International consensus on fasting terminology

Cell Metabolism, vol. 36, pp. 1779–1794.e4

Abstract

Although fasting is increasingly applied for disease prevention and treatment, consensus on terminology is lacking. Using Delphi methodology, an international, multidisciplinary panel of researchers and clinicians standardized definitions of various fasting approaches in humans. Five online surveys and a live online conference were conducted with 38 experts, 25 of whom completed all 5 surveys. Consensus was achieved for the following terms: "fasting" (voluntary abstinence from some or all foods or foods and beverages), "modified fasting" (restriction of energy intake to max. 25% of energy needs), "fluid-only fasting," "alternate-day fasting," "short-term fasting" (lasting 2-3 days), "prolonged fasting" (≥4 consecutive days), and "religious fasting." "Intermittent fasting" (repetitive fasting periods lasting ≤48 h), "time-restricted eating," and "fasting-mimicking diet" were discussed most. This study provides expert recommendations on fasting terminology for future research and clinical applications, facilitating communication and cross-referencing in the field.

Authors 43

1. Daniela A. Koppold corresponding

   Humboldt-Universität zu Berlin · Berlin Institute of Health at Charité - Universitätsmedizin Berlin · Immanuel Krankenhaus · Charité - Universitätsmedizin Berlin

   Affiliation as printed

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany; Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany; Charité Competence Center for Traditional and Integrative Medicine (CCCTIM), Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany. Electronic address: daniela.koppold@charite.de

   Charité Competence Center for Traditional and Integrative Medicine (CCCTIM), Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany

   Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

2. Carolin Breinlinger corresponding

   Humboldt-Universität zu Berlin · Charité - Universitätsmedizin Berlin

   Affiliation as printed

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany. Electronic address: carolin.breinlinger@charite.de

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

3. Etienne Hanslian

   Humboldt-Universität zu Berlin · Charité - Universitätsmedizin Berlin

   Affiliation as printed

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

4. Christian S. Keßler

   Humboldt-Universität zu Berlin · Immanuel Krankenhaus · Charité - Universitätsmedizin Berlin

   Affiliation as printed

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany; Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

   Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

5. Holger Cramer

   Robert Bosch Hospital · Universitätsklinikum Tübingen · Bosch Health Campus · University of Tübingen

   Affiliation as printed

   Institute for General Practice and Interprofessional Care, University Hospital Tübingen, Tübingen, Germany; Robert Bosch Center for Integrative Medicine and Health, Bosch Health Campus, Stuttgart, Germany

   Institute for General Practice and Interprofessional Care, University Hospital Tübingen, Tübingen, Germany

   Robert Bosch Center for Integrative Medicine and Health, Bosch Health Campus, Stuttgart, Germany

6. Anika Rajput Khokhar

   Humboldt-Universität zu Berlin · Charité - Universitätsmedizin Berlin

   Affiliation as printed

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany; Department of Dermatology, Venereology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

   Department of Dermatology, Venereology and Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany

   Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

7. Courtney M. Peterson

   University of Alabama at Birmingham

   Affiliation as printed

   Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL, USA

8. Grant M. Tinsley

   Texas Tech University

   Affiliation as printed

   Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, TX 79409, USA

9. Claudio Vernieri

   IFOM · Fondazione IRCCS Istituto Nazionale dei Tumori

   Affiliation as printed

   Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy; IFOM ETS, the AIRC Institute of Molecular Oncology, Milan, Italy

   IFOM ETS, the AIRC Institute of Molecular Oncology, Milan, Italy

   Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy

10. Richard J. Bloomer

    University of Memphis

    Affiliation as printed

    College of Health Sciences, The University of Memphis, Memphis, TN 38152, USA

11. Michael Boschmann

    Max Delbrück Center · Charité - Universitätsmedizin Berlin

    Affiliation as printed

    Experimental & Clinical Research Center - A joint co-operation between Charité Universitätsmedizin und Max-Delbrück Center for Molecular Medicine in the Helmholtz Association, Clinical Research Unit, Berlin, Germany

