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OpenTrials
Completed

NCT Number: NCT04452916

Physiological Response to 5 Days Fasting

To investigate energy metabolism, anthropometry, blood pressure, gut microbiome, serum metabolome, glucose variability and neural mechanisms of food choice and mood before and after 5 days of fasting as well as their persistence in healthy men and women.

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Key information

Conditions

Healthy

Age range

20 year–50 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Charité Universitätsmedizin Berlin

Berlin, 13125, Germany

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Men and women
  • 20-50 years
  • Body mass index 20-30 kg/m2

Exclusion criteria

  • Clinically relevant heart, lung, liver, and kidney diseases
  • Any prescribed medication (except for oral contraceptives)
  • Current or chronic infection
  • Intake of antibiotics within 6 months before study entry
  • Fasting week within 6 months before study entry
  • Habitual use of dietary supplements
  • Food intolerances
  • Pregnancy, lactation
  • Vegan diet
  • Smokers
  • In addition for fMRI: sensorineural hearing loss, tinnitus, metal implants, electric devices

Treatment and study plan

Buchinger fasting

Other

Caloric intake of < 250 kcal/d for 5 days

Primary outcomes

  1. Resting Energy Expenditure

    Time frame: 6-th day of fasting compared to baseline

    Measured by indirect calorimetry (kcal/d)

Secondary outcomes

  1. Resting Energy Expenditure - Recovery

    Time frame: 12 weeks after fasting compared to baseline

    Measured by indirect calorimetry (kcal/d)

  2. Resting Respiratory Exchange Ratio

    Time frame: 6-th day of fasting and 28 days after fasting compared to baseline

    Measured by indirect calorimetry

  3. Office systolic blood pressure

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Mean of five consecutive blood pressure measurements (mmHg)

  4. Office diastolic blood pressure

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Mean of five consecutive blood pressure measurements (mmHg)

  5. Fecal microbiome composition

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Measured by 16S Sequencing

  6. Fecal and serum metabolome

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Measured by mass spectrometry

  7. Change in immune cell phenotypes

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Peripheral blood effector T cell frequencies (Percent)

  8. Glucose variability

    Time frame: From 3 days before until 6 days after fasting

    Measured by continuous glucose monitoring over 14 days

  9. Neural correlates of emotion processing

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Measured by functional Magnetic Resonance Imaging

  10. Neural correlates of food-specific delay discounting

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Measured by functional Magnetic Resonance Imaging

  11. Perceived Stress Questionaire (PSQ)

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Range 0-100, with 0 indicating no perceived stress

  12. Perceived Self Efficiency

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Range 10-40, with 40 indicating highest self efficiency

  13. PANAS Positive Affect Subscale (GESIS Panel)

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Range 10-50, with 50 indicating highest positive affect

  14. PANAS Negative Affect Subscale (GESIS Panel)

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Range 10-50, with 50 indicating highest negative affect

  15. International Physical Activity Questionaire (IPAQ, long version)

    Time frame: 6-th day of fasting and 12 weeks after fasting compared to baseline

    Time for moderate and vigorous activity (hours, minutes)

Sponsors and collaborators

Lead sponsor

Charite University, Berlin, Germany

Other

Registry information

Official study title

Physiological Response to Prolonged Fasting in Healthy Volunteers

Important dates

Study start
2020
Primary completion
2022
Study completion
2024
First posted
Jul 1, 2020
Registry last updated
Aug 21, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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