Skip to main content
Download PDF
  • Research article
  • Open access
  • Published:

Is fasting safe? A chart review of adverse events during medically supervised, water-only fasting

BMC Complementary and Alternative Medicine volume 18, Article number: 67 (2018) Cite this article

Abstract

Background

Evidence suggests that fasting, during which only water is consumed, results in potentially health promoting physiological effects. However, peer-reviewed research assessing the safety of water-only fasting is lacking. To address this, we conducted a chart review to describe adverse events (AEs) that occurred during medically supervised, water-only fasting.

Methods

Electronic charts from patient visits to a residential medical facility from 2006 to 2011 were reviewed. Patients who were at least 21 years of age and water-only fasted for ≥2 consecutive days with a refeeding period equal to half of the fast length were included. Out of 2539 charts, 768 visits met our inclusion and exclusion criteria. AEs were abstracted from chart notes and classified according to CTCAE (v4.03) and MedDRA (v12.1) terminology. Descriptive analysis of AEs is reported.

Results

During the protocol period, the highest grade AE (HGAE) in 555 visits was a grade 2 event or lower, in 212 visits it was a grade 3 event, in 1 visit it was a grade 4 event, and there were no grade 5 events. There were 2 (0.002%) visits with a serious adverse event (SAE). The majority of AEs identified were mild (n = 4490, 75%) in nature and known reactions to fasting.

Conclusions

To our knowledge, this is the most comprehensive analysis of AEs experienced during medically supervised, water-only fasting conducted to date. Overall, our data indicate that the majority of AEs experienced were mild to moderate and known reactions to fasting. This suggests that the protocol used in this study can be safely implemented in a medical setting with minimal risk of a SAE.

Peer Review reports

Background

Modern humans evolved to survive periods of food shortage and have voluntarily fasted for at least 2000 years. Fasting is broadly defined as the voluntary abstinence of some or all caloric foods and beverages for therapeutic, spiritual, or political reasons [1]. In the last century, research in animals and humans has uncovered several potentially health-promoting physiologic responses to fasting including ketogenesis, hormone modulation, reduced oxidative stress and inflammation, and increased stress resistance, lipolysis, and autophagy [1,2,3,4]. Clinical research in humans also indicates that fasting improves hypertension, [5, 6] rheumatoid arthritis, [7] cardiovascular disease, [8, 9] metabolic syndrome, [10, 11] osteoarthritis, [12] fibromyalgia, [13] chronic pain, [14] and quality of life [15].

Wilhelmi de Toledo et al. recently reviewed several fasting methods and established the first peer-reviewed therapeutic fasting guidelines in English (revision of the 2002 German publication [16, 17]). The guidelines specify indications, contraindications, and methods for safe implementation and are based on the Buchinger Method (a modified diet supplying 250–500 kcal/day in the form of vegetable broth, fruit and vegetable juices, and honey). The guidelines are also largely applicable to water-only fasting, which is defined as the complete abstinence of substances except for pure water [18] and is an established method of therapeutic fasting [1,2,3, 19, 20]. Yet it is only briefly described by Wilhelmi de Toledo et al. as a “zero calorie diet” that has not been practiced since the 1970s, when it was primarily used for weight reduction [17].

Therapeutic water-only fasting research did decline following a period in the 1960s and early 1970s when the method was used as an obesity treatment, [21,22,23,24] in part due to reports of serious complications, including death, in some fasting subjects [25,26,27,28,29,30]. During this time, it was common to arbitrarily implement fasts lasting 60 days or longer [29, 31, 32] and to administer chemical compounds to facilitate prolonged fasts. [25, 28, 33, 34]. Additionally, physicians and researchers did not always screen subjects for contraindications, terminate fasts upon complication, or properly refeed subjects, [25, 26, 28, 29] all of which are necessary for the safe implementation of water-only fasts [1,2,3]. Therefore, it is difficult to conclude if water-only fasting is inherently dangerous or if the complications were caused by unintentionally harmful fasting practices.

Despite the documented decline in fasting research and contrary to claims by Wilhemi de Toledo et al., [17] water-only fasting was not entirely discontinued in the 1970s. It has since been utilized for many therapeutic purposes such as the treatment of hypertension, [5, 6] cardiovascular disease, [9] appendicitis, [35] follicular lymphoma, [36] and as an adjunct to chemotherapy [37]. Importantly, previous therapeutic implementation and clinical research led to the development of a water-only fasting protocol (see Methods) that safeguards against serious complications and minimizes minor reactions [1,2,3]. Nevertheless, there is a lack of objective, peer-reviewed data on the safety of water-only fasting.

