Effects of intermittent fasting on health markers in those with type 2 diabetes: A pilot study

Advancing Chrononutrition for Cardiometabolic Health: A 2023 National Heart, Lung, and Blood Institute Workshop Report

The circadian system maintains optimal biological functions at the appropriate time of day, and the disruption of this organization can contribute to the pathogenesis of cardiometabolic disorders. The timing of eating is a prominent external time cue that influences the circadian system. "Chrononutrition" is an emerging dimension of nutrition and active area of research that examines how timing-related aspects of eating and nutrition impact circadian rhythms, biological processes, and disease pathogenesis. There is evidence to support chrononutrition as a form of chronotherapy, such that optimizing the timing of eating may serve as an actionable strategy to improve cardiometabolic health. This report summarizes key information from the National Heart, Lung, and Blood Institute's virtual workshop entitled "Chrononutrition: Elucidating the Role of Circadian Biology and Meal Timing in Cardiometabolic Health," which convened on May 2 to 3, 2023, to review current literature and identify critical knowledge gaps and research opportunities. The speakers presented evidence highlighting the impact on cardiometabolic health of earlier and shorter eating windows and more consistent day-to-day eating patterns. The multidimensionality of chrononutrition was a common theme, as it encompasses multiple facets of eating along with the timing of other behaviors including sleep and physical activity. Advancing the emerging field of chrononutrition will require: (1) standardization of terminology and metrics; (2) scalable and precise tools for real-world settings; (3) consideration of individual differences that may act as effect modifiers; and (4) deeper understanding of social, behavioral, and cultural influences. Ultimately, there is great potential for circadian-based dietary interventions to improve cardiometabolic health.

Protocol for a 1-year randomised, controlled, parallel group, open-label trial on the effects and feasibility of time-restricted eating in individuals with type 2 diabetes- The REStricted Eating Time in the treatment of type 2 diabetes (RESET2) trial

AIM

Time-restricted eating (TRE) limits the time for food intake to typically 6-10 h/day without other dietary restrictions. The aim of the RESET2 (the REStricted Eating Time in the treatment of type 2 diabetes) trial is to investigate the effects on glycaemic control (HbA1c) and the feasibility of a 1-year TRE intervention in individuals with overweight/obesity and type 2 diabetes. The aim of the present paper is to describe the protocol for the RESET2 trial.

METHODS

RESET2 is a randomised, controlled, parallel-group, open-label trial. One hundred and sixty individuals with type 2 diabetes (HbA1c >53 mmol/mol (>7.0%)), and Body Mass Index ≥25 kg/m2 will be randomised to standard care plus TRE, or to standard care and habitual living. Both the intervention and control group will follow standard diabetes care including regular clinical visits 3-4 times/year. The intervention is divided into two periods: (1) a 3-month TRE period with a fixed eating window with a self-selected timing to obtain data from the participants' experiences with TRE and (2) a 9-month individually adjusted TRE period. Participants in the TRE group will be instructed to reduce their eating window by a minimum of 3 h/day compared to the habitual eating window and with an eating window of 8-10 h/day. Test days will be scheduled at baseline, after 3 months and after 1 year. The primary outcome is HbA1c (evaluated 3 months and 1 year after randomisation) and secondary outcomes are body weight, fat mass, continuous glucose monitoring derived time-in-range and use of antidiabetic medicine (evaluated 1 year after randomisation). Additionally, we will conduct a process evaluation to assess whether the TRE intervention functioned as hypothesised.

Time-Restricted Eating is a Feasible Dietary Strategy in the Treatment of Complicated Type 2 Diabetes: The RESET2 Pilot Study

OBJECTIVE

To investigate the feasibility of a 12-week time-restricted eating (TRE) intervention targeting people with overweight/obesity and complicated type 2 diabetes to inform the design of a 1-year randomized controlled trial.

METHODS

In this single-arm pilot study, 20 participants with overweight/obesity and complicated type 2 diabetes were recruited from the diabetes clinics at Hvidovre Hospital and Steno Diabetes Center Copenhagen in the Greater Copenhagen area, Denmark. Participants followed 8 weeks of strict 10-hour TRE, followed by a 4-week TRE period with individual adjustments and support options.

RESULTS

Nineteen participants completed the intervention. Median (quartile 1-quartile 3) adherence to the eating window across all 12 weeks was 94% (86-98). Mean (95% confidence interval) reductions in body weight of -2.0 kg (-2.9 to -1.1) and hemoglobin A1c of -0.4% (-0.6 to -0.1) were observed. Participants expressed that the individualized options added flexibility to the eating concept, enabled the maintenance of social life, and eased challenging times with TRE.

CONCLUSIONS AND IMPLICATIONS

Twelve weeks of TRE was feasible. Individualized adjustments and support may have the potential to facilitate the maintenance of long-term TRE.

Effects of Time-Restricted Fasting-Nicotinamide Mononucleotide Combination on Exercise Capacity via Mitochondrial Activation and Gut Microbiota Modulation

BACKGROUND/OBJECTIVES

Athletic performance matters for athletes and fitness enthusiasts. Scientific dietary intervention may boost athletic performance alongside training. Intermittent fasting, like time-restricted fasting (TF), may enhance metabolic health. NAD+ supplement nicotinamide mononucleotide (NMN) improves mitochondrial activity. Both potentially boost athletic performance. However, whether TF combined with NMN treatment can further enhance athletic ability is unclear.

METHODS

Healthy Kunming mice were utilized to test the effects of NMN and TF on the athletic performance of mice. To simulate the in vivo state and further verify the role of TF and NMN, low glucose combined with NMN was used to intervene in C2C12 cells. The exercise capacity of mice was evaluated through motor behavior experiments. At the same time, blood gas analysis and kit tests were used to assess oxygen uptake capacity and post-exercise oxidative stress levels. Muscle development and mitochondrial function were examined through gene expression, protein analysis, and enzyme activity tests, and the distribution of intestinal microbiota and short-chain fatty acid content were also analyzed.

RESULTS

The results show that TF combined with NMN improved mitochondrial dynamics and biosynthesis, mitochondrial respiratory function, and oxidative metabolism. Then, the intervention enhanced mice's endurance, limb strength, motor coordination, and balance and reduced oxidative damage after exercise. Moreover, TF combined with NMN significantly increased the gut microbiota diversity and upregulated Ruminococcus, Roseburia, and Akkermansia in intestinal bacteria and short-chain fatty acids, which are associated with athletic performance.

CONCLUSION

TF combined with NMN enhanced mitochondrial function, improved energy metabolism, modulated the gut microbiota and short-chain fatty acids, and affected muscle fiber transformation, ultimately leading to an overall improvement in exercise performance. These findings provide a theoretical framework for expanding the application of NMN and TF in kinesiology.

[Effects of intermittent fasting and sports performance: a narrative review]

Introduction

Recently, fasted exercise has generated interest for its potential to stimulate metabolic and performance adaptations. The present study aims to analyze the effects of fasting and fasted training on performance and metabolism, acutely and chronically. The databases Medline (PubMed), Physiotherapy Evidence Database (PEDro), Cochrane, and Google Scholar were searched. In total, 767 studies were identified. Of those, 51 studies were finally included. Acutely, exercise on fasting promotes fat oxidation at low and moderate intensities, while protein catabolism is not increased. Performance is not affected in efforts lower than 1 hour. Chronically, fasting generates greater efficiency in fat metabolism and the ability to regulate blood glucose in the long term, although it has not been possible to determine whether these findings improve sports performance. More research is needed in elite athletes, with high training loads and with a periodized approach to fasting.

Intermittent Fasting and Probiotics: Synergistic Modulation of Gut Health for Therapeutic Advantages

Intermittent fasting (IF) is an increasingly popular dietary approach involving alternating fasting and eating periods. This review aims to summarize the growing body of literature demonstrating that IF is a potential nutritional practice that involves alternating periods of fasting and eating and the numerous benefits of IF, especially in the modulation of healthy gut microbiota. The positive impact of intermittent fasting on gut microbiota not only promotes gastrointestinal health but also has far-reaching effects on critical systems throughout the body. Additionally, the evidence presented in this review highlights the significant preventive and therapeutic effects of intermittent fasting on a wide range of disorders. This includes reducing the risk of diabetes, and neurological disorders, alleviating obesity, and enhancing the functioning of the liver, ultimately contributing to the maintenance of metabolic equilibrium. Perhaps most notably, these effects play a substantial role in preventing diabetes, a global health concern of increasing significance. This comprehensive investigation delves into the scientific foundations of intermittent fasting's impact on gut microbiota and its implications for averting chronic diseases, providing valuable insights for future research and therapeutic applications.

