Reflecting On The 5:2 Diet & Intermittent Fasting

A place to get your questions answered from McDougall staff dietitian, Jeff Novick, MS, RDN.

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

Postby JeffN » Thu Aug 10, 2017 3:01 pm

Again, no better

Is two days of intermittent energy restriction per week a feasible weight loss approach in obese males? A randomised pilot study.
Conley M, Le Fevre L, Haywood C, Proietto J.
Nutr Diet. 2017 Aug 9. doi: 10.1111/1747-0080.12372. [Epub ahead of print]
PMID: 28791787

Abstract

AIM:
The 5:2 diet (two non-consecutive days of 2460 KJ (600 calories) and 5 days of ad libitum eating per week) is becoming increasingly popular. This pilot study aimed to determine whether the 5:2 diet can achieve ≥5% weight loss and greater improvements in weight and biochemical markers than a standard energy-restricted diet (SERD) in obese male war veterans.

METHODS:
A total of 24 participants were randomised to consume either the 5:2 diet or a SERD (2050 KJ (500 calorie) reduction per day) for 6 months. Weight, waist circumference (WC), fasting blood glucose, blood lipids, blood pressure and dietary intake were measured at baseline, 3 and 6 months by a blinded investigator.

RESULTS:
After 6 months, participants in both groups significantly reduced body weight (P = <0.001), WC (P = <0.001) and systolic blood pressure (P = 0.001). Mean weight loss was 5.3 ± 3.0 kg (5.5 ± 3.2%) for the 5:2 group and 5.5 ± 4.3 kg (5.4 ± 4.2%) for the SERD group. Mean WC reduction for the 5:2 group was 8.0 ± 4.5 and 6.4 ± 5.8 cm for the SERD group. There was no significant difference in the amount of weight loss or WC reduction between diet groups. There was no significant change in diastolic blood pressure, fasting blood glucose or blood lipids in either dietary group.

CONCLUSIONS:
Results suggest that the 5:2 diet is a successful but not superior weight loss approach in male war veterans when compared to a SERD. Future research is needed to determine the long-term effectiveness of the 5:2 diet and its effectiveness in other population groups.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Fri Oct 06, 2017 6:57 am

Again, no better with little evidence for it.

Short-term intermittent energy restriction interventions for weight management: a systematic review and meta-analysis.
Harris L, McGarty A, Hutchison L, Ells L, Hankey C.
Obes Rev. 2017 Oct 4. doi: 10.1111/obr.12593. [Epub ahead of print] Review.
PMID: 28975722

http://onlinelibrary.wiley.com/doi/10.1 ... 12593/full

Abstract
This systematic review synthesized the available evidence on the effect of short-term periods of intermittent energy restriction (weekly intermittent energy restriction; ≥7-d energy restriction) in comparison with usual care (daily continuous energy restriction), in the treatment of overweight and obesity in adults. Six electronic databases were searched from inception to October 2016. Only randomized controlled trials of interventions (≥12 weeks) in adults with overweight and obesity were included. Five studies were included in this review. Weekly intermittent energy restriction periods ranged from an energy intake between 1757 and 6276 kJ/d-1 . The mean duration of the interventions was 26 (range 14 to 48) weeks. Meta-analysis demonstrated no significant difference in weight loss between weekly intermittent energy restriction and continuous energy restriction post-intervention (weighted mean difference: -1.36 [-3.23, 0.51], p = 0.15) and at follow-up (weighted mean difference: -0.82 [-3.76, 2.11], p = 0.58). Both interventions achieved comparable weight loss of >5 kg and therefore were associated with clinical benefits to health. The findings support the use of weekly intermittent energy restriction as an alternative option for the treatment of obesity. Currently, there is insufficient evidence to support the long-term sustainable effects of weekly intermittent energy restriction on weight management.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Wed Dec 06, 2017 11:44 am

Intermittent fasting and cardiovascular disease: current evidence and unresolved questions.
Future Cardiol. 2017 Dec 4.
doi: 10.2217/fca-2017-0038.
[Epub ahead of print]
PMID: 29199853