Therefore, we were motivated to systematically assess the safety of medically supervised, water-only fasting. To this end, we reviewed and characterized the adverse events (AEs) experienced by patients who water-only fasted at TrueNorth Health Center (TNHC) over a five-year period using Common Terminology Criteria for Adverse Events (CTCAE v4.03 [38]) and Medical Dictionary for Regulatory Activities (MedDRA v12.1 [39]). We report the severity, frequency, and nature of patient AEs that occurred during this time.

Methods

Setting

TNHC (www.truenorthhealth.com) is an integrative medical facility in Santa Rosa, CA, USA that offers a residential health education program specializing in water-only fasting and dietary intervention. Patients in this study had access to medical, naturopathic, and chiropractic doctors. Private rooms, 24-h medical supervision, and daily educational activities were also provided.

Water-only fasting protocol

The detailed water-only fasting protocol used in this study is within the standards established by the International Association of Hygienic Physicians (Additional file 1: Supplementary Methods) [40]. Briefly, patients electing to water-only fast at TNHC routinely underwent a comprehensive physical, neurological, and psychological examination including medical history, urinalysis, complete blood count with differentials, and comprehensive metabolic panel. Patients with contraindications or taking medications that could not be discontinued, with the exception of thyroid medications which can be continued at a reduced concentration, were not admitted for water-only fasting.

Patients were instructed to eat a diet of fresh raw fruits and vegetables and steamed starchy vegetables for at least 2 days before fasting. During the fast, patients remained on site, drank a minimum of 40 ounces of distilled water per day, and minimized physical activity. Medical staff monitored fasting patients twice daily and recorded vital signs and symptoms into chart notes. Urinalysis and the aforementioned blood tests were repeated weekly or as directed by a clinician. Water-only fasts were discontinued when symptoms stabilized, the patient requested termination of the fast, or the clinician deemed it necessary for medical reasons.

Following the fast, patients refed for a period of time lasting half of the fast length. Standard refeeding consisted of five phases (1 phase for each 7–10 days of water-only fasting) (Supplementary Methods), beginning with juice and followed by gradual introduction of solid plant foods (free from added sugar, oil, and salt) (Additional file 1: Supplementary Methods). Once patients were eating solid foods, the gradual reintroduction of moderate exercise was allowed. During the refeeding process, patients were offered twice-daily monitoring by clinicians.

Database design and study population

Electronic charts from May, 2006 to December 31, 2011 were extracted into a single relational database (MS Access). The data collected included age, gender, chief complaints, treatment status (i.e., water, juice, broth, or food), and clinical chart notes. Chief complaints data were derived from self-reports and clinical diagnoses.

The study included visits by patients who water-only fasted for at least two consecutive days and refed for at least half of the fast length. The study excluded visits by patients who fasted prior to Jan. 1, 2007 because of incomplete data records, were under twenty-one years old, water-only fasted for one day or less because this length is defined as an intermittent fast and generally does not require medical supervision, [41] interrupted the water-only fast with any amount of vegetable broth or juice and/or fruit juice, had supervised refeeding less than half of the fast length, or if there were insufficient data to determine treatment status on a given day (Fig. 1). Out of 2539 visits, 768 were included in our study. Of the selected visits, the analysis dataset included visit days from the day fasting began to day the refeeding period (1/2 length of fast post-fast) ended. For fasts of an odd number of days, the refeeding period was rounded up to the nearest integer (e.g., if a visit had 3 days of fasting, then analysis data included 2 days of refeeding). There was no information about the condition of the patient other than treatment status for 5.2% (496/9570) of total visit days (312 during fasting/184 refeeding).

Fig. 1
figure 1

Study population flow chart

Full size image

Adverse event identification and coding

Data on AEs were collected from clinical chart notes of self-reported symptoms, clinical and diagnostic findings, and medical management of symptoms. Laboratory values were not systematically included due to data incompleteness. The CTCAE (v4.03) scale was used to grade AE severity: AE1 – mild, AE2 – moderate, AE3 – severe, AE4 – life threatening or disabling, and AE5 – death. AEs were characterized using the MedDRA (v12.1) terminology according to the system organ class (SOC), which uses the highest level term (HLT), including anatomical or physiological system, etiology, and/or purpose, and the lowest level term (LLT). Pain-related AEs, reported on a visual-analog scale (VAS) from 0 to 10, were reported as follows: AE1 = VAS 1–4, AE2 = VAS 5–7, and AE3 = VAS 8–10 [42, 43]. A serious adverse event (SAE) was determined based on the definition used by the Department of Health and Human Services [44]. A codification guide was created to ensure that there was consistent codification of AEs. A single trained clinician (J.S.F) identified, reviewed, and classified AEs, according to the above criteria, for each daily entry in the electronic chart note. A user interface within the relational database (MS Access) was used for direct data entry of the codified data. One week after the conclusion of data abstraction, intra-rater reliability was assessed based on a random sample of daily logs. The dataset is available from the Dryad repository, https://doi.org/10.5061/dryad.6cg6j.