The Effect of the 14:10-Hour Time-Restricted Feeding (TRF) Regimen on Selected Markers of Glucose Homeostasis in Diet-Induced Prediabetic Male Sprague Dawley Rats

BACKGROUND

Prediabetes is a condition that often precedes the onset of type 2 diabetes mellitus (T2DM). Literature evidence indicates that prediabetes is reversible, making it an important therapeutic target for preventing the progression to T2DM. Several studies have investigated intermittent fasting as a possible method to manage or treat prediabetes.

OBJECTIVES

This study evaluated the impact of a 14:10-hour time-restricted feeding (TRF) regimen on leptin concentration, insulin sensitivity and selected markers associated with the insulin signalling pathway and glucose homeostasis in diet-induced prediabetic rats.

METHODS

Twenty-four male Sprague Dawley rats were obtained and randomly divided into two dietary groups: group 1 (n = 6) received a standard diet and water, while group 2 (n = 18) was provided a high-fat, high-carbohydrate (HFHC) diet supplemented with 15% fructose for a period of 20 weeks to induce prediabetes. After confirming prediabetes, an intermittent fasting (IF) regimen was assigned to the rats while also having untreated and metformin-treated prediabetic rats serving as controls.

RESULTS

Both IF and HFHC-Met groups yield significantly lower blood glucose, leptin and BMI results compared to the prediabetic group. The IF group yielded significantly lower insulin, HOMA-IR and HbA1C than both controls.

CONCLUSIONS

The study showed the potential of IF in alleviating prediabetes-induced dysregulation of glucose homeostasis and therefore warrants further investigations into its use in the management of prediabetes.

Assessing the impact of intermittent fasting and a low-carbohydrate-high-protein diet on metabolic health and pancreatic histopathology in type 2 diabetic rat model

Objective

The current study was conducted to investigate the effect of intermittent fasting (IF) with a low-carbohydrate-high-protein (LCHP) diet on blood glucose control in streptozotocin (STZ)-nicotinamide-induced type 2 diabetic rats (DR).

Methods

Thirty male Wistar rats were divided into six groups (n = 5) including a group of normal rats (NR) that received a control diet (CD) (50% carbohydrates, 17% protein, and 33% fat) with ad libitum (AL) feeding. The remaining 5 groups were DR injected with STZ and fed on CD or LCHP diet (40% carbohydrates, 30% protein, and 30% fat) for 6 weeks, either AL or IF (with a time-restricted feeding of 16 h followed by 8 h feeding period). There was a standard control group treated with metformin and fed on CD with AL feeding. A random blood glucose was measured. Changes in body weight and feed intake (FI) were monitored weekly.

Results

Feeding rats on LCHP and IF and their combination significantly reduced FI, body weight gain, blood glucose (P < 0.001), and improved insulin resistance (P < 0.05) with no effect on the insulin levels (P > 0.05). LCHP and IF decreased the levels of triglycerides and very-low-density lipoprotein and showed a possible protection against atherosclerosis by reducing the atherogenic index (P < 0.01). Furthermore, LCHP+IF greatly alleviates the pancreatic histopathological changes induced by STZ and showed the normal histological structure of the Langerhans islets.

Conclusion

IF with a LCHP diet could be effectively used in improving the indicators of glucose control, and reversing pancreatic histopathological alterations in type 2 diabetes.

Fasting the brain for mental health

Unfavorable socioeconomic and geopolitical conditions such as poverty, violence and inequality increase vulnerability to mental disorders. Also, exposure to a poor nutrition such as high-energy dense (HED) diets has been linked to alterations in brain function, leading to anxiety, addiction, and depression. HED diets rich in saturated fatty acids or obesity can activate the innate immune system in the brain, especially microglia, increasing proinflammatory cytokines such as interleukin 1 beta (IL1-β) and interleukin 6 (IL-6), in part, by the stimulation of toll-like receptor 4 (TLR4) and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. Intermittent fasting (IF), an eating protocol characterized by alternating periods of fasting with periods of eating, has gained recognition as a weight-management strategy to reduce obesity. Accordingly, during IF inflammation and brain function can be modulated by production of ketone bodies and modulation of the intestinal microbiota, which also promote the induction of brain-derived neurotrophic factor (BDNF), which is involved in neurogenesis and neuronal plasticity. Although IF has contributed to reduce body weight and improve metabolic profiles, its influence on mental health remains an evolving field of research. Here, we provide experimental evidence supporting the role of IF reducing neuroinflammation as a valuable approach to improve mental health.

Economic Evaluation of Fasting Mimicking Diet Versus Standard Care in Diabetic Patients on Dual or Triple Medications at Baseline in the United States: A Cost-Utility Analysis

OBJECTIVES

According to most guidelines, dietary interventions are essential in the management of diabetes. Fasting has emerged as potential therapeutic regimes for diabetes. The proof-of-concept study and the fasting in diabetes treatment trial are the first to explore the clinical impact of the Fasting Mimicking Diet (FMD) in patients with type 2 diabetes mellitus. Their results showed that FMD cycles improve glycemic management and can be integrated into usual care complementary to current guidelines. This economic evaluation aims to assess the 10-year quality-of-life effects, cost implications, and cost-effectiveness of adding a 3-year FMD program to diabetes standard care in diabetic population on dual or triple medications at baseline from the perspective of the US payer.

METHODS

We constructed a microsimulation model in TreeAge using a published US-specific diabetes model. The model was populated using FMD effectiveness outcomes and publicly available clinical and economic data associated with diabetes complications, use of diabetes medications, hypoglycemia incidence, direct medical costs in 2021 USD, quality of life, and mortality. All benefits were discounted by 3%.

RESULTS

This cost-utility analysis showed that the FMD program was associated with 11.4% less diabetes complications, 67.2% less overall diabetes medication use, and 45.0% less hypoglycemia events over the 10-year simulation period. The program generated an additional effectiveness benefit of 0.211 quality-adjusted life year and net monetary benefit of 41 613 USD per simulated patient. Thus, the FMD program is cost saving.

CONCLUSIONS

These results indicate that the FMD program is a beneficial first-line strategy in T2DM management.

Comparing the effects of time-restricted eating on glycaemic control in people with type 2 diabetes with standard dietetic practice: A randomised controlled trial

AIMS

To test the efficacy of time-restricted eating (TRE) in comparison to dietitian-led individualised dietary guidance to improve HbA1c in people with Type 2 diabetes mellitus.

METHODS

In a parallel groups design, 51 adults (35-65 y) with Type 2 diabetes mellitus and overweight/obesity (HbA1c ≥6.5% (48 mmol/mol), BMI ≥25-≤40 kg/m2) commenced a six-month intervention. Following baseline, participants were randomised to TRE (1000-1900 h) or DIET (individualised dietetic guidance) with four consultations over four months. Changes in HbA1c (primary), body composition, and self-reported adherence (secondary) were analysed using linear mixed models. A non-inferiority margin of 0.3% (4 mmol/mol) HbA1c was set a priori.

RESULTS

Forty-three participants (56 ± 8 y, BMI: 33 ± 5 kg/m2, HbA1c: 7.6 ± 0.8%) completed the intervention. HbA1c was reduced (P=0.002; TRE: -0.4% (-5 mmol/mol), DIET: -0.3% (-4 mmol/mol)) with no group or interaction effects; TRE was non-inferior to DIET (-0.11%, 95%CI: -0.50% to 0.28%). Body mass reduced in both groups (TRE: -1.7 kg; DIET: -1.2 kg) via ∼900 kJ/d spontaneous energy reduction (P<0.001). Self-reported adherence was higher in TRE versus DIET (P<0.001).

CONCLUSIONS

When individualised dietary guidance is not available, effective, and/or suitable, TRE may be an alternative dietary strategy to improve glycaemic control in people with Type 2 diabetes mellitus.