Abstract
Intermittent fasting has produced a variety of beneficial health effects in animal models, although high-quality research in humans has been limited. This special report examines current evidences for intermittent fasting in humans, discusses issues that require further examination, and recommends new research that can improve the knowledge base in this emerging research area. While potentially useful for health improvement, intermittent fasting requires further study prior to widespread implementation for health purposes. Randomized, longer-term studies are needed to determine whether using intermittent fasting as a lifestyle rather than a diet is feasible and beneficial for the health of some members of the human population.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Thu Dec 21, 2017 4:16 pm

Again, no difference or benefit

Effects of alternate-day fasting or daily calorie restriction on body composition, fat distribution, and circulating adipokines: Secondary analysis of a randomized controlled trial.
Trepanowski JF, Kroeger CM, Barnosky A, Klempel M, Bhutani S, Hoddy KK, Rood J, Ravussin E, Varady KA.
Clin Nutr. 2017 Dec 5. pii: S0261-5614(17)31416-4. doi: 10.1016/j.clnu.2017.11.018. [Epub ahead of print]
PMID: 29258678

http://www.clinicalnutritionjournal.com ... 61-5614(17)31416-4/abstract

Abstract
BACKGROUND & AIMS:
Indirect comparisons suggest that alternate-day fasting (ADF) may produce greater improvements in body composition, fat distribution, and/or the adipokine profile compared to daily calorie restriction (CR), but this has not been tested directly. In a pre-planned secondary analysis of a randomized controlled trial, we compared changes in the VAT:SAT ratio, FFM:total mass ratio, and the adipokine profile between ADF and CR.

METHODS:
Overweight and obese participants (n = 100) were randomized to 1) ADF (alternating every 24-h between consuming 25% or 125% of energy needs); 2) CR (consuming 75% of needs every day); or 3) control (consuming 100% of needs every day) for 24 wk.

RESULTS:
The VAT:SAT ratio did not change in any group. The FFM:total mass ratio increased in both ADF (0.03 ± 0.00) and CR (0.03 ± 0.01) compared to the control group (P < 0.01), with no differences between the intervention groups. Circulating leptin decreased in both the ADF group (-18 ± 6%) and CR group (-31 ± 10%) relative to the control group (P < 0.05), with no differences between the intervention groups. Circulating levels of adiponectin, resistin, IL-6, and TNF-α did not change in either intervention group relative to the control group.

CONCLUSION:
ADF and CR similarly improve the FFM:total mass ratio and reduce leptin after a 24-wk intervention.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Fri Feb 09, 2018 12:14 pm

From Cochrane

Once again, no better


Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis.
Harris L, Hamilton S, Azevedo LB, Olajide J, De Brún C, Waller G, Whittaker V, Sharp T, Lean M, Hankey C, Ells L.
JBI Database System Rev Implement Rep. 2018 Feb;16(2):507-547. doi: 10.11124/JBISRIR-2016-003248.
PMID: 29419624

Abstract
OBJECTIVE:
To examine the effectiveness of intermittent energy restriction in the treatment for overweight and obesity in adults, when compared to usual care treatment or no treatment.

INTRODUCTION:
Intermittent energy restriction encompasses dietary approaches including intermittent fasting, alternate day fasting, and fasting for two days per week. Despite the recent popularity of intermittent energy restriction and associated weight loss claims, the supporting evidence base is limited.

INCLUSION CRITERIA:
This review included overweight or obese (BMI ≥25 kg/m) adults (≥18 years). Intermittent energy restriction was defined as consumption of ≤800 kcal on at least one day, but no more than six days per week. Intermittent energy restriction interventions were compared to no treatment (ad libitum diet) or usual care (continuous energy restriction ∼25% of recommended energy intake). Included interventions had a minimum duration of 12 weeks from baseline to post outcome measurements. The types of studies included were randomized and pseudo-randomized controlled trials. The primary outcome of this review was change in body weight. Secondary outcomes included: i) anthropometric outcomes (change in BMI, waist circumference, fat mass, fat free mass); ii) cardio-metabolic outcomes (change in blood glucose and insulin, lipoprotein profiles and blood pressure); and iii) lifestyle outcomes: diet, physical activity, quality of life and adverse events.