Intra-rater consistency

Inter-rater reliability was assessed using a blind, random sample of daily logs (n = 645, 7%). There was 80.5% agreement between MedDRA codes identified in the original coding and secondary assessment. Of these, the weighted kappa statistic (squared weights) measuring agreement of the AE grade was 0.92 [45].

Adverse event descriptive analysis

Visits were stratified by water-only fast length: 2–7 (short), 8–14 (medium), 15–21 (long), or 22+ (extended) days. These categories were chosen to represent lengths of typical fasts. Within visits, days were grouped by fasting and refeeding status. Summary statistics of the study population at the patient and visit levels were tabulated. Chief complaints were categorized by SOC when possible. For each visit, the highest grade AE (HGAE) experienced (of any MedDRA term) and the total AEs were calculated for the fasting, refeeding, and entire protocol periods. Tallies and percentages of HGAE within each of these periods were computed in total and by the fasting length strata. Spearman’s correlation between fasting length strata and HGAE was computed using integer scores for the fasting length strata. For each MedDRA term, counts and percentages of visits with at least one AE of a term were computed for each AE grade and for all AE grades combined. Similar counts and percentages were computed for individual AEs without taking visits into account. We report MedDRA terms that were experienced in more than 10%. Association between a visit’s HGAE and age was assessed graphically and measured with Spearman’s correlation [46]. An association between HGAE and gender was tested using a two-sided Fisher’s exact test. The paired difference in HGAE during fasting versus refeeding was tested using a paired t-test. Kaplan-Meier estimates of cumulative incidence (CI) were computed for each category of fasting length for the following AE categories: any AE, any AE ≥ 2, and any AE ≥ 3 [47]. All AEs of grade 3 or higher were carefully reviewed (A.C.G., T.R.M, J.S.F.), and SAEs were further described by brief narrative. Analyses were performed in R 3.1 using the survival, [48, 49] irr, [45] ggplot2, [50] dplyr, [51] and htmlTable packages [52].

Results

Patient demographics and visit characteristics

We analyzed charts from 768 visits of patients who water-only fasted at TNHC from 2007 to 2011 for at least 2 consecutive days followed by a refeeding period equal to half of the fast length. There were a total of 652 patients, 409 (63%) were female, and the median (interquartile range, IQR) age at first visit was 55 (17.25) years old. Of these, 54 patients fasted 2 times and 23 fasted 3 or more times during the study period.

There were 768 visits, comprising 9570 visit days and 6265 fasting days. The median fasting length was 7 (IQR 6) days; the shortest fast was 2 days and longest fast was 41 days. Of these, there were 446 short (2–7 fasting days, median [IQR] = 5 [3] days), 238 medium (8–14 fasting days, median [IQR] = 10 [3] days), 64 long (14–21 fasting days, median [IQR] = 18 [4] days), and 20 extended (22 or more fasting days, median [IQR] = 27.5 [6.2] days) visits. Table 1 describes chief complaint categories as total counts and as a percentage of total visits. A patient could have had more than one chief complaint per visit. Quality of life, including prevention and fatigue, was the primary reason patients visited TNHC (n = 384, 50%). Other major chief complaint categories included the cardiovascular (n = 193, 25.1%), musculoskeletal (n = 147, 19.1%), gastrointestinal (n = 122, 15.9%), and endocrine (n = 107, 13.9%) systems. Following prevention (n = 358, 46.7%), hypertension (n = 152, 19.7%) was the largest chief complaint category.