Intermittent fasting and cardiovascular disease: A scoping review of the evidence

Intermittent fasting (IF), characterized by alternating periods of fasting and unrestricted eating, typically within an 8-hour window or less each day, has gained significant attention as a possible dietary approach. While it is recognized for its metabolic advantages, like weight loss and enhanced glucose and insulin sensitivity, its effect on cardiovascular health remains a topic of mixed opinions. Recent findings suggest a potential downside, with reports indicating a concerning association: a 91 % higher risk of cardiovascular disease (CVD) mortality compared to eating spread across a 12- to 16-hour period. Despite this alarming statistic, the evidence cannot establish a causal link. The impact of IF on CVD is still insufficiently understood, with benefits sometimes exaggerated and risks downplayed in popular discourse. This scoping review aims to consolidate the current evidence, addressing unresolved questions about the benefits and risks of IF, particularly its association with CVD risks and mortality. The goal is to provide a balanced perspective on the potential health implications of IF, emphasizing the need for further research to clarify its long-term effects on cardiovascular health.

Effects of Fasting on Metabolic Hormones and Functions: A Narrative Review

The occurrence of the metabolic syndrome and its related diseases such as diabetes are steadily rising in our modern society. Modern food choices and the more sedentary lifestyles largely contribute to this shift in our society's health. Fasting has been practiced for religious purposes all over the world long time before science showed the benefits of it. The effects of fasting on glucose and fat metabolism are of great interest. Fasting triggers a cascade of changes in the hormonal, microbiome and enzymatic environments, leading to shifted glucose and fat metabolisms. Fasting-induced metabolic function changes are affected by several factors such as sex hormones, lipid-released hormones, growth hormone, insulin, and the gut microbiome, leading to lipolysis and the release of FFA into the bloodstream. The purpose of this review is to summarize the newest research results on the specific pathways fasting triggers to improve metabolic functions and understand the potential applications of fasting as prevention/treatment of several metabolic conditions.

It's About Timing: Contrasting the Metabolic Effects of Early vs. Late Time-Restricted Eating in Humans

PURPOSE OF REVIEW

Time-restricted eating (TRE), a form of intermittent fasting, restricts feeding time across the day, imposing a daily 'eating window'. The time of day when the eating window occurs could result in differential metabolic effects. Here, we describe recent intervention studies in humans assessing the metabolic consequences of an early- (i.e., eating window starting in the early morning) vs. late (i.e., eating window starting after midday)-TRE protocol.

RECENT FINDINGS

Well-controlled studies indicate that both TRE protocols effectively reduce body weight and improve altered glucose metabolism, lipid profile, inflammation, or blood pressure levels. An early-TRE (e-TRE) might have a further positive impact on improving blood glucose, insulin levels, and insulin resistance. However, the studies directly assessing the metabolic consequences of an early- vs. late-TRE have shown dissimilar findings, and more well-controlled clinical trials are needed on the metabolic benefits of these two types of TRE. Evidence suggests that an e-TRE might have enhanced metabolic results, particularly regarding glucose homeostasis. More long-term studies, including larger sample sizes, are needed to assess the metabolic, circadian, and adherence benefits, together with socio-cultural acceptance of both TRE approaches.

Self-initiated lifestyle changes during a fasting-mimicking diet programme in patients with type 2 diabetes: a mixed-methods study

BACKGROUND

Lifestyle changes, especially regarding diet quality and physical activity, are important in the management of type 2 diabetes (T2D). This mixed-methods study explores self-initiated lifestyle changes in patients with T2D who followed a periodic fasting-mimicking diet (FMD).

METHODS

Quantitative data were obtained from the Fasting In diabetes Treatment trial (November 2018 to August 2021) in which 100 participants with T2D, using metformin only or no medication, were randomised to receive a monthly 5-day FMD for twelve months next to usual care, or usual care only. Diet quality and physical activity questionnaires were completed at baseline, six and twelve months. Changes over time were analysed using linear mixed models. Focus groups were organized with FMD participants to explore experiences regarding self-initiated lifestyle changes. The qualitative data was analysed using the Theoretical Domains Framework.

RESULTS

Questionnaires were available from 49 FMD participants and 43 controls. No differences in diet quality were found. Total physical activity in the FMD participants changed from 34.6 to 38.5 h per week (h/wk) from baseline to twelve months, while in controls it changed from 34.9 to 29.0 h/wk (between group difference, p = 0.03). In six focus groups with FMD participants (n = 20), individual participants perceived the FMD as an encouragement for (minor) lifestyle changes. There were no barriers to behaviour change related to the FMD. Important facilitators of healthy behaviour were an increase in awareness of the impact of lifestyle on health (knowledge), better physical fitness (physical) and health improvement (reinforcement). Facilitators unrelated to the FMD included family support (social influences) and opportunities in the neighbourhood (environmental context and resources), while barriers unrelated to the FMD were experiencing health problems (physical) and social events (social influences).

CONCLUSIONS

Using an FMD for five consecutive days per month did not affect diet quality in between FMD periods in quantitative analysis, but increased the number of hours per week spent on physical activity. Qualitative analysis revealed self-initiated improvements in both diet quality and physical activity in individual participants using an FMD. Healthcare professionals could use an FMD programme as a 'teachable moment' to stimulate additional lifestyle changes.

TRIAL REGISTRATION

ClinicalTrials.gov; NCT03811587. Registered 22 January 2019.

The effect of intermittent fasting on microbiota as a therapeutic approach in obesity

Obesity, a public health challenge, arises from a complex interplay of factors such as dietary habits and genetic predisposition. Alterations in gut microbiota, characterized by an imbalance between Firmicutes and Bacteroidetes, further exacerbate metabolic dysregulation, promoting inflammation and metabolic disturbances. Intermittent fasting (IF) emerges as a promising dietary strategy showing efficacy in weight management and favoring fat utilization. Studies have used mice as animal models to demonstrate the impact of IF on gut microbiota composition, highlighting enhanced metabolism and reduced inflammation. In humans, preliminary evidence suggests that IF promotes a healthy microbiota profile, with increased richness and abundance of beneficial bacterial strains like Lactobacillus and Akkermansia. However, further clinical trials are necessary to validate these findings and elucidate the long-term effects of IF on microbiota and obesity. Future research should focus on specific tissues and cells, the use of advanced -omics techniques, and exploring the interaction of IF with other dietary patterns, to analyze microbiota composition, gene expression, and potential synergistic effects for enhanced metabolic health. While preliminary evidence supports the potential benefits of IF in obesity management and microbiota regulation, further research with diverse populations and robust methodologies is necessary to understand its implications and optimize personalized dietary interventions. This review explores the potential impact of IF on gut microbiota and its intricate relationship with obesity. Specifically, we will focus on elucidating the underlying mechanisms through which IF affects microbiota composition, as well as its subsequent effects on obesity.

Intermittent fasting and longevity: From animal models to implication for humans

In recent years, intermittent fasting (IF) and its numerous modifications have been increasingly suggested as a promising therapy for age-related problems and a non-pharmacological strategy to extend lifespan. Despite the great variability in feeding schedules that we describe in the current work, underlying physiological processes are the same and include a periodic switch from glucose metabolism (generated by glycogenolysis) to fatty acids and fatty acid-derived ketones. Many of the beneficial effects of IF appear to be mediated by optimization of energy utilization. Findings to date from both human and animal experiments indicate that fasting improves physiological function, enhances performance, and slows aging and disease processes. In this review, we discuss some of the remarkable discoveries about the beneficial effects of IF on metabolism, endocrine and cardiovascular systems, cancer prevention, brain health, neurodegeneration and aging. Experimental studies on rodent models and human investigations are summarized to compare the outcomes and underlying mechanisms of IF. Metabolic and cellular responses triggered by IF could help to achieve the aim of preventing disease, and maximizing healthspan and longevity with minimal side effects.

The effects of early time restricted eating plus daily caloric restriction compared to daily caloric restriction alone on continuous glucose levels

Background

The median eating duration in the U.S. is 14.75 h, spread throughout the period of wakefulness and ending before sleep. Food intake at an inappropriate circadian time may lead to adverse metabolic outcomes. Emerging literature suggests that time restricted eating (TRE) may improve glucose tolerance and insulin sensitivity. The aim was to compare 24-h glucose profiles and insulin sensitivity in participants after completing 12 weeks of a behavioral weight loss intervention based on early TRE plus daily caloric restriction (E-TRE+DCR) or DCR alone.