12. Nicola Luigi Bragazzi

    York University

    Affiliation as printed

    Department of Mathematics and Statistics, Laboratory for Industrial and Applied Mathematics (LIAM), York University, Toronto, ON, Canada

13. Sebastian Brandhorst

    University of Southern California

    Affiliation as printed

    Longevity Institute, Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA

14. Kelsey Gabel

    University of Illinois Chicago

    Affiliation as printed

    Department of Kinesiology and Nutrition, University of Illinois at Chicago, 1919 West Taylor Street, Chicago, IL 60612, USA

15. Alan C. Goldhamer
    Affiliation as printed

    TrueNorth Health Foundation, Santa Rosa, CA 95404, USA; TrueNorth Health Center, Santa Rosa, CA 95404, USA

    TrueNorth Health Center, Santa Rosa, CA 95404, USA

    TrueNorth Health Foundation, Santa Rosa, CA 95404, USA

16. Martin M. Grajower

    Albert Einstein College of Medicine

    Affiliation as printed

    Division of Endocrinology, Albert Einstein College of Medicine, Bronx, New York, NY, USA

17. Michelle Harvie

    University of Manchester · Manchester University NHS Foundation Trust

    Affiliation as printed

    Prevent Breast Cancer Research Unit, The Nightingale Centre, Manchester University NHS Foundation Trust, Manchester, England; Division of Cancer Sciences, The University of Manchester, Manchester, England

    Division of Cancer Sciences, The University of Manchester, Manchester, England

    Prevent Breast Cancer Research Unit, The Nightingale Centre, Manchester University NHS Foundation Trust, Manchester, England

18. Leonie Kaye Heilbronn

    South Australian Health and Medical Research Institute · The University of Adelaide

    Affiliation as printed

    Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia; Nutrition, Metabolism & Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia

    Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia

    Nutrition, Metabolism & Gut Health, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia

19. Spyridon Ν. Karras

    Aristotle University of Thessaloniki

    Affiliation as printed

    Laboratory of Biological Chemistry, Medical School, Aristotle University, 54636 Thessaloniki, Greece

20. Jost Langhorst

    Sozialstiftung Bamberg · University of Duisburg-Essen

    Affiliation as printed

    Department for Internal and Integrative Medicine, Sozialstiftung Bamberg Hospital, Bamberg, Germany; Department for Integrative Medicine, University of Duisburg-Essen, Medical Faculty, Bamberg, Germany

    Department for Integrative Medicine, University of Duisburg-Essen, Medical Faculty, Bamberg, Germany

    Department for Internal and Integrative Medicine, Sozialstiftung Bamberg Hospital, Bamberg, Germany

21. Eva Lischka

    Buchinger Wilhelmi

    Affiliation as printed

    Klinik Buchinger Wilhelmi, Überlingen, Germany

22. Frank Madeo

    University of Graz · BioTechMed-Graz

    Affiliation as printed

    BioTechMed Graz, Graz, Austria; Institute of Molecular Biosciences, University of Graz, Graz, Austria; Field of Excellence BioHealth, University of Graz, Graz, Austria

    BioTechMed Graz, Graz, Austria

    Field of Excellence BioHealth, University of Graz, Graz, Austria

    Institute of Molecular Biosciences, University of Graz, Graz, Austria

23. Sarah Jayne Mitchell

    Ludwig Cancer Research · Princeton University · Ludwig Cancer Research

    Affiliation as printed

    Ludwig Princeton Branch, Ludwig Institute for Cancer Research, Princeton University, Princeton, NJ, USA

24. Ioannis A. Papagiannopoulos
    Affiliation as printed

    Vatopaidi Monastery Hospital, 63086 Mount Athos, Greece

25. Maria Papagiannopoulou
    Affiliation as printed

    Medical Office for Fasting Therapy, Danaedon 24A, Chalandri, 15232 Athens, Greece