METHODS:
A systematic search was conducted from database inception to November 2015. The following electronic databases were searched: MEDLINE, Embase, CINAHL, Cochrane Library, ClinicalTrials.gov, ISRCTN registry, and anzctr.org.au for English language published studies, protocols and trials. Two independent reviewers evaluated the methodological quality of included studies using the standardized critical appraisal instruments from the Joanna Briggs Institute. Data were extracted from papers included in the review by two independent reviewers using the standardized data extraction tool from the Joanna Briggs Institute. Effect sizes were expressed as weighted mean differences and their 95% confidence intervals were calculated for meta-analyses.

RESULTS:
Six studies were included in this review. The intermittent energy restriction regimens varied across studies and included alternate day fasting, fasting for two days, and up to four days per week. The duration of studies ranged from three to 12 months. Four studies included continuous energy restriction as a comparator intervention and two studies included a no treatment control intervention. Meta-analyses showed that intermittent energy restriction was more effective than no treatment for weight loss (-4.14 kg; 95% CI -6.30 kg to -1.99 kg; p ≤ 0.001). Although both treatment interventions achieved similar changes in body weight (approximately 7 kg), the pooled estimate for studies that investigated the effect of intermittent energy restriction in comparison to continuous energy restriction revealed no significant difference in weight loss (-1.03 kg; 95% CI -2.46 kg to 0.40 kg; p = 0.156).

CONCLUSIONS:
Intermittent energy restriction may be an effective strategy for the treatment of overweight and obesity. Intermittent energy restriction was comparable to continuous energy restriction for short term weight loss in overweight and obese adults. Intermittent energy restriction was shown to be more effective than no treatment, however, this should be interpreted cautiously due to the small number of studies and future research is warranted to confirm the findings of this review.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Sat Apr 28, 2018 12:05 pm

Intermittent Fasting: Is the Wait Worth the Weight?
Stockman MC, Thomas D, Burke J, Apovian CM.
Curr Obes Rep. 2018 Apr 26. doi: 10.1007/s13679-018-0308-9. [Epub ahead of print] Review.
PMID: 29700718

Abstract

PURPOSE OF REVIEW:
We review the underlying mechanisms and potential benefits of intermittent fasting (IF) from animal models and recent clinical trials.

RECENT FINDINGS:
Numerous variations of IF exist, and study protocols vary greatly in their interpretations of this weight loss trend. Most human IF studies result in minimal weight loss and marginal improvements in metabolic biomarkers, though outcomes vary. Some animal models have found that IF reduces oxidative stress, improves cognition, and delays aging. Additionally, IF has anti-inflammatory effects, promotes autophagy, and benefits the gut microbiome. The benefit-to-harm ratio varies by model, IF protocol, age at initiation, and duration. We provide an integrated perspective on potential benefits of IF as well as key areas for future investigation. In clinical trials, caloric restriction and IF result in similar degrees of weight loss and improvement in insulin sensitivity. Although these data suggest that IF may be a promising weight loss method, IF trials have been of moderate sample size and limited duration. More rigorous research is needed.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Sun May 20, 2018 6:10 am

This was presented at the meeting and not published yet. I’ll link the actual paper when published. (Note: something similar has been seen in some of the “extreme” CR practitioners)

In Health
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Fasting diets may raise risk of diabetes, researchers warn

New study also suggests regimes that include intermittent fasting may cause other long-term health problems
Robin McKieSun 20 May 2018 02.00 EDT

https://www.theguardian.com/society/201 ... f-diabetes

Fasting every other day to lose weight could have damaging side effects. That is the conclusion of a group of scientists speaking this weekend at the European Society of Endocrinology’s annual meeting.

Their findings suggest that fasting-based diets may impair the action of sugar-regulating hormone insulin, and lead to increased risk of diabetes. Care should be taken before starting such programmes, say researchers.

Ana Bonassa, whose team from the University of São Paulo in Brazil carried out the study, said: “This is the first study to show that, despite weight loss, intermittent fasting diets may actually damage the pancreas and affect insulin function in normal healthy individuals, which could lead to diabetes and serious health issues.”

In recent years intermittent fasting diets have gained popularity. Participants fast for two days out of seven, or on alternate days. However, evidence of their success has been contradictory and there is debate among doctors about their potential to trigger harmful long-term effects.

Previous research has also shown that short-term fasting can produce molecules called free radicals, highly reactive chemicals that can cause damage to cells in the body and which may be associated with impaired organ function, cancer risk and accelerated ageing.