Methods

Eighty-one adults with overweight or obesity (age 18-50 years, BMI 25-45 kg/m2) were randomized to either E-TRE+DCR or DCR alone. Each participant wore a continuous glucose monitor (CGM) for 7 days and insulin sensitivity was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR) at Baseline and Week 12. Changes in CGM-derived measures and HOMA-IR from Baseline to Week 12 were assessed within and between groups using random intercept mixed models.

Results

Forty-four participants had valid CGM data at both time points, while 38 had valid glucose, insulin, HOMA-IR, and hemoglobin A1c (A1c) data at both timepoints. There were no significant differences in sex, age, BMI, or the percentage of participants with prediabetes between the groups (28% female, age 39.2 ± 6.9 years, BMI 33.8 ± 5.7 kg/m2, 16% with prediabetes). After adjusting for weight, there were no between-group differences in changes in overall average sensor glucose, standard deviation of glucose levels, the coefficient of variation of glucose levels, daytime or nighttime average sensor glucose, fasting glucose, insulin, HOMA-IR, or A1c. However, mean amplitude of glycemic excursions changed differently over time between the two groups, with a greater reduction found in the DCR as compared to E-TRE+DCR (p = 0.03).

Conclusion

There were no major differences between E-TRE+DCR and DCR groups in continuous glucose profiles or insulin sensitivity 12 weeks after the intervention. Because the study sample included participants with normal baseline mean glucose profiles and insulin sensitivity, the ability to detect changes in these outcomes may have been limited.

Unlocking the Benefits of Fasting: A Review of its Impact on Various Biological Systems and Human Health

Fasting has gained significant attention in recent years for its potential health benefits in various body systems. This review aims to comprehensively examine the effects of fasting on human health, specifically focusing on its impact on different body's physiological systems. The cardiovascular system plays a vital role in maintaining overall health, and fasting has shown promising effects in improving cardiovascular health markers such as blood pressure, cholesterol levels, and triglyceride levels. Additionally, fasting has been suggested to enhance insulin sensitivity, promote weight loss, and improve metabolic health, thus offering potential benefits to individuals with diabetes and metabolic disorders. Furthermore, fasting can boost immune function, reduce inflammation, enhance autophagy, and support the body's defense against infections, cancer, and autoimmune diseases. Fasting has also demonstrated a positive effect on the brain and nervous system. It has been associated with neuroprotective properties, improving cognitive function, and reducing the risk of neurodegenerative diseases, besides the ability of increasing the lifespan. Hence, understanding the potential advantages of fasting can provide valuable insights for individuals and healthcare professionals alike in promoting health and wellbeing. The data presented here may have significant implications for the development of therapeutic approaches and interventions using fasting as a potential preventive and therapeutic strategy.

Intermittent fasting reduces mouse body fat while maintaining muscle mass by regulating protein synthesis and autophagy

OBJECTIVES

The aim of this study is to investigate the effect of intermittent fasting (IF) on the regulation of skeletal muscle protein metabolism in response to nutrient supplementation during fasting.

METHODS

Twelve-week-old male C57BL/6J mice were assigned to two groups: ad libitum and IF, with the latter having access to food for only 3 h/d. After 6 wk of experimental periods, an oral glucose tolerance test was performed. One week later, phosphate-buffered saline or a glucose and branched-chain amino acid mixture was administered orally, and blood and tissues were collected 30 min later.

RESULTS

The oral glucose tolerance test results revealed that the IF group had better insulin sensitivity. They also had lower body and fat weights while maintaining the same level of skeletal muscle mass as the ad libitum group. The phosphorylation of ribosomal protein S6 in the skeletal muscle, a marker for the activation of protein translation, was greater in the IF group after glucose and branched-chain amino acid mixture administration. Microtubule-associated protein light chain 3-II-to-light chain 3-I ratio, a marker for autophagosome formation, in skeletal muscle during fasting was significantly lower in the IF group than that in the ad libitum group.

CONCLUSIONS

Our findings suggest that adaptation to IF regulates protein synthesis and breakdown, leading to the maintenance of skeletal muscle mass while reducing body fat.

Type 2 Diabetes Mellitus and Sarcopenia as Comorbid Chronic Diseases in Older Adults: Established and Emerging Treatments and Therapies

Type 2 diabetes mellitus (T2DM) and sarcopenia (low skeletal muscle mass and function) share a bidirectional relationship. The prevalence of these diseases increases with age and they share common risk factors. Skeletal muscle fat infiltration, commonly referred to as myosteatosis, may be a major contributor to both T2DM and sarcopenia in older adults via independent effects on insulin resistance and muscle health. Many strategies to manage T2DM result in energy restriction and subsequent weight loss, and this can lead to significant declines in muscle mass in the absence of resistance exercise, which is also a first-line treatment for sarcopenia. In this review, we highlight recent evidence on established treatments and emerging therapies targeting weight loss and muscle mass and function improvements in older adults with, or at risk of, T2DM and/or sarcopenia. This includes dietary, physical activity and exercise interventions, new generation incretin-based agonists and myostatin-based antagonists, and endoscopic bariatric therapies. We also highlight how digital health technologies and health literacy interventions can increase uptake of, and adherence to, established and emerging treatments and therapies in older adults with T2DM and/or sarcopenia.

An alternative approach to obesity treatment: intermittent fasting

Overweight and obesity are an important public health problem that affects a significant part of the world population and increases the risk of many metabolic diseases. Weight loss is the primary goal in obesity treatment, and many different dietary interventions are tried for this purpose. Intermittent fasting is a diet that has become popular in recent years with the weight loss it provides and includes periods of fasting and feeding. In addition to providing weight loss, intermittent fasting also has positive effects on important risk factors such as glucoregulatory parameters, blood lipids, and oxidative stress. Intermittent fasting appears to be an effective and safe way to achieve weight loss in obesity. It could also have therapeutic effects on obesity-related diseases. The aim of this review was to bring together up-to-date information on the effects of intermittent fasting on obesity and various obesity-related diseases, mechanisms of action, possible benefits and harms, and potential uses.

The Alteration of the Gut Microbiome during Ramadan Offers a Novel Perspective on Ramadan Fasting: A Pilot Study

An intermittent fasting regimen is widely perceived to lead to various beneficial health effects, including weight loss, the alleviation of insulin resistance, and the restructuring of a healthy gut microbiome. Because it shares certain commonalities with this dietary intervention, Ramadan fasting is sometimes misinterpreted as intermittent fasting, even though there are clear distinctions between these two regimens. The main purpose of this study is to verify whether Ramadan fasting drives the same beneficial effects as intermittent fasting by monitoring alterations in the gut microbiota. We conducted a study involving 20 Muslim individuals who were practicing Ramadan rituals and assessed the composition of their gut microbiomes during the 4-week period of Ramadan and the subsequent 8-week period post-Ramadan. Fecal microbiome analysis was conducted, and short-chain fatty acids (SCFAs) were assessed using liquid-chromatography-mass spectrometry. The observed decrease in the levels of SCFAs and beneficial bacteria during Ramadan, along with the increased microbial diversity post-Ramadan, suggests that the daily diet during Ramadan may not provide adequate nutrients to maintain robust gut microbiota. Additionally, the notable disparities in the functional genes detected through the metagenomic analysis and the strong correlation between Lactobacillus and SCFAs provide further support for our hypothesis.

