DOI: 10.5061/dryad.q2bvq83z8
title: Prolonged water‐only fasting followed by a whole‐plant‐food diet promotes fat‐free mass recovery and continued fat mass loss in adults with overweight or obesity

description: Conventional weight-loss strategies often result in inadequate fat loss,
 poor sustainability, and unintended lean mass loss. Prolonged water-only
 fasting followed by dietary change may offer an effective alternative, but
 its impact on body composition remains underexplored. This secondary
 analysis utilized dual-energy X-ray absorptiometry (DXA) to assess changes
 in fat-free mass (FFM), fat mass (FM), and bone mineral content (BMC) in
 adults [median (IQR) age: 62 (15) years] with overweight or obesity.
 Participants underwent a median (IQR) of 14 (6) days of water-only
 fasting, followed by 6 (3) days of food reintroduction with a
 whole-plant-food diet and a subsequent maintenance period of 45 (5) days.
 Study visits occurred at baseline and at the end of each period. At the
 end of fasting, FFM accounted for 74% of the total BW lost during fasting.
 However, at the follow-up visit, the median (IQR) percentage change in
 total BW, FFM, FM, and visceral adipose tissue (VAT) mass from baseline
 was -8.2 (5.2), -4.4 (5.6), -14.7 (8.9), and -15.8 (12.8) %, respectively.
 At follow-up, FM loss accounted for 67% of total BW lost. BMC remained
 unchanged across all study visits. This protocol produced sustained FM
 loss, specifically VAT mass, and FFM recovery, suggesting it may support
 effective weight management.
description: This study was a secondary analysis of data collected as part of
 a clinical trial (NCT04514146) that was approved by the TrueNorth Health
 Institutional Review Board in Santa Rosa, California (TNHF-2020-2VAT;
 April 2, 2020) and conducted according to the guidelines of the
 Declaration of Helsinki. The main study methods were previously
 published.<sup>31</sup> <strong>Study
 Details</strong> Participants were recruited from
 patients at a residential fasting center specializing in inpatient,
 medically supervised water-only fasting and whole-plant-food refeeding.
 Informed consent was obtained from all participants before enrollment and
 throughout the study. Forty participants were enrolled, of which 38
 completed the on-site fasting and food reintroduction protocol, and the 29
 participants presented here completed the full study
 protocol.<sup>31</sup> As previously described, eligibility
 included males and females aged 40–70 years with a BMI between 25–40 kg/m2
 and fasting glucose &lt;7 mmol/L and/or hemoglobin A1c &lt;7% who
 had independently elected to undergo a medically supervised water-only
 fast for at least 10 consecutive days followed by the standard food
 reintroduction period of no less than half the duration of the fast and
 who were previously approved to do so by a physician. The exclusion
 criteria were active malignancy, active inflammatory disorders, and stroke
 or heart attack within the last 90 days. Upon
 enrollment, participants attended study visits at baseline (BL), end of
 fasting (EOF), end of food reintroduction (EOR), and follow-up (FU), at
 approximately six weeks after the EOR. In addition to anthropometric,
 serology, clinical, demographic, and dietary adherence data collected as
 previously described,<sup>31</sup> DXA scans were performed
 during each study visit. At the EOR visit, participants were provided
 basic educational material on maintaining a whole-plant-food diet after
 returning to their home environment, but no other post-fast dietary
 support was provided between the EOR and FU visits. Dietary adherence was
 measured using a brief dietary screener specific to a whole-plant-food
 diet free of added salt, oil, and sugar.<sup>24</sup> At FU,
 participants reported increased consumption of whole-plant foods and
 decreased consumption of animal foods, dairy products, and added oil
 compared to BL.<sup>31</sup> All study data were collected and
 managed using REDCap electronic data capture tools hosted at TrueNorth
 Health Foundation.<sup>32</sup>
 <strong>Prolonged Water-only Fasting and Food
 Reintroduction Protocol</strong> The prolonged
 water-only fasting and food reintroduction protocol were detailed in the
 original publication.<sup>31</sup> The fasting and food
 reintroduction protocol was implemented by non-research medical personnel
 at a residential, fasting facility. Briefly, after being pre-screened
 before arrival and, if conditionally approved to water-only fast,
 potential participants were instructed to prepare by eating a diet of
 fresh fruits and raw or steamed vegetables <em>ad libitum</em>
 for two days prior to initiating the fast. While fasting, participants
 were instructed to consume a minimum of 1.2 liters of distilled water per
 day and limit their physical activity. Participants were monitored twice
 daily by medical personnel, and serology and urinalyses were measured once
 weekly and as indicated. The fast was terminated with an established food
 reintroduction protocol consisting of five phases of gradual food
 introduction beginning with vegetable broths and/or fruit and vegetable
 juices and ending with an <em>ad libitum</em> diet of cooked
 and raw whole-plant-foods free of added salt, oil, and sugar, with one
 phase for every 7-10 days of fasting lasting a minimum of half of the
 fasting duration.<sup>13</sup> Fasting lengths varied (see
 results below) but were no less than approximately 10 days, followed by a
 food reintroduction period of approximately five days.
 <strong>Clinical Measurements</strong>
 Clinical measurements were obtained at BL, EOF, EOR, and FU by
 research personnel as previously described.<sup>31</sup>
 Briefly, height was measured using a digital wall-mounted stadiometer. BW
 was measured using a digital body weight scale. BMI was calculated from
 height and weight.  AC was measured at the narrowest part of the
 participants’ midsection below the lowest palpable rib cage yet above the
 top of the hip/pelvic bones using a tension-sensitive, non-elastic tape.
