Reflecting On The 5:2 Diet & Intermittent Fasting

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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Mon Dec 09, 2019 7:00 am

The benefit reported was from the subjects (average BMI of 35) consuming 9% fewer calories which resulted in the weight loss & it’s related benefits, not from TRF having some magical benefit. No surprise.

Ten-Hour Time-Restricted Eating Reduces Weight, Blood Pressure, and Atherogenic Lipids in Patients with Metabolic Syndrome
Wilkinson et al., 2020, Cell Metabolism 31, 1–13 January 7, 2020 a 2019 Elsevier Inc.


In animal models, time-restricted feeding (TRF) can prevent and reverse aspects of metabolic diseases. Time-restricted eating (TRE) in human pilot studies reduces the risks of metabolic diseases in otherwise healthy individuals. However, patients with diag- nosed metabolic syndrome often undergo pharma- cotherapy, and it has never been tested whether TRE can act synergistically with pharmacotherapy in animal models or humans. In a single-arm, paired-sample trial, 19 participants with metabolic syndrome and a baseline mean daily eating window of R14 h, the majority of whom were on a statin and/or antihypertensive therapy, underwent 10 h of TRE (all dietary intake within a consistent self- selected 10 h window) for 12 weeks. We found this TRE intervention improves cardiometabolic health for patients with metabolic syndrome receiving stan- dard medical care including high rates of statin and anti-hypertensive use. TRE is a potentially powerful lifestyle intervention that can be added to standard medical practice to treat metabolic syndrome
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Sun Dec 22, 2019 4:53 pm

A review of a popular trend in Meal Timing

Are large dinners associated with excess weight, and does eating a smaller dinner achieve greater weight loss? A systematic review and meta-analysis
Access Volume 118, Issue 8 28 October 2017 , pp. 616-628
Published online by Cambridge University Press: 02 October 2017


There are suggestions that large evening meals are associated with greater BMI. This study reviewed systematically the association between evening energy intake and weight in adults and aimed to determine whether reducing evening intake achieves weight loss. Databases searched were MEDLINE, PubMed, Cinahl, Web of Science, Cochrane Library of Clinical Trials, EMBASE and SCOPUS. Eligible observational studies investigated the relationship between BMI and evening energy intake. Eligible intervention trials compared weight change between groups where the proportion of evening intake was manipulated. Evening intake was defined as energy consumed during a certain time – for example 18.00–21.00 hours – or self-defined meal slots – that is ‘dinner’. The search yielded 121 full texts that were reviewed for eligibility by two independent reviewers. In all, ten observational studies and eight clinical trials were included in the systematic review with four and five included in the meta-analyses, respectively. Four observational studies showed a positive association between large evening intake and BMI, five showed no association and one showed an inverse relationship. The meta-analysis of observational studies showed a non-significant trend between BMI and evening intake (P=0·06). The meta-analysis of intervention trials showed no difference in weight change between small and large dinner groups (−0·89 kg; 95 % CI −2·52, 0·75, P=0·29). This analysis was limited by significant heterogeneity, and many trials had an unknown or high risk of bias. Recommendations to reduce evening intake for weight loss cannot be substantiated by clinical evidence, and more well-controlled intervention trials are needed.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Fri Jan 17, 2020 7:02 am

While the abstract says the IF groups did as well, the study proves different. This was a 2 year study. While the results are not spectacular, continuous energy restriction (CER) did best over the 2 types of fasting. While the WOWO group had a slight edge during the first few weeks, CER was the clear winner through out the rest of the year and at 12 months & at the 24 month follow up. (See the charts attached).

Impact of intermittent vs. continuous energy restriction on weight and cardiometabolic factors: a 12-month follow-up
International Journal of Obesity

Background and objective Intermittent energy restriction continues to gain popularity as a weight loss strategy; however, data assessing it’s long-term viability is limited. The objective of this study was to follow up with participants 12 months after they had completed a 12-month dietary intervention trial involving continuous energy restriction and two forms of intermittent energy restriction; a week-on-week-off energy restriction and a 5:2 programme, assessing long-term changes on weight, body composition, blood lipids and glucose.

Subjects and methods
109 overweight and obese adults, aged 18–72 years, attended a 12-month follow-up after completing a 12-month dietary intervention involving three groups: continuous energy restriction (1000kcal/day for women and 1200 kcal/day for men), week-on-week-off energy restriction (alternating between the same energy restriction as the con- tinuous group for one week and one week of habitual diet), or 5:2 (500 kcal/day on modified fast days each week for women and 600 kcal/day for men). The primary outcome was weight change at 24 months from baseline, with secondary outcomes of change in body composition, blood lipids and glucose.

For the 109 individuals who completed the 12-month follow-up (82 female, 15 male, mean BMI 33 kg/m2), weight decreased over time with no differences between week-on and week-off and continuous energy restriction or 5:2 and continuous energy restriction with −4.5 ± 4.9 kg for continuous energy restriction, −2.8 ± 6.5 kg for week-on, week-off and −3.5 ± 5.1 kg for 5:2. Total cholesterol reduced over time and glucose, HDL, LDL and triglycerides were unchanged.