Time-Restricted Feeding and Intermittent Fasting as Preventive Therapeutics: A Systematic Review of the Literature

Multiple studies have shown that intermittent fasting (IF) is associated with better health conditions and longer lifespans, as is time-restricted feeding (TRF). One crucial explanation is that IF and TRF permit a set length of time for caloric ingestion, during which our systems activate a variety of mechanisms that lead to the enhancement and renewal of different body systems. Accordingly, the benefits of IF and TRF are a lot greater than those of complete calorie restriction (CR). Accordingly, TRF and IF offered the underpinnings for human studies that revealed that when we eat and when we are fasting, we experience fluctuations in all body systems. For relevant medical literature, we investigated medical databases such as PubMed/Medline, PubMed Central, Cochrane Library, and Google Scholar. The chosen articles were evaluated based on eligibility criteria and vetted by quality evaluation methods; 15 finished research papers were included in the study. Of the 15 recognized studies, four were systematic reviews of literature, and 11 were review articles. The chosen publications all examined the efficacy and comparability with other restrictive diets. The study articles indicated that the advantages of IF and TRF represent complex interplay involving periodic digestion of food, gut flora, and the circadian clock. Accordingly, further research is necessary to get a comprehensive grasp of this very complex molecular blueprint. This could aid in producing an effectively planned food treatment that can regulate numerous chronic health ailments and disorders. Furthermore, it might lead to the development and investigation of new pharmacological medicines that mimic the nutritional and therapeutic benefits of IF for those who are unwilling or unable to follow this kind of feeding regimen.

Eating window and eating habits of adults in China: A cross-sectional study

Objective

Previous studies have demonstrated that eating time and habits play key roles in human health. However, there is a paucity of research on the epidemiology of eating window and eating habits in China. This study aimed to investigate the relationship between eating window and eating habits among adults in mainland China and explore the factors influencing these parameters.

Design

Cross-sectional study.

Setting

A questionnaire comprising demographic data, metabolic index, eating window and eating habits was administered via the Internet.

Participants

1596 adults from mainland China.

Results

Eating window of all participants was 13.03 ± 2.02 h (mean ± standard deviation [SD]), which was longer than previously reported in smaller more controlled studies from China. Area of residence and occupation were significant factors influencing eating window after controlling for other factors (area of residence: β, -0.499; 95% confidence interval [CI], -0.897 to -0.101, p = 0.014; occupation: β, -0.309, 95% CI, -0.496 to -0.121, p = 0.001). Participants typically commenced eating at 08:00 h (interquartile range [IQR]: 8:00-9:00) and ceased eating at 20:00 h (IQR: 20:00-22:00). Regular meals which mean two or three meals per day regularly constituted the dominant eating pattern of participants (n = 1233, 77.3%) and 819 (51.1%) participants preferred cooking for themselves.

Conclusion

This study revealed that eating window of adults in China generally around 13 h. Area of residence and occupation were the main factors influencing eating window. Our data provide a foundation for future studies on eating window and eating habits in China.

Feasibility of time-restricted eating in individuals with overweight, obesity, prediabetes, or type 2 diabetes: A systematic scoping review

OBJECTIVE

This systematic scoping review aimed to map and synthesize research on feasibility of time-restricted eating (TRE) in individuals with overweight, obesity, prediabetes, or type 2 diabetes, including recruitment rate, retention rate, safety, adherence, and participants' attitudes, experiences, and perspectives.

METHODS

The authors searched MEDLINE, Embase, and Cumulative Index to Nursing and Allied Health Literature from inception to November 22, 2022, supplemented by backward and forward citation search.

RESULTS

From 4219 identified records, 28 studies were included. In general, recruitment was easy and median retention rate was 95% among studies with <12 weeks duration and 89% among studies ≥12 weeks. Median (range) adherence to the target eating window for studies <12 and ≥12 weeks was 89% (75%-98%) and 81% (47%-93%), respectively. Variation in adherence among participants and studies was considerable, indicating that following TRE was difficult for some people and that intervention conditions influenced adherence. These findings were supported by qualitative data synthetized from seven studies, and determinants of adherence included calorie-free beverages outside the eating window, provision of support, and influence on the eating window. No serious adverse events were reported.

CONCLUSIONS

TRE is implementable, acceptable, and safe in populations with overweight, obesity, prediabetes, or type 2 diabetes, but it should be accompanied by support and options for individual adjustments.

Effects of Intermittent Fasting on Regulation of Metabolic Homeostasis: A Systematic Review and Meta-Analysis in Health and Metabolic-Related Disorders

Intermittent fasting (IF) is an emerging dietetic intervention that has been associated with improved metabolic parameters. Nowadays, the most common IF protocols are Alternate-Day Fasting (ADF) and Time-Restricted Fasting (TRF), but in this review and meta-analysis we have also considered Religious Fasting (RF), which is similar to TRF but against the circadian rhythm. The available studies usually include the analysis of a single specific IF protocol on different metabolic outcomes. Herein, we decided to go further and to conduct a systematic review and meta-analysis on the advantages of different IF protocols for metabolic homeostasis in individuals with different metabolic status, such as with obesity, diabetes mellitus type 2 (T2D) and metabolic syndrome (MetS). Systematic searches (PubMed, Scopus, Trip Database, Web of Knowledge and Embase, published before June 2022) of original articles in peer-review scientific journals focusing on IF and body composition outcomes were performed. Sixty-four reports met the eligibility criteria for the qualitative analysis and forty-seven for the quantitative analysis. Herein, we showed that ADF protocols promoted the major beneficial effects in the improvement of dysregulated metabolic conditions in comparison with TRF and RF protocols. Furthermore, obese and MetS individuals are the most benefited with the introduction of these interventions, through the improvement of adiposity, lipid homeostasis and blood pressure. For T2D individuals, IF impact was more limited, but associated with their major metabolic dysfunctions-insulin homeostasis. Importantly, through the integrated analysis of distinct metabolic-related diseases, we showed that IF seems to differently impact metabolic homeostasis depending on an individual's basal health status and type of metabolic disease.

Designing a Co-created Intervention to Promote Motivation and Maintenance of Time-Restricted Eating in Individuals With Overweight and Type 2 Diabetes

OBJECTIVE

To design an appealing time-restricted eating (TRE) intervention by exploring behavioral and social mechanisms to improve TRE adoption and maintenance among people with type 2 diabetes (T2D) and overweight. Time-restricted eating is an intermittent fasting regimen suggested to improve glycemic control and body weight.

METHODS

Intervention development combined coherence theory and empirical data (workshops and semistructured interviews with the target group, their relatives, and health care professionals [HCPs]). Abductive analysis was applied.

RESULTS

The analysis suggested designing the TRE intervention in 2 phases: a short period with strict TRE, followed by a longer period focusing on adapting TRE to individual needs with support from HCPs, relatives, and peers. To reinforce TRE motivation and maintenance, HCPs should adopt a whole-person approach that focuses on participants' previous experiences.

CONCLUSIONS AND IMPLICATIONS

Important intervention elements to promote TRE adoption and maintenance are suggested to include a 2-phase design and support from professionals, family, and peers.

The Health-Promoting Effects and the Mechanism of Intermittent Fasting

Intermittent fasting (IF) is an eating pattern in which individuals go extended periods with little or no energy intake after consuming regular food in intervening periods. IF has several health-promoting effects. It can effectively reduce weight, fasting insulin levels, and blood glucose levels. It can also increase the antitumor activity of medicines and cause improvement in the case of neurological diseases, such as memory deficit, to achieve enhanced metabolic function and prolonged longevity. Additionally, IF activates several biological pathways to induce autophagy, encourages cell renewal, prevents cancer cells from multiplying and spreading, and delays senescence. However, IF has specific adverse effects and limitations when it comes to people of a particular age and gender. Hence, a more systematic study on the health-promoting effects and safety of IF is needed. This article reviewed the research on the health-promoting effects of IF, providing a theoretical basis, direction for subsequent basic research, and information related to the clinical application of IF.

Metabolic effects of alternate-day fasting in males with obesity with or without type 2 diabetes

Alternate-day fasting induces oscillations in energy stores. We hypothesized that repeated oscillations increases insulin secretion and sensitivity, and improve metabolic health in patients with obesity with or without type 2 diabetes (T2DM). Twenty-three male patients fasted every other day for 30 h for 6 weeks. Experiments included resting energy expenditure, continuous glucose monitoring, intravenous glucose tolerance test, euglycemic hyperinsulinemic clamp, body composition, hepatic triglyceride content, muscle biopsies which were performed at baseline, during 3 weeks without allowed weight loss, and after additional 3 weeks with weight loss. Bodyweight decreased ∼1% and further ∼3% during weeks one to three and four to six, respectively (p < 0.05). Only minor changes in fat mass occurred in weeks 1-3. With weight loss, visceral fat content decreased by 13 ± 3% and 12 ± 2% from baseline in patients with and without T2DM, respectively (p < 0.05). Hepatic triglyceride content decreased by 17 ± 9% and 36 ± 9% (with diabetes) and 27 ± 8% and 40 ± 8% (without diabetes) from baseline to week 3 and week 6, respectively (all p < 0.05). Muscle lipid and glycogen content oscillated with the intervention. Glucose homeostasis, insulin secretion and sensitivity was impaired in patients with T2DM and did not change without weight loss, but improved (p < 0.05) when alternate day fasting was combined with weight loss. In conclusion, alternate-day fasting is feasible in patients with obesity and T2DM, and decreases visceral fat and liver fat deposits. Energy store oscillations by alternate-day fasting do not improve insulin secretion or sensitivity per se. Clinical Trial registration: (ClinicalTrials.gov), (ID NCT02420054).