Table 1 Chief complaints
Full size table

Adverse events experienced during fasting and refeeding

AEs were classified on a graded scale of 1–5 according to CTCAE (v4.03) and MedDRA (v12.1) criteria (see Methods). HGAE experienced during the fasting, refeeding, and entire protocol period of each visit is presented in Table 2. During the entire protocol period (i.e., fasting and refeeding) for all visit lengths, the HGAE experienced in the majority of visits (n = 555, 72.3%) was grade 2 or lower and in 212 visits (26.6%) it was grade 3. There was a weak positive correlation between fast and refeed length and HGAE (Table 2). There was 1 patient with a grade 4 AE during a medium visit. There were no deaths (AE5) during any visits. There was a weak positive correlation between HGAE and fast duration (Spearman’s ρ = 0.28, p = < 0.001) and a weak positive correlation between HGAE and age (Spearman’s ρ = 0.11, p = 0.002) (Additional file 1: Figure S1a, b). There was no correlation between HGAE and gender (p = 0.628) (Additional file 1: Figure S1c). During refeeding, the mean HGAE was 0.56 less than during fasting (paired t = − 16.28, p = < 0.001).

Table 2 Highest Grade AE experienced by duration of fast
Full size table

Kaplan-Meier CI plots for AEs during fasting and during refeeding are shown in Fig. 2. At day 5 of fasting, the estimated cumulative incidence (ECI) for experiencing any AE was 0.90 (95% CI: 0.88, 0.92) (Fig. 2a). For experiencing any AE ≥ grade 2, the ECI was 0.54 (0.50, 0.58) at day 5 and 0.69 (0.65, 0.73) at day 10 (Fig. 2b). For any AE ≥ grade 3, the ECI was 0.20 (0.17, 0.23) at day 5, 0.28 (0.24, 0.32) at day 10, and 0.32 (0.27, 0.37) at day 15 (Fig. 2c).

Fig. 2
figure 2

Cumulative incidence of adverse events by fast length. Kaplan-Meier curves (solid line) and 95% confidence intervals (dashed line) for (a) any AE; (b) any AE greater than or equal to 2 and; (c) any AE greater than or equal to 3

Full size image

MedDRA classification and HGAE that occur in greater than 10% of visits are presented in Table 3. The results indicate visits during which the subject experienced a given AE classification at least one time; subjects could have experienced more than one AE class during a single visit. During the majority of visits, subjects experienced AEs that were classified as fatigue (n = 370, 48.2%), nausea (n = 247, 32.2%), insomnia (n = 257, 33.5%), headache (n = 231, 30.1%), hypertension (n = 224, 29.2%), presyncope (n = 217, 28.3%), dyspepsia (n = 199, 25.9%), and back pain (n = 197, 25.7%). Presyncope (n = 212) and hypertension (n = 77) occurred in the majority of visits in which grade 2 and grade 3 was the HGAE experienced, respectively. Of the 77 visits with a grade 3 hypertension AE, 75 had hypertension as a chief complaint upon arrival.

Table 3 Number of visits with AEs. Visits may have more than one AE type
Full size table

MedDRA classification and AE grade of the total number of AEs are presented in (Additional file 1: Table S1). There were a total of 5961 AEs. Of these, 75.3% were AE1, 19.6% were AE2, 5.0% were AE3, and 0.0003% were AE4. The most common events were the same as those that occurred in the majority of visits in Table 3.

Serious adverse events

There were two (0.002% of visits) SAEs that required hospitalization. One was a grade 3 dehydration event that occurred on fasting day 3 in a 73-year-old, male patient. The patient developed headache, fever, and increased blood pressure. He was taken to an emergency facility, where he received antibiotics for potential upper respiratory infection and intravenous (IV) electrolytes for dehydration and was kept under inpatient observation for 3 days. The patient fully recovered and returned to TNHC. The other was a grade 4 hyponatremia event that occurred on fasting day 9 in a 70-year-old, male patient. The patient developed difficulty with speech and was immediately transported to an emergency facility by ambulance. Upon evaluation at the emergency facility, the patient was diagnosed with hyponatremia, administered IV electrolytes, and kept under inpatient observation for 4 days. The patient fully recovered but did not return to TNHC.

Discussion

To our knowledge this is the first peer-reviewed assessment of AEs experienced during medically supervised, water-only fasting. We found that in the majority of visits (65.8%) the HGAE experienced was mild (grade 1) to moderate (grade 2) and there was no AE in 6.5% of visits. A severe but not life threatening AE (grade 3) was the highest grade in 27.6% of visits, and a life threatening AE (grade 4) was the highest grade in 1 visit. An SAE occurred in only 2 visits, and there were no deaths. HGAE and fast duration were positively correlated. Subjects also had less severe AEs during refeeding in comparison with fasting. The degree to which these observations are due to treatment (i.e., fasting) emergent AEs, pre-existing conditions, longer observation times, and/or other factors is unclear. Further research is necessary to better understand these relationships.