The São Paulo researchers examined the effects of fasting every other day on the bodyweight, free radical levels and insulin function of normal adult rats over three months. Although the rats’ bodyweight and food intake decreased as expected, the amount of fat tissue in their abdomen actually increased. In addition, cells of the pancreas that release insulin showed damage, while the presence of increased levels of free radicals and markers of insulin resistance were also detected.

The results also suggest that in the long-term harm may be caused and that more investigation is needed to assess how people may be affected, particularly those with existing metabolic issues.

“We should consider that overweight or obese people who opt for intermittent fasting diets may already have insulin resistance, so although this diet may lead to early, rapid weight loss, in the long-term there could be potentially serious damaging effects to their health, such as the development of type 2 diabetes,” added Bonassa.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Mon May 21, 2018 10:43 am

Remember, one of the key tenets of the program is to eat when hungry until comfortably full. If intermittent fasting increases hunger and other side effects, it is not going to work over the long term. Hunger is a powerful built in drive like respiration and thirst.



Effect of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk: A randomized 1-year trial.
Nutr Metab Cardiovasc Dis. 2018 Mar 29. pii: S0939-4753(18)30100-5.
doi: 10.1016/j.numecd.2018.03.009. [Epub ahead of print]
PMID: 29778565

https://www.nmcd-journal.com/article/S0939-4753(18)30100-5/fulltext

Abstract

BACKGROUND & AIMS:
Long-term adherence to conventional weight-loss diets is limited while intermittent fasting has risen in popularity. We compared the effects of intermittent versus continuous energy restriction on weight loss, maintenance and cardiometabolic risk factors in adults with abdominal obesity and ≥1 additional component of metabolic syndrome.

METHODS & RESULTS:
In total 112 participants (men [50%] and women [50%]) aged 21-70 years with BMI 30-45 kg/m2 (mean 35.2 [SD 3.7]) were randomized to intermittent or continuous energy restriction. A 6-month weight-loss phase including 10 visits with dieticians was followed by a 6-month maintenance phase without additional face-to-face counselling. The intermittent energy restriction group was advised to consume 400/600 kcal (female/male) on two non-consecutive days. Based on dietary records both groups reduced energy intake by ∼26-28%. Weight loss was similar among participants in the intermittent and continuous energy restriction groups (8.0 kg [SD 6.5] versus 9.0 kg [SD 7.1]; p = 0.6). There were favorable improvements in waist circumference, blood pressure, triglycerides and HDL-cholesterol with no difference between groups. Weight regain was minimal and similar between the intermittent and continuous energy restriction groups (1.1 kg [SD 3.8] versus 0.4 kg [SD 4.0]; p = 0.6). Intermittent restriction participants reported higher hunger scores than continuous restriction participants on a subjective numeric rating scale (4.7 [SD 2.2] vs 3.6 [SD 2.2]; p = 0.002).

CONCLUSIONS:
Both intermittent and continuous energy restriction resulted in similar weight loss, maintenance and improvements in cardiovascular risk factors after one year. However, feelings of hunger may be more pronounced during intermittent energy restriction.

From the Full Test

Adverse Effects - - CER // IF
Dizziness - - 3% // 11%
Mild Headache - - 5% // 20%
Nausea - - 2% // 6%
Sleep Disturbance - - 0% // 2%

CER = Cotinuous Energy Restriction
IF = Intermittent Fasting
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Mon May 21, 2018 10:59 am

JeffN wrote:Remember, one of the key tenets of the program is to eat when hungry until comfortably full. Having to restrict to increase hunger, is not going to work over the long term. Hunger is a powerful built in drive like respiration and thirst.


In a recent discussion on these latest IF studies, my long-time colleague Jay Kenney, PhD, RDN, said this,....

“Nutrition science is about what to eat. It gets complicated when that focus shifts form what to eat to how much to eat and/or when to eat. Knowing when to eat is simple and knowing when to stop eating is simple. Eat when you are hungry and stop when you are comfortably full (not stuffed). Calorie restriction (CR) & IF (and other forms of time restricted eating) complicates when (and sometimes also how much) one should be eating because it proclaims you should not eat even when you are hungry or you must stop eating before being satiated. CR as a means of weight control or as an attempt to induce longevity or slow aging complicates how much one should eat. If one understand how different foods impact disease risk factors and satiety/kcal, one can change what is being consumed in order to treat and prevent disease and maintain a healthy body weight and likely live a longer and healthier life.. ”
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Sun Nov 25, 2018 10:51 am

Again, no difference. Randomized trial.