Use of Patient-Reported Outcomes for Assessing Diabetes Outcomes

The treatment of diabetes can be complex and overwhelming for patients as it demands persistent attention to lifestyle management, adherence to medications, monitoring of side effects of drugs, and management of devices for glucose monitoring and/or insulin infusion. Therefore, understanding patient-reported outcomes (PROs) that provide direct insight into the patient's experience with diabetes is crucial for optimizing diabetes management.This review provides an overview of commonly used PRO questionnaires that assess different aspects of diabetes management.

Effects of Time-Restricted Feeding and Ramadan Fasting on Body Weight, Body Composition, Glucose Responses, and Insulin Resistance: A Systematic Review of Randomized Controlled Trials

Time-restricted feeding (TRF) and Ramadan fasting (RF) have been recently associated with several health outcomes. However, it is not yet clear if they are superior to existing treatments in terms of glucose metabolism, insulin action, and weight loss. This review aims to summarize the current data on the effects of these regimes on body weight, body composition, and glycemia. An electronic search was conducted in PUBMED and SCOPUS databases up to August 2022. Twenty-four records met the inclusion criteria and underwent a risk-of-bias assessment. The main outcomes were: (a) TRF may result in moderate weight loss in individuals with overweight/obesity; when TRF is combined with caloric restriction, weight loss is >5% of the initial body weight, (b) 14 h of fasting may be as effective as 16 h in terms of weight loss, and (c) TRF may lead to improved insulin sensitivity and glycemic responses/variability throughout the day in individuals with overweight/obesity. Concerning RF, only two studies were available and thus, conclusions were not drawn. TRF may be an effective nutritional approach for weight loss, and the amelioration of glycemic control and insulin sensitivity in individuals with overweight/obesity. However, more long-term, well-designed studies are needed.

Beneficial effect of time-restricted eating on blood pressure: a systematic meta-analysis and meta-regression analysis

Background

As a cardiometabolic disease, hypertension has shown an obvious upward trend, becoming a global epidemic chronic disease. Lifestyle intervention is a fundamental method for lowering blood pressure. This systematic review and meta-analysis aimed to evaluate the effects of time-restricted eating (TRE) on blood pressure.

Methods

Studies were retrieved from the PubMed, Embase, Cochrane Library, and Web of Science databases to evaluate the effects of TRE on blood pressure. The time frame of search was from the start of database construction until July 14, 2022.There were no language restrictions. Meta-analysis and meta-regression were performed using Stata version 16. The weighted mean difference with 95% CI was used to assess the effect of TRE on blood pressure, heart rate, weight, blood glucose, total cholesterol, HDL-C, LDL-C, and triglycerides. The main ending of this article were blood pressure and heart rate, while the secondary ending were weight, blood glucose, total cholesterol, HDL-C, LDL-C, and triglycerides.

Results

Ten randomized controlled trials involving 694 patients were identified. TRE significantly reduced systolic blood pressure (SBP) (mean difference = −4.15; 95% CI: −6.73, −2.30; P < 0.0001), but had no significant effect on diastolic blood pressure (DBP) (mean difference = −2.06; 95% CI: −4.16, 0.02; P = 0.053) and no beneficial effect on heart rate (mean difference = 0.36; 95% CI: −2.83, 3.54; P = 0.0825). TRE promoted weight loss (mean difference = −1.63; 95% CI: −2.61, −0.64; P = 0.001) and decreased blood glucose levels (mean difference = −2.80; 95% CI: −4.64, −0.96; P = 0.003), but had no significant effect on total cholesterol (mean difference = 0.03, 95% CI: −10.01, 10.08; P = 0.995), HDL-C (mean difference = 0.85, 95% CI: −1.80, 3.49; P = 0.531), LDL-C (mean difference = −0.86, 95% CI: −6.47, 4.76; P = 0.764), or triglycerides (mean difference = −3.524, 95% CI: −9.49, 2.45; P = 0.248). In a separate meta-regression analysis, the degree of SBP change was related to weight loss (P = 0.044) but not to glucose improvement (P = 0.867).

Conclusions

The present meta-analysis suggests that TRE significantly reduced SBP, while no effect of reducing DBP was seen. The observed lower blood pressure may be attributed to significant weight loss. The effects of TRE on heart rate and blood lipid levels were not apparent.

Time-restricted eating for patients with diabetes and prediabetes: A systematic review

Background

Several studies have explored the effect of time-restricted eating (TRE) on patients with diabetes and prediabetes. However, these studies have not been analyzed and summarized as a whole. We conducted a systematic review to summarize and analyze all studies about the efficacy and safety of TRE for patients with diabetes and prediabetes.

Methods

We conducted a comprehensive search of the Embase, PubMed and Cochrane databases and the time span was from inception to 1 May 2022. The Cochrane Collaboration's Risk of Bias 2 (RoB2) and ROBINS-I tools were used to evaluate the quality of included studies. The effect of TRE on weight loss, insulin sensitivity, plasma glucose, and the safety of TRE were summarized and analyzed.

Results

In total, 7 studies with 326 participants including 5 articles with 217 patients with diabetes and 2 articles with 109 patients with prediabetes were included. The TRE windows were from 4 to 10 h. The percentages of females ranged from 0 to 90%. The mean age ranged from 35.2 to 67.5 years, and most of patients adhered to TRE. All studies were assessed as high quality. TRE may result in weight loss, and improvements in the insulin sensitivity and plasma glucose, with no severe AEs.

Conclusion

Time-restricted eating is a safe and feasible intervention, and may offer cardiovascular and metabolic benefits for patients with diabetes and prediabetes. Studies in this field, which should be viewed as important, are limited. Therefore, more high-quality studies are needed.

A Narrative Review on Intermittent Fasting as an Approachable Measure for Weight Reduction and Obesity Management

Obesity can be regarded as the curse of this modern advanced and efficient lifestyle as it is the crux of very precarious comorbidities. The prevalence of obesity is so widespread that cases of obesity can be seen on either end of the age spectrum. With the rise of the twenty-first century and the rise of ease of living, the sedentary lifestyle also went on the rise to become the primary contributor to the rise in obesity. For the management of obesity, various dietary modifications grew in popularity, among which is intermittent fasting. Intermittent fasting grew in popularity with the rise of the internet. Intermittent calorie restriction/time-restricted feeding is a form of caloric restriction revolving around a short window for eating and a comparatively larger window for fasting. This form of feed-fast cycle promotes increased consumption of adipose tissue and glycogen stores, leading to increased fat loss and reduced satiety. Intermittent fasting is also said to have cardioprotective functions as well known to control diabetic parameters and reduce the incidence of diabetes. This narrative review article's goals are to outline the benefits of intermittent calorie restriction while accounting for any of its potential limitations and pinpoint any knowledge gaps that may exist.

Fatty acids homeostasis during fasting predicts protection from chemotherapy toxicity

Fasting exerts beneficial effects in mice and humans, including protection from chemotherapy toxicity. To explore the involved mechanisms, we collect blood from humans and mice before and after 36 or 24 hours of fasting, respectively, and measure lipid composition of erythrocyte membranes, circulating micro RNAs (miRNAs), and RNA expression at peripheral blood mononuclear cells (PBMCs). Fasting coordinately affects the proportion of polyunsaturated versus saturated and monounsaturated fatty acids at the erythrocyte membrane; and reduces the expression of insulin signaling-related genes in PBMCs. When fasted for 24 hours before and 24 hours after administration of oxaliplatin or doxorubicin, mice show a strong protection from toxicity in several tissues. Erythrocyte membrane lipids and PBMC gene expression define two separate groups of individuals that accurately predict a differential protection from chemotherapy toxicity, with important clinical implications. Our results reveal a mechanism of fasting associated with lipid homeostasis, and provide biomarkers of fasting to predict fasting-mediated protection from chemotherapy toxicity.