AEs that were commonly experienced during visits, including nausea, headache, insomnia, back pain, dyspepsia, and fatigue, were predominately mild, grade 1 events and are reactions that are known to occur during fasting [1, 2]. The exceptions were presyncope and hypertension. Presyncope is also known to occur in response to fasting, [1] and is always defined as a moderate, grade 2 event [38]. Hypertension was the largest category of grade 3 events – both for visits in which the highest event was grade 3 and for the total number of individual grade 3 events – and is not reported to occur in response to fasting. Conversely, water-only fasting has been shown to reduce blood pressure in hypertensive patients [5, 6]. Indeed, we found that in 97% of visits with a grade 3 hypertension AE, the patient had hypertension as a chief complaint. This suggests that the grade 3 hypertensive events occurred in patients being treated for hypertension and that water-only fasting is unlikely a causal factor in the participant’s high blood pressure.

A limitation in our assessment of water-only fasting safety is that patient notes were not recorded with the intent to assess AEs. This resulted in data incompleteness and the potential for other errors (e.g., inaccurate terminology usage and patient prompting). Data incompleteness prevented conclusive assignment of attribution, identification of treatment emergent AEs, and analysis of confounders. This could lead to an overestimation of AEs attributable to water-only fasting as seems to be observed for hypertensive events in patients with hypertension as their chief complaint. Additionally, this study reviewed charts from a single site and the findings are therefore specific to TNHC and may not be applicable to other fasting centers. However, to our knowledge, there are currently no other facilities conducting medically supervised, water-only fasting. Furthermore, the data were abstracted by a single clinician (J.S.F.) trained in MedDRA terminology and CTCAE grading but who was not blind to the study question. To address this limitation, we implemented multiple data consistency queries and performed an intra-rater assessment on a random sample of daily logs. Lastly, although we have quantified the safety profile of water-only fasting in the TNHC population, any judgment of the relative safety of water-only fasting is necessarily descriptive in nature as we did not identify a comparison group(s).

Our purpose in highlighting the Wilhelmi de Toledo et al. article [17] was not to criticize a seminal paper on fasting guidelines but rather to underscore two important points. The first is that even though fasting has been utilized by humans for millennia and the medical community for at least a century it was not until 2013 that peer-reviewed fasting guidelines were published in the English language. These guidelines as well as an increase in scientific literature on the benefits of various types of fasting support the credibility and emerging acceptance of this intervention [4, 53,54,55]. The second point is that within the fasting community – not to mention the greater medical community – there are claims, unsubstantiated by research, about the utilization and safety of water-only fasting (i.e., that it is not utilized and unsafe). Although controlled clinical trials are lacking, water-only fasting is utilized therapeutically and the data from this retrospective safety study suggests that adverse events experienced during medically supervised, water-only fasting are tolerable.

Conclusions

Overall, our data indicate that the majority of AEs experienced during medically supervised, water-only fasting are mild to moderate in nature and are known reactions to fasting. This suggests that the TNHC protocol can be safely implemented in a medical setting with minimal risk of a severe or SAE. This study also provides a basis by which further research into the safety and efficacy of this intervention can be conducted.

Abbreviations

AE:

Adverse event

CI:

Cumulative incidence

CTCAE:

Common Terminology Criteria for Adverse Events

ECI:

Estimated cumulative incidence

HGAE:

Highest grade adverse event

HLT:

Highest level term

IQR:

Interquartile range

IV:

Intravenous

LLT:

Lowest level term

MedDRA:

Medical Dictionary for Regulatory Activities

SAE:

Serious adverse event

SOC:

System organ class

TNHC:

TrueNorth Health Center

VAS:

Visual analog scale

References

  1. Fredericks R. Fasting: an exceptional human experience. San Jose: All Things Published Well; 2013.

    Google Scholar 

  2. Goldhamer AC, Helms S, Salloum TK. Fasting. 4th ed. St. Louis: Elsevier Churchill Livingstone; 2013.

    Google Scholar 

  3. Furhman J. Fasting and eating for health: a medical doctor's program for conquering disease. New York: St. Martin's Griffin; 1995.

    Google Scholar 

  4. Longo VD, Mattson MP. Fasting: molecular mechanisms and clinical applications. Cell Metab. 2014;19(2):181–92.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Goldhamer A, Lisle D, Parpia B, Anderson SV, Campbell TC. Medically supervised water-only fasting in the treatment of hypertension. J Manip Physiol Ther. 2001;24(5):335–9.

    Article  CAS  Google Scholar 

  6. Goldhamer AC, Lisle DJ, Sultana P, Anderson SV, Parpia B, Hughes B, Campbell TC. Medically supervised water-only fasting in the treatment of borderline hypertension. J Altern Complement Med. 2002;8(5):643–50.