 Resting SBP and DBP were measured in the morning after blood collection
 while in the seated position and after resting for five minutes using a
 digital blood pressure device.
 <strong>Dual-energy X-ray Absorptiometry (DXA)
 Measurements</strong> Participants underwent
 whole-body DXA scans (Horizon Wi [S/N 303354M], Hologic) at BL, EOF, EOR,
 and FU by certified technicians. Measurements were taken in the morning
 after drinking one glass of water. The interassay coefficients of
 variation reported for Horizon Wi were 0.50% and 0.98% for fat-free mass
 (FFM) and fat mass (FM), respectively, and 7.1%, 7.2%, and 2.83% for
 visceral adipose tissue (VAT) mass, volume, and area,
 respectively.<sup>33 34</sup>
 <strong>Statistical Analysis</strong>
 Data analysis was performed using R version
 4.3.2.<sup>35</sup> Medians, interquartile ranges (IQR),
 boxplots, histograms, and scatter plots were used to understand the data.
 The analysis used random intercept linear mixed-effects models with 95%
 confidence intervals (CI) where clinical parameters were the dependent
 variables, study visit the main independent variable, participant ID the
 grouping variable, and age and sex the control variables. The DXA and
 clinical measurements models were fitted in a Frequentist framework using
 the ‘lmerTest’ version 3.1.3 R package with confidence intervals obtained
 from ‘brooms.mixed’ version 0.2.9.4 while the dipstick urinalysis models
 were fitted in a Bayesian framework using the ‘brms’ 2.20.4 R package with
 the target average acceptance probability parameter, adapt_delta, set to
 0.99 due to warnings about divergent
 transitions.<sup>36-38</sup> Model diagnostics were assessed
 as previously described for models fitted with ‘lmerTest’ and
 ‘brms’.<sup>20 31</sup> When lmerTest model assumptions did
 not hold,<sup>39</sup> robust score
 equations<sup>40</sup> with the Satterthwaite degrees of
 freedom approximation<sup>41</sup> were employed. Complete
 case analysis was used to handle missing data. Regression coefficients
 were considered statistically significant when the 95% CI or 95% credible
 interval excluded 0.
description: # Prolonged water‐only fasting followed by a whole‐plant‐food diet
 promotes fat‐free mass recovery and continued fat mass loss in adults with
 overweight or obesity Dataset DOI:
 [10.5061/dryad.q2bvq83z8](10.5061/dryad.q2bvq83z8) Data Files Included *
 Prolonged_water‐only_fasting_dxa_data.csv This dataset accompanies the
 manuscript listed above and includes body composition measurements
 collected using a Hologic DXA scanner. The purpose of the dataset is to
 document changes in fat mass, lean mass, and other key metrics during
 prolonged water-only fasting and structured whole-plant-food refeeding in
 humans. Data are shared to support reproducibility and enable secondary
 analyses. **Experimental Summary** * **Sample Size**: N=29 * The
 `record_ID` field has been anonymized and the dataset does not contain any
 direct or indirect identifiers. * **Intervention:** Medically supervised
 prolonged water-only fasting (median duration: 14 days) followed by
 whole-plant-food refeeding (median duration: 6 days) and maintenance
 period (median duration: 46 days) * **Timepoints:** * **BL: baseline;
 before fasting** * **EOF: end of fast, before refeeding** * **EOR: end of
 refeeding, before leaving fasting center** * **FU: follow-up, six weeks
 after leaving the fasting center** * **Measurement tool:** Horizon Wi [S/N
 303354M], Hologic DXA system, operated by trained technicians in
 accordance with manufacturer protocols. | Variable | Unit | Description |
 | | :-------------------------- | :---------- |
 :------------------------------------ | - | | | Integer | Row Identifier |
 | | record\_id | Integer | Anonymized Unique Identifier | | |
 redcap\_event\_name | Categorical | Study Visit Timepoint | | |
 total\_weight | kg | total body weight | | | bone\_mineral\_content\_bmc |
 kg | bone mineral content | | | total\_lean\_mass | kg | total lean mass |
 | | lean\_mass | % | percent lean mass | | | total\_fat | kg | total fat
 mass | | | fat | % | percent fat mass | | | android\_fat\_mass | kg |
 android mass | | | gynoid\_fat\_mass | kg | gynoid mass | | |
 android\_gynoid\_ratio | Integer | ration of android mass to gynoid mass |
 | | total\_visceral\_fat | kg | estimated total visceral fat mass | | |
 est\_vat\_volume | m3 x 103  | estimated total visceral fat volume | | |
 est\_vat\_area | m2 x 102 | estimate total visceral fat area | | |
 lean\_mass\_index | kg/m2  | lean mass index | | | append\_lmi | kg/m2  |
 appendicular lean mass index | | | bone\_density | kg/m3  | bone density |
 | | Unit  | Description | | | | kg | kilogram | | | | % | percent | | | |
 m | meter | | | ## Human subjects data This study was a secondary analysis
 of data collected as part of a clinical trial (NCT04514146) that was
 approved by the TrueNorth Health Institutional Review Board in Santa Rosa,
 California (TNHF‐2020‐2VAT; April 2, 2020) and conducted according to the
 guidelines of the Declaration of Helsinki. All participants provided
 written, ongoing consent.