Fasting has been reported to protect from chemotherapy-associated toxicity. Here, the authors show that fatty acid profiles in erythrocyte membranes and gene expression from peripheral blood mononuclear cells are associated to the fasting-mediated benefits during cancer treatment in mice and patients.

Randomized controlled trial for time-restricted eating in overweight and obese young adults

Time-restricted eating (TRE) is known to improve metabolic health, whereas very few studies have compared the effects of early and late TRE (eTRE and lTRE) on metabolic health. Overweight and obese young adults were randomized to 6-h eTRE (eating from 7 a.m. to 1 p.m.) (n = 21), 6-h lTRE (eating from 12 p.m. to 6 p.m.) (n = 20), or a control group (ad libitum intake in a day) (n = 19). After 8 weeks, 6-h eTRE and lTRE produced comparable body weight loss compared with controls. Compared with control, 6-h eTRE reduced systolic blood pressure, mean glucose, fasting insulin, insulin resistance, leptin, and thyroid axis activity, whereas lTRE only reduced leptin. These findings shed light on the promise of 6-h eTRE and lTRE for weight loss. Larger studies are needed to assess the promise of eTRE to yield better thyroid axis modulation and overall cardiometabolic health improvement.

Role of Intermittent Fasting in the Management of Prediabetes and Type 2 Diabetes Mellitus

Diabetes mellitus (DM) is a highly prevalent disease in the modern society. It can be defined as a group of metabolic diseases marked by chronic hyperglycemia arising from defects in insulin secretion or resistance to insulin action, or both. Its predecessor, prediabetes, is also an important entity, and its management is essential to prevent its progression to DM. Together, these entities burden global health and the world economy, and therefore, prevention and management are key to improving global health and reducing the financial burden on the world economy. Comprehensive lifestyle modification has been proven to be a safe and effective method for preventing the progression of prediabetes and treatment of type 2 diabetes mellitus. Lifestyle modifications such as weight loss, exercise, and diets such as low-carbohydrate one, Mediterranean, and very low calorie diets are traditionally recommended. These particular diets aim to attain calorie deficits and thus induce weight loss. Intermittent fasting (IF) is one such diet that focuses more on the timing of calorie consumption. However, there are several methods of achieving this, which are highlighted in this review. IF has been shown to promote weight loss, reduce insulin resistance, improve glycemic control and lower the risk of cardiometabolic diseases. However, little literature is available regarding the use of IF in managing DM. This review intends to elucidate the role of intermittent fasting in preventing and treating DM, including its benefits and limitations. From the various studies reviewed in this article, it can be deduced that intermittent fasting can achieve suitable glycemic targets and weight control.

Effectiveness of Early Time-Restricted Eating for Weight Loss, Fat Loss, and Cardiometabolic Health in Adults With Obesity: A Randomized Clinical Trial

Importance

It is unclear how effective intermittent fasting is for losing weight and body fat, and the effects may depend on the timing of the eating window. This randomized trial compared time-restricted eating (TRE) with eating over a period of 12 or more hours while matching weight-loss counseling across groups.

Objective

To determine whether practicing TRE by eating early in the day (eTRE) is more effective for weight loss, fat loss, and cardiometabolic health than eating over a period of 12 or more hours.

Design, Setting, and Participants

The study was a 14-week, parallel-arm, randomized clinical trial conducted between August 2018 and April 2020. Participants were adults aged 25 to 75 years with obesity and who received weight-loss treatment through the Weight Loss Medicine Clinic at the University of Alabama at Birmingham Hospital.

Interventions

All participants received weight-loss treatment (energy restriction [ER]) and were randomized to eTRE plus ER (8-hour eating window from 7:00 to 15:00) or control eating (CON) plus ER (≥12-hour window).

Main Outcomes and Measures

The co-primary outcomes were weight loss and fat loss. Secondary outcomes included blood pressure, heart rate, glucose levels, insulin levels, and plasma lipid levels.

Results

Ninety participants were enrolled (mean [SD] body mass index, 39.6 [6.7]; age, 43 [11] years; 72 [80%] female). The eTRE+ER group adhered 6.0 (0.8) days per week. The eTRE+ER intervention was more effective for losing weight (-2.3 kg; 95% CI, -3.7 to -0.9 kg; P = .002) but did not affect body fat (-1.4 kg; 95% CI, -2.9 to 0.2 kg; P = .09) or the ratio of fat loss to weight loss (-4.2%; 95% CI, -14.9 to 6.5%; P = .43). The effects of eTRE+ER were equivalent to reducing calorie intake by an additional 214 kcal/d. The eTRE+ER intervention also improved diastolic blood pressure (-4 mm Hg; 95% CI, -8 to 0 mm Hg; P = .04) and mood disturbances, including fatigue-inertia, vigor-activity, and depression-dejection. All other cardiometabolic risk factors, food intake, physical activity, and sleep outcomes were similar between groups. In a secondary analysis of 59 completers, eTRE+ER was also more effective for losing body fat and trunk fat than CON+ER.

Conclusions and Relevance

In this randomized clinical trial, eTRE was more effective for losing weight and improving diastolic blood pressure and mood than eating over a window of 12 or more hours at 14 weeks.

Trial Registration

ClinicalTrials.gov Identifier: NCT03459703.

Is Time-Restricted Eating Safe in the Treatment of Type 2 Diabetes?-A Review of Intervention Studies

Time-restricted eating (TRE) has been shown to improve body weight and glucose metabolism in people at high risk of type 2 diabetes. However, the safety of TRE in the treatment of type 2 diabetes is unclear. We investigated the safety of TRE interventions in people with type 2 diabetes by identifying published and ongoing studies. Moreover, we identified the commonly used antidiabetic drugs and discussed the safety of TRE in people with type 2 diabetes considering the use of these drugs. In addition, we addressed the research needed before TRE can be recommended in the treatment of type 2 diabetes. A literature search was conducted to identify published (MEDLINE PubMed) and ongoing studies (ClinicalTrials.gov) on TRE in people with type 2 diabetes. To assess the usage of antidiabetic drugs and to discuss pharmacodynamics and pharmacokinetics in a TRE context, the most used antidiabetic drugs were identified and analysed. Statistics regarding sale of pharmaceuticals were obtained from MEDSTAT.DK which are based on data from the national Register of Medicinal Product Statistics, and from published studies on medication use in different countries. Four published studies investigating TRE in people with type 2 diabetes were identified as well as 14 ongoing studies. The completed studies suggested that TRE is safe among people with type 2 diabetes. Common antidiabetic drugs between 2010 and 2019 were metformin, insulin, dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists, sulfonylureas, and sodium-glucose cotransporter-2 inhibitors. Existing studies suggest that TRE is not associated with major safety issues in people with type 2 diabetes as long as medication is monitored and adjusted. However, because of low generalisability of the few studies available, more studies are needed to make concrete recommendations regarding efficacy and safety of TRE in people with type 2 diabetes.

Antioxidant Potential, DNA Damage, Inflammation, Glycemic Control and Lipid Metabolism Alteration: A Mediation Analysis of Islamic Sunnah Intermittent Fasting on Cognitive Function among Older Adults with Mild Cognitive Impairment

OBJECTIVES

This study aimed to determine the relationship between oxidative stress, DNA damage, inflammation, and metabolic biomarkers as the mediating factor between Islamic Sunnah intermittent fasting (IF) practice and cognitive function among older adults with mild cognitive impairment (MCI).

DESIGN

This study was a 36 months prospective cohort study.

SETTING

Community-dwelling older participants recruited through a stratified random sampling method from four states representing Malaysia's central, north-west, northeast and southern regions.

PARTICIPANTS

Ninety-nine Malay Muslim older adults (n= 99) aged 60 and above with MCI and no known critical illnesses were included in the current analysis. The participants were divided into regularly practicing IF (r-IF), irregularly practicing IF (i-IF) and not practicing IF (n-IF) groups.