    Article  PubMed  Google Scholar 

  7. Kjeldsen-Kragh J, Haugen M, Borchgrevink CF, Laerum E, Eek M, Mowinkel P, Hovi K, Forre O. Controlled trial of fasting and one-year vegetarian diet in rheumatoid arthritis. Lancet. 1991;338(8772):899–902.

    Article  CAS  PubMed  Google Scholar 

  8. Horne BD, May HT, Anderson JL, Kfoury AG, Bailey BM, McClure BS, Renlund DG, Lappe DL, Carlquist JF, Fisher PW, et al. Usefulness of routine periodic fasting to lower risk of coronary artery disease in patients undergoing coronary angiography. Am J Cardiol. 2008;102(7):814–9.

    Article  PubMed  PubMed Central  Google Scholar 

  9. Horne BD, Muhlestein JB, Lappe DL, May HT, Carlquist JF, Galenko O, Brunisholz KD, Anderson JL. Randomized cross-over trial of short-term water-only fasting: metabolic and cardiovascular consequences. Nutr Metab Cardiovasc Dis. 2013;23(11):1050–7.

    Article  CAS  PubMed  Google Scholar 

  10. Li C, Ostermann T, Hardt M, Ludtke R, Broecker-Preuss M, Dobos G, Michalsen A. Metabolic and psychological response to 7-day fasting in obese patients with and without metabolic syndrome. Forsch Komplementmed. 2013;20(6):413–20.

    Article  PubMed  Google Scholar 

  11. Steiniger J, Schneider A, Bergmann S, Boschmann M, Janietz K. Effects of fasting and endurance training on energy metabolism and physical fitness in obese patients. Forsch Komplementmed. 2009;16(6):383–90.

    Article  PubMed  Google Scholar 

  12. Schmidt S, Stange R, Lischka E, Kiehntopf M, Deufel T, Loth D, Uhlemann C. Uncontrolled clinical study of the efficacy of ambulant fasting in patients with osteoarthritis. Forsch Komplementmed. 2010;17(2):87–94.

    Article  PubMed  Google Scholar 

  13. Michalsen A, Li C, Kaiser K, Ludtke R, Meier L, Stange R, Kessler C. In-patient treatment of fibromyalgia: a controlled nonrandomized comparison of conventional medicine versus integrative medicine including fasting therapy. Evid Based Complement Alternat Med. 2013;2013:908610.

  14. Michalsen A, Kuhlmann MK, Ludtke R, Backer M, Langhorst J, Dobos GJ. Prolonged fasting in patients with chronic pain syndromes leads to late mood-enhancement not related to weight loss and fasting-induced leptin depletion. Nutr Neurosci. 2006;9(5–6):195–200.

    Article  CAS  PubMed  Google Scholar 

  15. Michalsen A, Hoffmann B, Moebus S, Backer M, Langhorst J, Dobos GJ. Incorporation of fasting therapy in an integrative medicine ward: evaluation of outcome, safety, and effects on lifestyle adherence in a large prospective cohort study. J Altern Complement Med. 2005;11(4):601–7.

    Article  PubMed  Google Scholar 

  16. Wilhelmi de Toledo F BA, Burggrabe H, et al. Leitlinien zur Fastentherapie. Forsch Komplementärmed Klass Naturkeilkd. 2002;9:189–98.

  17. Wilhelmi de Toledo F, Buchinger A, Burggrabe H, Holz G, Kuhn C, Lischka E, Lischka N, Lutzner H, May W, Ritzmann-Widderich M, et al. Fasting therapy - an expert panel update of the 2002 consensus guidelines. Forsch Komplementmed. 2013;20(6):434–43.

    Article  PubMed  Google Scholar 

  18. Goldhamer AC. Therapeutic fasting: an introduction to the benefits of a professionally supervised fast in a natural hygiene facility. Health Science. 1987;10-11:16–7.

    Google Scholar 

  19. Burfield-Hazzard L. The pioneers of therapeutic fasting in America. Whitefish: Kessinger Publishing; 2005.

    Google Scholar 

  20. Shelton HM. The hygienic system, vol. III. San Antonio: Dr. Shelton's Health School; 1950.

    Google Scholar 

  21. Bloom WL. Fasting as an introduction to the treatment of obesity. Metabolism. 1959;8(3):214–20.

    CAS  PubMed  Google Scholar 

  22. Drenick EJ, Swendseid ME, Blahd WH, Tuttle SG. Prolonged starvation as treatment for severe obesity. JAMA. 1964;187:100–5.

