipid and glucose metabolism)
  • chronic manifest psychical and psychiatric diseases
  • participation in another study
  • pregnancy or breastfeeding
  • in the MRI/MRS sub-study, any MRI contraindication (claustrophobia, pacemakers, MR-incompatible prosthetic valves, metallic implants, foreign metallic body)
  • active uncontrolled gastrointestinal disorders including ulcerative colitis, Crohn's disease, indeterminate colitis, severe irritable bowel syndrome, persistent infectious gastroenteritis, persistent or chronic diarrhea of unknown etiology, recurrent Clostridium difficile infection
  • major surgery of the GI tract, in the past five years. Any major bowel resection at any time
  • intake of antibiotics in the last 2 months

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Long-term fastingLong-term fasting according to the Buchinger Wilhelmi fasting programThe participants will undergo 6-12 fasting days according to the Buchinger Wilhelmi fasting program
Primary Outcome Measures
NameTimeMethod
Changes in the composition of the quadricepsBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in HDL cholesterol efflux capacityBaseline and changes at the end of fasting as well as one and four months afterwards

measured in serum by a standardized used radioisotopic technique

Changes in the composition of the heartBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in the composition of the kidneyBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in HS-Omega-3 IndexBaseline and changes at the end of fasting as well as one and four months afterwards

Determination of fatty acid (C 14:0; 16:0; 18:0; 20:0; 22:0; 24:0; 16:1 n-7; 18:1 n-9; 20:1 n-9; 24:1 n-9; 18:2 n-6; 18: 3 n-6; 20: 3 n-6; 22:2 n-6; 20:4 n-6; 22:4 n-6; 22:5 n-6; 18: 3 n-3; 20:5 n-3; 22:5 n-3; 22:6 n-3; 16:1 n-7t; 18:1 n-9t; 18:2 n-6tt; 18:2 n-6ct; 18:2 n-6tc) in erythrocyte membranes with highly standardized analytical procedure

Changes in faecal microbiota composition and function (carbohydrate metabolism)Baseline and changes after an average of 10 (+/-3) fasting days

Shotgun metagenomics, 5Gb of DNA sequencing data.

Changes in the composition of the spleenBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in the composition of the adipose tissueBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in serum cholesterol loading capacityBaseline and changes at the end of fasting as well as one and four months afterwards

measured in serum using radioactive cholesterol loaded macrophages

Changes in whole body compositionBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in the composition of the liverBaseline and changes at the end of fasting as well as one and four months afterwards

Fat mass, lean mass, water content measured by magnetic resonance imaging

Changes in metabolomeBaseline and changes after 3 fasting days, the end of fasting as well as one and four months afterwards

using an untargeted metabolomics approach to investigate changes in the metabolome, with a focus on the polyamine biosynthetic pathway at the cellular level in PBMCs and compare them with changes in the circulating plasma/serum metabolome

Changes in hydrogen sulfide production capacityBaseline and changes at the end of fasting as well as one and four months afterwards

measured in serum and urine using the lead acetate assay

Secondary Outcome Measures
NameTimeMethod
Changes in persulfidationBaseline, and changes after 3 fasting days, at the end of fasting as well as one and four months afterwards

persulfidation in serum and urine

Changes in GlycABaseline and changes at the end of fasting as well as one and four months afterwards

determined in serum

Changes in mean diffusivity (MD)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in cardiovascular fitnessBaseline and changes at the end of fasting as well as one and four months afterwards

using the maximal oxygen consumption (VO2max)

Changes in muscle metabolism and mitochondrial oxidative capacity: TauPCr(s)Baseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in muscle metabolism and mitochondrial oxidative capacity: ATP concentrationBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in muscle metabolism and mitochondrial oxidative capacity: T1 of metabolites at restBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in fiber strain (Eff)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in fractional anisotropy (FA)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in systolic cardiac functionBaseline and changes at the end of fasting as well as one and four months afterwards

global and regional function (right and left ejection fraction, right and left end-diastolic and end-systolic volumes, peak regional strains (circumferential, longitudinal strain) measured with magnetic resonance imaging