Discussion and conclusion Intermittent energy restriction was as successful in achieving modest weight loss over a 24- month period as continuous energy restriction.

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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Mon Sep 28, 2020 12:47 pm

No benefit/difference but greater muscle loss, and decrease in activity and lower adherence

Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity. The TREAT Randomized Clinical Trial
JAMA Intern Med.
Published online September 28, 2020.

Full Text (attached below) ... .29942.pdf

Key Points
Question: What is the effect of time-restricted eating on weight loss and metabolic health in patients with overweight and obesity?

Findings: In this prospective randomized clinical trial that included 116 adults with overweight or obesity, time-restricted eating was associated with a modest decrease (1.17%) in weight that was not significantly different from the decrease in the control group (0.75%).

Meaning: Time-restricted eating did not confer weight loss or cardiometabolic benefits in this study.


Importance: The efficacy and safety of time-restricted eating have not been explored in large randomized clinical trials.

Objective: To determine the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers.

Interventions: Participants were randomized such that the consistent meal timing (CMT) group was instructed to eat 3 structured meals per day, and the time-restricted eating (TRE) group was instructed to eat ad libitum from 12:00 pm until 8:00 pm and completely abstain from caloric intake from 8:00 pm until 12:00 pm the following day.

Design, Setting, and Participants: This 12-week randomized clinical trial including men and women aged 18 to 64 years with a body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) of 27 to 43 was conducted on a custom mobile study application. Participants received a Bluetooth scale. Participants lived anywhere in the United States, with a subset of 50 participants living near San Francisco, California, who underwent in-person testing.

Main Outcomes and Measures: The primary outcome was weight loss. Secondary outcomes from the in-person cohort included changes in weight, fat mass, lean mass, fasting insulin, fasting glucose, hemoglobin A1c levels, estimated energy intake, total energy expenditure, and resting energy expenditure.

Results: Overall, 116 participants (mean [SD] age, 46.5 [10.5] years; 70 [60.3%] men) were included in the study. There was a significant decrease in weight in the TRE (−0.94 kg; 95% CI, −1.68 to −0.20; P = .01), but no significant change in the CMT group (−0.68 kg; 95% CI, -1.41 to 0.05, P = .07) or between groups (−0.26 kg; 95% CI, −1.30 to 0.78; P = .63). In the in-person cohort (n = 25 TRE, n = 25 CMT), there was a significant within-group decrease in weight in the TRE group (−1.70 kg; 95% CI, −2.56 to −0.83; P < .001). There was also a significant difference in appendicular lean mass index between groups (−0.16 kg/m2; 95% CI, −0.27 to −0.05; P = .005). There were no significant changes in any of the other secondary outcomes within or between groups. There were no differences in estimated energy intake between groups.

Conclusions and Relevance: Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating

From the study...

On Adherence...

“Self-reported adherence to the diets was 1002 of 1088 (92.1%) in the CMT group (did not miss any meals) and 1128 of 1351 (83.50%) in the TRE group (ate only within the 8-hour win- dow) (Figure 2A).”

On Lean Mass....

“In analysis of secondary outcomes, we found a signifi- cant reduction in lean mass in the TRE group. In the in- person cohort, the average weight loss in the TRE group was 1.70 kg. Of this, 1.10 kg (approximately 65% of weight lost) was lean mass; only 0.51 kg of weight loss was fat mass. Loss of lean mass during weight loss typically accounts for 20% to 30% of total weight loss.16-22 The proportion of lean mass loss in this study (approximately 65%) far exceeds the normal range of 20% to 30%.22 In addition, there was a highly significant be- tween-group difference in ALM. Appendicular lean mass is cor- related with nutritional and physical status, and reduced ALM can lead to weakness, disability, and impaired quality of life.23-26 This serves as a caution for patient populations at risk for sarcopenia because TRE could exacerbate muscle loss.27 Finally, the extent of lean mass loss during weight loss has been positively correlated with weight regain.”

On Activity

“The Oura ring data also revealed a significant reduction in daily movement in the TRE group (−2102.14 au; 95% CI, −3162.54 au to −1041.73 au; P < .001) and between groups (−1673.44 au; 95% CI, −3211.11 au to −135.7 au; P = .03) but not in the CMT group (−428.70 au; 95% CI, −1542.25 au to 684.85 au; P = .45). There was a significant decrease in step count in the TRE group (−2498.89 steps; 95% CI, −3939.91 to −1057.88; P < .001) and between groups (−2241.41 steps; 95% CI, −4320.51 to −162.31; P = .04) but not in the CMT group (−257.48 steps; 95% CI, −1756.20 to 1241.23; P = .74). The correlation be- tween change in step count and change in TEE was 0.52 in the TRE group and 0.03 in the CMT group, but the 2 correlations did not differ significantly (eFigure 4 in Supplement 3).”
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