MEASUREMENTS

Fasting venous blood was collected and used to determine the levels of oxidative stress, DNA damage, inflammatory and metabolic biomarkers. Mini-Mental State Examination, Montreal Cognitive Assessment, Rey Auditory Verbal Learning Test, Digit Span and Digit symbol were used to evaluate the cognitive function. Then, the mediation analysis was conducted using a multistep regression model to determine the mediating role of various biomarkers between IF practice and cognitive function.

RESULTS

When comparing the r-IF and n-IF groups, higher SOD activity, lower DNA damage (percentage of DNA in tail), lower CRP levels and higher HDL-cholesterol levels established partial mediation while lower insulin levels established complete mediation between IF practice and better cognitive function. Meanwhile, when comparing the r-IF and i-IF groups, higher SOD activity and lower CRP levels completely mediated the effects of IF practice on better cognitive function.

CONCLUSION

It can be concluded that changes in antioxidant function, DNA damage, inflammation and a limited set of metabolic biomarkers (insulin and HDL cholesterol) may mediate improvements in cognitive function among older participants with MCI who practice Islamic Sunnah IF.

Fasting, Nutrition and Weight Loss: An Approach to Refine Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is considered as one of the most common causes of chronic liver disease. It includes a group of conditions associated with fat deposition in liver cells. Also, NAFLD is strongly associated with obesity and insulin resistance (IR). Until now, there is no pharmacological treatment validated for this disease. Fasting, nutritional intervention, and weight loss can be considered the first line in treating hepatic steatosis. This review is based on the scientific evidence showing the results of these interventions in the past years. The results include fasting and nutritional support for NAFLD treatment in humans. In clinical trials and cohort studies, an increase in hepatic fat content was correlated with a weight loss of at least 7% and a diet resembling the Mediterranean diet (MD) improving hepatic biomarkers and histological regression of NAFLD. Fasting is a dietary approach known to improve the lipid profile in healthy and obese populations by decreasing overall cholesterol, triglycerides, LDL, and increasing HDL. Bariatric surgery helps improve liver fat content in patients with serious health problems due to overweight.

Benefits, mechanisms, and risks of intermittent fasting in metabolic syndrome and type 2 diabetes

One of the emergent nutritional strategies for improving multiple features of cardiometabolic diseases is the practice of intermittent fasting (IF), which consists of alternating periods of eating and fasting. IF can reduce circulating glucose and insulin levels, fat mass, and the risk of developing age-related pathologies. IF appears to upregulate evolution-conserved adaptive cellular responses, such as stress-response pathways, autophagy, and mitochondrial function. IF was also observed to modulate the circadian rhythms of hormones like insulin or leptin, among others, which levels change in conditions of food abundance and deficit. However, some contradictory results regarding the duration of the interventions and the anterior metabolic status of the participants suggest that more and longer studies are needed in order to draw conclusions. This review summarizes the current knowledge regarding the role of IF in the modulation of mechanisms involved in type 2 diabetes, as well as the risks.

Effect of Intermittent Fasting Diet on Glucose and Lipid Metabolism and Insulin Resistance in Patients with Impaired Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis

The question of whether or not intermittent fasting diets improve the clinical indicators of glycolipid metabolism remains unclear. This study systematically reviewed the relevant clinical trials to evaluate the effects of intermittent fasting diet on glucose and lipid metabolism and insulin sensitivity in patients with metabolic syndrome. To evaluate the effect of intermittent fasting diet intervention on patients with disorders of glucose and lipid metabolism, random-effect or fixed-effect meta-analysis models were used to calculate the average difference before and after intermittent fasting diet intervention and the corresponding 95% confidence intervals (CIs). After intermittent fasting diet intervention, in terms of glucose metabolism, fasting blood glucose reduced by 0.15 mmol/L (95% CI: -0.23; -0.06), glycosylated hemoglobin reduced by 0.08 (95% CIs: -0.25; -0.10), insulin plasma levels reduced by 13.25 uUI (95% CIs: -16.69; -9.82), and HOMA-IR decreased by 0.31 on an average (95% CIs: -0.44; -0.19). In addition, BMI decreased by 0.8 kg/m² (95% CIs: -1.32; -0.28), body weight reduced by 1.87 kg (95% CIs: -2.67; -1.07), and the waist circumference decreased by 2.08 cm (95% CIs: -3.06; -1.10). Analysis of lipid metabolism showed that intermittent fasting diet intervention effectively reduced the total cholesterol level by 0.32 mmol/L (95% CIs: -0.60; -0.05), low-density lipoprotein level by 0.22 mmol/L (95% CIs: -0.37; -0.07), and triglyceride level by 0.04 mmol/L (95% CIs: -0.15; -0.07). Intermittent fasting diets have certain therapeutic effects on blood glucose and lipids in patients with metabolic syndrome and significantly improve insulin resistance. It may be considered as an auxiliary treatment to prevent the occurrence and development of chronic diseases.

Effect of time-restricted feeding on body composition and cardio-metabolic risk in middle-aged women in Taiwan

OBJECTIVES

We sought to investigate the effects of time-restricted feeding (TRF) and a traditional weight-loss method on body composition and cardio-metabolic risk factors in middle-aged women.

METHODS

In a single-center, randomized, open-label, parallel-group design, women ages 40 to 65 y with body mass index ≥ 24 kg/m² or waist circumference > 80 cm were recruited. They were guided to a daily low-calorie diet of 1400 kcal and randomly assigned into a TRF group (limit 8 h of eating time and fasting for 16 h) or a non-TRF group (traditional weight-loss method, unrestricted eating time) for 8 wk. Body composition, blood pressure, blood biochemical variables, and insulin resistance status were measured before and after intervention.

RESULTS

Body weight, body mass index, waist circumference, and body fat mass decreased significantly in both groups after 8 wk of intervention (P < 0.05). Body weight decreased more in the TRF group than the non-TRF group (-4.1% ± 2.8% versus -2.4% ± 2.5%; P = 0.012), as did diastolic blood pressure (75.3 ± 11.2 mm Hg versus 70.5 ± 9.4 mm Hg; P = 0.012). There were no statistical differences between the two groups in total cholesterol, triacylglycerols, high- or low-density lipoprotein cholesterol, and fasting insulin level. However, fasting glucose and insulin resistance status increased significantly for the TRF group after the intervention (respectively, 88.3 ± 7.6 mg/dL versus 92.6 ± 9.6 mg/dL, P = 0.003; 1.7 ± 0.7 versus 2.1 ± 1.0, P = 0.048).

CONCLUSION

The weight loss and reduction in diastolic blood pressure using the TRF method were better than with the traditional weight-loss method. However, this method may increase fasting glucose levels and adverse insulin resistance status.

Intermittent fasting for obesity and related disorders: unveiling myths, facts, and presumptions

Intermittent fasting (IF) is an increasingly popular method of weight loss, as an alternative to daily caloric restriction (DCR). Several forms of IF exist, such as alternate-day fasting or time-restricted feeding regimens. Some of its proponents claim several health benefits unrelated to caloric restriction or weight loss, which rely mainly on animal models. Although several studies published in the last few years confirm that IF can be a useful and safe therapeutical option for obesity and related disorders, no superiority to conventional caloric restriction diets have emerged. There are still several questions left answered. In this Review, we discuss some of the claims, unveiling myths, facts, and presumptions about several models of IF. The focus of this article is obesity, but there is a brief discussion of the potential benefits of IF on overall human health.

Fasting drives the metabolic, molecular and geroprotective effects of a calorie-restricted diet in mice

Calorie restriction (CR) promotes healthy ageing in diverse species. Recently, it has been shown that fasting for a portion of each day has metabolic benefits and promotes lifespan. These findings complicate the interpretation of rodent CR studies, in which animals typically eat only once per day and rapidly consume their food, which collaterally imposes fasting. Here we show that a prolonged fast is necessary for key metabolic, molecular and geroprotective effects of a CR diet. Using a series of feeding regimens, we dissect the effects of calories and fasting, and proceed to demonstrate that fasting alone recapitulates many of the physiological and molecular effects of CR. Our results shed new light on how both when and how much we eat regulate metabolic health and longevity, and demonstrate that daily prolonged fasting, and not solely reduced caloric intake, is likely responsible for the metabolic and geroprotective benefits of a CR diet.