26. Hanno Pijl Aachen Department of Internal Medicine

    Leiden University Medical Center

    Affiliation as printed

    Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands

27. Éric Ravussin

    Pennington Biomedical Research Center

    Affiliation as printed

    Pennington Biomedical Research Center, Baton Rouge, LA, USA

28. Martha Ritzmann-Widderich
    Affiliation as printed

    Praxis für Ernährungsmedizin und Prävention in Rottweil, Hochbrücktorstraße 22, 78628 Rottweil, Germany

29. Krista A Varady

    University of Illinois Chicago

    Affiliation as printed

    Department of Kinesiology and Nutrition, University of Illinois at Chicago, 1919 West Taylor Street, Chicago, IL 60612, USA

30. Lilian Adamidou

    AHEPA University Hospital

    Affiliation as printed

    Department of Dietetics and Nutrition, AHEPA University Hospital, Thessaloniki, Greece

31. Mélika Chihaoui

    Tunis University · Hôpital La Rabta · Faculté de médecine de Tunis · Tunis El Manar University

    Affiliation as printed

    Department of Endocrinology, University Hospital La Rabta, Faculty of medicine of Tunis, University Tunis El Manar, Tunis, Tunisia

32. Rafael de Cabo

    National Institute on Aging

    Affiliation as printed

    Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA

33. Mohamed M. Hassanein

    Dubai Hospital

    Affiliation as printed

    Department of Endocrinology and Diabetes, Dubai Hospital, Dubai Academic Health Cooperation, United Arab Emirates

34. Nader G. Lessan

    Imperial College London Diabetes Centre

    Affiliation as printed

    The Research Institute, Imperial College London Diabetes Centre, Abu Dhabi, United Arab Emirates

35. Valter Daniel Longo

    University of Southern California · IFOM · Italian Association for Cancer Research

    Affiliation as printed

    IFOM ETS, the AIRC Institute of Molecular Oncology, Milan, Italy; Longevity Institute, Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA

    IFOM ETS, the AIRC Institute of Molecular Oncology, Milan, Italy

    Longevity Institute, Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA

36. Emily N. C. Manoogian

    Salk Institute for Biological Studies

    Affiliation as printed

    Regulatory Biology Department, Salk Institute for Biological Studies, La Jolla, CA, USA

37. Mark P. Mattson

    Johns Hopkins University

    Affiliation as printed

    Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA

38. Joseph Brent Muhlestein

    Intermountain Medical Center

    Affiliation as printed

    The Intermountain Medical Center, Murray, UT, USA

39. Satchidananda Panda

    Salk Institute for Biological Studies

    Affiliation as printed

    Regulatory Biology Department, Salk Institute for Biological Studies, La Jolla, CA, USA

40. Sousana Κ. Papadopoulou

    International Hellenic University

    Affiliation as printed

    Department of Nutritional Sciences and Dietetics, School of Health Sciences, International Hellenic University, 57001 Thessaloniki, Greece

41. Nikolaos E. Rodopaios

    University of Crete

    Affiliation as printed

    Department of Social Medicine, Preventive Medicine and Nutrition Clinic, School of Medicine, University of Crete, Voutes, 71003 Iraklion, Greece

42. Rainer Stange

    Humboldt-Universität zu Berlin · Immanuel Krankenhaus · Charité - Universitätsmedizin Berlin

    Affiliation as printed

    Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany; Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

    Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

    Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany

43. Andreas Michalsen

    Humboldt-Universität zu Berlin · Immanuel Krankenhaus · Charité - Universitätsmedizin Berlin

    Affiliation as printed

    Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany; Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

    Department of Internal Medicine and Nature-Based Therapies, Immanuel Hospital Berlin, 14109 Berlin, Germany

    Institute of Social Medicine, Epidemiology and Health Economics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117 Berlin, Germany