    Article  CAS  PubMed  Google Scholar 

  23. Duncan GG, Jenson WK, Fraser RI, Cristofori FC. Correction and control of intractable obesity. Practicable application of intermittent periods of total fasting. JAMA. 1962;181:309–12.

    Article  CAS  PubMed  Google Scholar 

  24. Cahill GF Jr, Marliss EB, Aoki TT. Fat and nitrogen metabolism in fasting man. Horm Metab Res. 1970;2(Suppl 2):181–5.

    Google Scholar 

  25. Cubberley PT, Polster SA, Schulman CL. Lactic acidosis and death after the treatment of obesity by fasting. N Engl J Med. 1965;272:628–30.

    Article  CAS  PubMed  Google Scholar 

  26. Spencer IO. Death during therapeutic starvation. Lancet. 1968;2(7569):679–80.

    Article  CAS  PubMed  Google Scholar 

  27. Spencer IO. Death during therapeutic starvation for obesity. Lancet. 1968;1(7555):1288–90.

    Article  CAS  PubMed  Google Scholar 

  28. Garnett ES, Barnard DL, Ford J, Goodbody RA, Woodehouse MA. Gross fragmentation of cardiac myofibrils after therapeutic starvation for obesity. Lancet. 1969;1(7601):914–6.

    Article  CAS  PubMed  Google Scholar 

  29. Runcie J, Thomson TJ. Prolonged starvation--a dangerous procedure. Br Med J. 1970;3(5720):432–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Rose M, Greene RM. Cardiovascular complications during prolonged starvation. West J Med. 1979;130(2):170–7.

    CAS  PubMed  PubMed Central  Google Scholar 

  31. Stewart WK, Fleming LW. Features of a successful therapeutic fast of 382 days' duration. Postgrad Med J. 1973;49(569):203–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Thomson TJ, Runcie J, Miller V. Treatment of obesity by total fasting for up to 249 days. Lancet. 1966;2(7471):992–6.

    Article  CAS  PubMed  Google Scholar 

  33. Gilliland IC. Total fasting in the treatment of obesity. Postgrad Med J. 1968;44(507):58–61.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Scobie IN, MacCuish AC, Kesson CM, McNeil IR. Neutropenia during allopurinol treatment in total therapeutic starvation. Br Med J. 1980;280(6224):1163.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Gershfeld N, Sultana P, Goldhamer A. A case of nonpharmacologic conservative management of suspected uncomplicated subacute appendicitis in an adult male. J Altern Complement Med. 2011;17(3):275–7.

    Article  PubMed  Google Scholar 

  36. Goldhamer AC, Klaper M, Foorohar A, Myers TR. Water-only fasting and an exclusively plant foods diet in the management of stage IIIa, low-grade follicular lymphoma. BMJ Case Rep. 2015;2015.

  37. Safdie FM, Dorff T, Quinn D, Fontana L, Wei M, Lee C, Cohen P, Longo VD. Fasting and cancer treatment in humans: a case series report. Aging (Albany NY). 2009;1(12):988–1007.

    Article  Google Scholar 

  38. Common Terminology Criteria for Adverse Events (CTCAE). In: vol. 4.03: US National Cancer Institute, Division of Cancer Treatment & Diagnosis, Cancer Therapy Evaluation Program; 2010.

  39. CTC CTCAE Mapping Document CTCAE v4.0 to MedDRA 12.1. US National Cancer Institute, Division of Cancer Treatment & Diagnosis, Cancer Therapy Evaluation Program.

  40. Standards of Practice of Fasting Supervision. http://www.iahp.net/fast.htm.

  41. Mattson MP, Longo VD, Harvie M. Impact of intermittent fasting on health and disease processes. Ageing Res Rev. 2017;39:46–58.

    Article  PubMed  Google Scholar 

  42. Boonstra AM, Schiphorst Preuper HR, Balk GA, Stewart RE. Cut-off points for mild, moderate, and severe pain on the visual analogue scale for pain in patients with chronic musculoskeletal pain. Pain. 2014;155(12):2545–50.

    Article  PubMed  Google Scholar 

  43. Kapstad H, Hanestad BR, Langeland N, Rustoen T, Stavem K. Cutpoints for mild, moderate and severe pain in patients with osteoarthritis of the hip or knee ready for joint replacement surgery. BMC Musculoskelet Disord. 2008;9:55.

    Article  PubMed  PubMed Central  Google Scholar 

  44. 45 CFR 46. In: Department of Health and Human Services; 2009.