Effect of intermittent compared to continuous energy restriction on weight loss and weight maintenance after 12 months in healthy overweight or obese adults.
Headland ML, Clifton PM, Keogh JB.
Int J Obes (Lond). 2018 Nov 23.
doi: 10.1038/s41366-018-0247-2. [Epub ahead of print]
PMID: 30470804

Abstract

BACKGROUND AND OBJECTIVE:
Intermittent energy restriction (IER) is an alternative to continuous energy restriction (CER) for weight loss. There are few long-term trials comparing efficacy of these methods. The objective was to compare the effects of CER to two forms of IER; a week-on-week-off energy restriction and a 5:2 program, during which participants restricted their energy intake severely for 2 days and ate as usual for 5 days, on weight loss, body composition, blood lipids, and glucose.

SUBJECTS AND METHODS:
A one-year randomized parallel trial was conducted at the University of South Australia, Adelaide, Australia. Participants were 332 overweight and obese adults, ages 18-72 years, who were randomized to 1 of 3 groups: CER (4200 kJ/day for women and 5040 kJ/day for men), week-on-week-off energy restriction (alternating between the same energy restriction as the continuous group for one week and one week of habitual diet), or 5:2 (2100 kJ/day on modified fast days each week for women and 2520 kJ/day for men, the 2 days of energy restriction could be consecutive or non-consecutive). Primary outcome was weight loss, and secondary outcomes were changes in body composition, blood lipids, and glucose.

RESULTS:
For the 146 individuals who completed the study (124 female, 22 male, mean BMI 33 kg/m2) mean weight loss, and body fat loss at 12 months was similar in the three intervention groups, -6.6 kg for CER, -5.1 kg for the week-on, week-off and -5.0 kg for 5:2 (p = 0.2 time by diet). Discontinuation rates were not different (p = 0.4). HDL-cholesterol rose (7%) and triglycerides decreased (13%) at 12 months with no differences between groups. No changes were seen for fasting glucose or LDL-cholesterol.

DISCUSSION AND CONCLUSION:
The two forms of IER were not statistically different for weight loss, body composition, and cardiometabolic risk factors compared to CER.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Tue Nov 27, 2018 10:57 am

Another RCT and again, no difference. However, the IF subjects reported "feeling cold, tired, and having
mild headaches, mild cognitive impairments, i.e., lack of concentration, on energy-restricted days"


Effects of intermittent and continuous calorie restriction on body weight and metabolism over 50 wk: a randomized controlled trial.
Am J Clin Nutr. 2018 Nov 1;108(5):933-945. doi: 10.1093/ajcn/nqy196.
PMID: 30475957

Abstract

BACKGROUND:
Although preliminary evidence suggests that intermittent calorie restriction (ICR) exerts stronger effects on metabolic parameters, which may link obesity and major chronic diseases, compared with continuous calorie restriction (CCR), there is a lack of well-powered intervention studies.

OBJECTIVE:
We conducted a randomized controlled trial to test whether ICR, operationalized as the "5:2 diet," has stronger effects on adipose tissue gene expression, anthropometric and body composition measures, and circulating metabolic biomarkers than CCR and a control regimen.

DESIGN:
One hundred and fifty overweight and obese nonsmokers [body mass index (kg/m2) ≥25 to <40, 50% women], aged 35-65 y, were randomly assigned to an ICR group (5 d without energy restriction and 2 d with 75% energy deficit, net weekly energy deficit ∼20%), a CCR group (daily energy deficit ∼20%), or a control group (no advice to restrict energy) and participated in a 12-wk intervention phase, a 12-wk maintenance phase, and a 26-wk follow-up phase.