Changes in apparent diffusion coefficient (ADC)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in muscle metabolism and mitochondrial oxidative capacity: PCr hydrolysis (%)Baseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in multiparametric muscle quantification: T2Baseline and changes at the end of fasting as well as one and four months afterwards

measured with quantitative magnetic impedance imaging

Changes in multiparametric muscle quantification: T2 * relaxation timeBaseline and changes at the end of fasting as well as one and four months afterwards

measured with quantitative magnetic impedance imaging

Changes in brain morphometryBaseline and changes at the end of fasting as well as one and four months afterwards

measured by magnetic resonance imaging

Changes in cardiac massBaseline and changes at the end of fasting as well as one and four months afterwards

measured by magnetic resonance imaging

Changes in lower limbs (quadriceps, hamstrings, calves)Baseline and changes at the end of fasting as well as one and four months afterwards

measured by magnetic resonance imaging

Changes in diastolic cardiac functionBaseline and changes at the end of fasting as well as one and four months afterwards

global and regional diastolic function (peak filling rate, torsion rate, diastolic strain rate) measured with magnetic resonance imaging

Changes in muscle metabolism and mitochondrial oxidative capacity: PCr concentrationBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in muscle metabolism and mitochondrial oxidative capacity: Pi concentrationBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in oxidized phospholipidsBaseline and changes at the end of fasting as well as one and four months afterwards

determined in serum

Changes in enzymesBaseline and changes after 3 fasting days, the end of fasting as well as one and four months afterwards

immunoblotting of relevantly altered enzymes in PBMCs

Changes in lumbosacral muscle massBaseline and changes at the end of fasting as well as one and four months afterwards

measured by magnetic resonance imaging

Changes in helix angle (HA)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in paraoxonase (PON-1) activityBaseline and changes at the end of fasting as well as one and four months afterwards

determined in serum

Changes in proprotein convertase subtilisin/kexin type 9 (PCSK9)Baseline and changes at the end of fasting as well as one and four months afterwards

determined in serum by ELISA

Changes in muscle metabolism and mitochondrial oxidative capacity: pH at rest and post exercise in mMBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in muscle metabolism and mitochondrial oxidative capacity: PCr consumptionBaseline and changes at the end of fasting as well as one and four months afterwards

during ergometric effort in MRI at the level of the sural muscle (31P spectroscopy)

Changes in sulfur compoundsBaseline and changes after 3 fasting days, at the end of fasting as well as one and four months afterwards

amino acids (using a targeted approach), thiosulfate (measured using the monobromobimane method using HPLC and LC-MS/MS), cysteine and cystine (use the S-sulfocysteine (SSC) method which is a HPLC-based method using automated precolumn derivatization with OPA and UV detection at 338 nm) in serum and urine

Changes in multiparametric muscle quantification: susceptibility (chi)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with quantitative magnetic impedance imaging

Changes in DNA methylationBaseline and changes at the end of fasting as well as one and four months afterwards

biomarker of biological aging using erythrocytes

Changes in serum amyloid A levelsBaseline and changes at the end of fasting as well as one and four months afterwards

determined in serum

Changes in lipoprotein transfer enzymesBaseline and changes at the end of fasting as well as one and four months afterwards

CETP activity, determined as U/ml using a commercially available assay

Changes in chylomicronsBaseline and changes at the end of fasting as well as one and four months afterwards

determined in serum

Changes in multiparametric muscle quantification: fat fraction (PDFF)Baseline and changes at the end of fasting as well as one and four months afterwards

measured with quantitative magnetic impedance imaging

Changes in quadricipital maximum voluntary contractionBaseline and changes at the end of fasting as well as one and four months afterwards

measured with magnetic impedance imaging

Changes in thiosulfate levelsBaseline and changes after 3 fasting days, at the end of fasting as well as one and four months afterwards

measured using the monobromobimane method using HPLC and LC-MS/MS

Changes in cysteine and cystine levelsBaseline and changes after 3 fasting days, at the end of fasting as well as one and four months afterwards

using the S-sulfocysteine (SSC) method which is a HPLC-based method using automated precolumn derivatization with OPA and UV detection at 338 nm in serum and urine

Changes in amino acidsBaseline and changes after 3 fasting days, at the end of fasting as well as one and four months afterwards

using a targeted approach in serum and urine

Trial Locations

Locations (1)

Buchinger Wilhelmi clinic

🇩🇪

Überlingen, Germany

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