  45. Gamer M, Lemon J, Fellow I, Singh P. Various Coefficients of Interrater Reliability and Agreement. In: 0.84 edn. R Package; 2012.

  46. Spearman C. The proof and measurement of association between two things. Am J Psychol. 1904;15(1):72–101.

    Article  Google Scholar 

  47. Kaplan EL, Meier P. Nonparametric Estimatino from incomplete observations. J Am Stat Assoc. 1958;53(282):457–81.

    Article  Google Scholar 

  48. Team RC. R: a language and environment for statistical computing. Vienna: R foundation for statistical Computing; 2016.

  49. Therneau T. A package for survival analysis in S. In: 2.38 EDN; 2015.

  50. Wickham H. Elegan graphics for data analysis. New York: Springer-Verlag; 2009.

    Google Scholar 

  51. Wickham H, Francois R. Dplyr: a grammar of data manipulation. In: 5.0 EDN; 2016.

  52. Gordon M. htmlTable: Advanced Tables for Markdown/HTML. In: 1.6 edn. R Package; 2016.

  53. Nair PM, Khawale PG. Role of therapeutic fasting in women's health: an overview. J Midlife Health. 2016;7(2):61–4.

    PubMed  PubMed Central  Google Scholar 

  54. Wahl D, Cogger VC, Solon-Biet SM, Waern RV, Gokarn R, Pulpitel T, Cabo R, Mattson MP, Raubenheimer D, Simpson SJ, et al. Nutritional strategies to optimise cognitive function in the aging brain. Ageing Res Rev. 2016.

  55. Longo VD, Panda S. Fasting, circadian rhythms, and time-restricted feeding in healthy lifespan. Cell Metab. 2016;23(6):1048–59.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

The authors kindly thank Jonathan Burgess for help with data auditing, James M. Lennon and Mary K Wilkinson for help with copyediting, and Dr. Jina Shah for useful comments.

Funding

This research was supported in part with a grant from the National Health Association. Grant number not provided. Additional support was provided by the TrueNorth Health Foundation. The funding bodies played no role in the design of the study or the collection, analysis, and interpretation of data.

Availability of data and materials

The dataset used and/or analyzed during the current study is available from the Dryad repository, https://doi.org/10.5061/dryad.6cg6j.

Author information

Authors and Affiliations

  1. AOMA Graduate School of Integrative Medicine, Austin, TX, 78745, USA

    John S. Finnell

  2. NoviSci, Durham, NC, USA

    Bradley C. Saul

  3. TrueNorth Health Center, Santa Rosa, CA, 95404, USA

    Alan C. Goldhamer

  4. TrueNorth Health Foundation, 1501 Pacific Avenue, Santa Rosa, CA, 95404, USA

    Alan C. Goldhamer & Toshia R. Myers

Authors
  1. John S. Finnell
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Bradley C. Saul
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Alan C. Goldhamer
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Toshia R. Myers
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

This study was conceived by JSF and ACG. The study was designed and data were managed and interpreted by JSF, BCS, and TRM. Data were abstracted by JSF. Data were analyzed by BCS. TRM wrote the first draft and all authors reviewed and edited later versions of this manuscript. All authors have seen and approved the final version.

Corresponding author

Correspondence to Toshia R. Myers.

Ethics declarations

Ethics approval and consent for participation

This study was approved by the Institutional Review Board (IRB) at the AOMA Graduate School of Integrative Medicine (AOMA: 2015–002). The research was conducted in accordance with the approved protocol and complied with the standards of the Declaration of Helsinki. This study involved a retrospective review of existing data that was de-identified prior to analysis and was granted a waiver of informed consent by the AOMA IRB.

Consent for publication

Not applicable for this study.

Competing interests

ACG is the director of the TrueNorth Health Center, president of the board of the TrueNorth Health Foundation, and member of the board of the National Health Association. He does not receive financial compensation for these roles. BCS and TRM are paid consultants for the TrueNorth Health Foundation, which is funded in part by the TrueNorth Health Center. JSF received funds from the National Health Association grant.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Additional file

Additional file 1:

Supplementary Methods. (DOCX 63 kb)

Rights and permissions

Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Finnell, J.S., Saul, B.C., Goldhamer, A.C. et al. Is fasting safe? A chart review of adverse events during medically supervised, water-only fasting. BMC Complement Altern Med 18, 67 (2018). https://doi.org/10.1186/s12906-018-2136-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12906-018-2136-6

Keywords

BMC Complementary Medicine and Therapies

ISSN: 2662-7671

Contact us