RESULTS:
Loge relative weight change over the intervention phase was -7.1% ± 0.7% (mean ± SEM) with ICR, -5.2% ± 0.6% with CCR, and -3.3% ± 0.6% with the control regimen (Poverall < 0.001, PICR vs. CCR = 0.053). Despite slightly greater weight loss with ICR than with CCR, there were no significant differences between the groups in the expression of 82 preselected genes in adipose tissue implicated in pathways linking obesity to chronic diseases. At the final follow-up assessment (week 50), weight loss was -5.2% ± 1.2% with ICR, -4.9% ± 1.1% with CCR, and -1.7% ± 0.8% with the control regimen (Poverall = 0.01, PICR vs. CCR = 0.89). These effects were paralleled by proportional changes in visceral and subcutaneous adipose tissue volumes. There were no significant differences between ICR and CCR regarding various circulating metabolic biomarkers.

CONCLUSION:
Our results on the effects of the "5:2 diet" indicate that ICR may be equivalent but not superior to CCR for weight reduction and prevention of metabolic diseases.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Fri Dec 21, 2018 4:05 pm

Very short-term small study but none the less, here it is.. the only real (but minor) benefit to IF is if the IF group eats less and even then, didn’t do anything special metabolically.

"This study demonstrates that IF approaches using repeated 24-hour fasts improve metabolic health when in energy deficit but not when in energy balance."

It doesn’t look like they tracked adverse effects, which has always been higher in the IF groups.

In Health
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Effects of Intermittent Versus Continuous Energy Intakes on Insulin Sensitivity and Metabolic Risk in Women with Overweight.
Obesity (Silver Spring). 2019 Jan;27(1):50-58. doi: 10.1002/oby.22345.
PMID: 30569640
https://onlinelibrary.wiley.com/doi/ful ... /oby.22345

Abstract
OBJECTIVE:
This study aimed to compare intermittent fasting (IF) versus continuous energy intakes at 100% or 70% of calculated energy requirements on insulin sensitivity, cardiometabolic risk, body weight, and composition.

METHODS:
Women with overweight (n = 88; 50 ± 1 years, BMI 32.3 ± 0.5 kg/m2 ) were randomized to one of four diets (IF70, IF100, dietary restriction [DR70], or control) in a 2:2:2:1 ratio for 8 weeks. IF groups fasted for 24 hours after breakfast on three nonconsecutive days per week. All foods were provided and diets matched for macronutrient composition (35% fat, 15% protein, 50% carbohydrate). Insulin sensitivity by hyperinsulinemic-euglycemic clamp, weight, body composition, and plasma markers were assessed following a "fed" day (12-hour fast) and a 24-hour fast (IF only).

RESULTS:
IF70 displayed greater reductions in weight, fat mass, total- and low-density lipoprotein cholesterol, and nonesterified fatty acids compared with DR70 and IF100 (all P ≤ 0.05). IF100 lost more weight and fat than control. However, fasting insulin was increased. There were no group differences in insulin sensitivity by clamp; however, a 24-hour fast transiently reduced insulin sensitivity.

CONCLUSIONS:
When prescribed at matched energy restriction, IF reduced weight and fat mass and improved total and low-density lipoprotein cholesterol more than DR. IF prescribed in energy balance did not improve health compared with other groups, despite modest weight loss.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Thu Dec 27, 2018 11:49 am

no difference


Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials.
Cioffi I, Evangelista A, Ponzo V, Ciccone G, Soldati L, Santarpia L, Contaldo F, Pasanisi F, Ghigo E, Bo S.
J Transl Med. 2018 Dec 24;16(1):371. doi: 10.1186/s12967-018-1748-4. Review.
PMID: 30583725
https://translational-medicine.biomedce ... 018-1748-4
https://translational-medicine.biomedce ... 018-1748-4

Abstract

BACKGROUND:
This systematic review and meta-analysis summarized the most recent evidence on the efficacy of intermittent energy restriction (IER) versus continuous energy restriction on weight-loss, body composition, blood pressure and other cardiometabolic risk factors.

METHODS:
Randomized controlled trials were systematically searched from MEDLINE, Cochrane Library, TRIP databases, EMBASE and CINAHL until May 2018. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI).


RESULTS:
Eleven trials were included (duration range 8-24 weeks). All selected intermittent regimens provided ≤ 25% of daily energy needs on "fast" days but differed for type of regimen (5:2 or other regimens) and/or dietary instructions given on the "feed" days (ad libitum energy versus balanced energy consumption). The intermittent approach determined a comparable weight-loss (WMD: - 0.61 kg; 95% CI - 1.70 to 0.47; p = 0.87) or percent weight loss (WMD: - 0.38%, - 1.16 to 0.40; p = 0.34) when compared to the continuous approach. A slight reduction in fasting insulin concentrations was evident with IER regimens (WMD = - 0.89 µU/mL; - 1.56 to - 0.22; p = 0.009), but the clinical relevance of this result is uncertain. No between-arms differences in the other variables were found.

CONCLUSIONS:
Both intermittent and continuous energy restriction achieved a comparable effect in promoting weight-loss and metabolic improvements. Long-term trials are needed to draw definitive conclusions.
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Wed Nov 06, 2019 6:29 am

Again, no real difference, greater adverse effects


Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss
Nutrients 2019, 11(10), 2442; https://doi.org/10.3390/nu11102442
Received: 20 August 2019 / Accepted: 5 October 2019 / Published: 14 October 2019

https://www.mdpi.com/2072-6643/11/10/2442/htm

Abstract: The current obesity epidemic is staggering in terms of its magnitude and public health impact. Current guidelines recommend continuous energy restriction (CER) along with a comprehensive lifestyle intervention as the cornerstone of obesity treatment, yet this approach produces modest weight loss on average. Recently, there has been increased interest in identifying alternative dietary weight loss strategies that involve restricting energy intake to certain periods of the day or prolonging the fasting interval between meals (i.e., intermittent energy restriction, IER). These strategies include intermittent fasting (IMF; >60% energy restriction on 2–3 days per week, or on alternate days) and time-restricted feeding (TRF; limiting the daily period of food intake to 8–10 h or less on most days of the week). Here, we summarize the current evidence for IER regimens as treatments for overweight and obesity. Specifically, we review randomized trials of ≥8 weeks in duration performed in adults with overweight or obesity (BMI ≥ 25 kg/m2) in which an IER paradigm (IMF or TRF) was compared to CER, with the primary outcome being weight loss. Overall, the available evidence suggests that IER paradigms produce equivalent weight loss when compared to CER, with 9 out of 11 studies reviewed showing no differences between groups in weight or body fat loss.

From the study, on the IF groups

- (They) reported more hunger, more adverse events, less favorable changes in diet nutritional composition and eating behavior, and greater measured weight regain than participants in the CER group.

- 57% felt that they could not have maintained the TRF protocol beyond the 10 week intervention.

- Trepanowski et al. [50] reported a higher dropout rate in the ADMF group (38%) vs. CER (29%), with more participants in the ADMF group reporting dissatisfaction with the diet as a reason for withdrawal.

- Harvie et al. [40] reported that fewer participants in the 2DW IMF group planned to continue the diet at the end of the study compared to the CER group (58% vs. 85%).

- We only identified eleven randomized controlled trials greater than 8 weeks in duration that have compared IMF to CER with weight loss as a primary outcome. Nine of these studies report no significant differences in weight or body fat loss between IMF and CER, and in the two studies that found significant differences, they were relatively modest. Generally, these studies have not been sufficiently powered to show equivalence in weight loss or to detect differences in body composition. The majority of studies are less than 26 weeks in duration and no studies to date have included a true follow-up period, leaving open the question of whether IMF is a durable weight loss strategy over longer periods of time
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Re: Reflecting On The 5:2 Diet & Intermittent Fasting

Postby JeffN » Mon Nov 11, 2019 7:10 am

I thought his was a pretty good overview of IF, much all of which is covered in this thread.

Intermittent Fasting Is the Diet of the Moment -
Is it better than any other diet, or is it just a novelty?

https://heated.medium.com/headlines-sho ... 0e80706cfa

"For now, the only reliable conclusion is that intermittent fasting is a viable tactic for calorie control. It should always be combined with good food choices on the non-fasting days. If tempted to try it in that context, it’s generally best to confer with a doctor first if you have any medical conditions or take medication.

Be aware, though, that claims of metabolic magic with intermittent fasting have been oversold. Expect weight loss and health improvement commensurate with your calorie restrictions, and you’ll spare yourself the fury of disappointment."



And don't forget the increased adverse effects

In Health
Jeff
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