Time-Restricted Eating, Intermittent Fasting, and Fasting-Mimicking Diets in Weight Loss

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.

Lactobacillus plantarum L11 and Lactobacillus reuteri LR: Ameliorate Obesity via AMPK Pathway

OBJECTIVES

The purpose of this study was to find the potential mechanism of two Lactobacillus (Lactobacillus plantarum L11 and Lactobacillus reuteri LR) on ameliorating obesity, including lipid metabolism and gut microbiota. The two isolates have been studied to have good characterization in vitro, but in vivo studies in modulating lipid metabolism and gut microbiota were not studied.

METHODS

In this study, mice with HFD supplemented with L11 or LR exhibited slower obesity progression, including reduced weight gain, abdominal fat accumulation, liver damage, inflammation, and adipose lesions.

RESULTS

Total cholesterol (TC) and triglycerides (TG) in the serum were significantly reduced (p < 0.01). The inflammatory marker interleukin-6 (IL-6) notably decreased (p < 0.05). Both Lactobacillus strains altered the gut microbiota composition, increasing the relative abundance of Alistipes and Lactobacillus, while L11 also raised Lachnospiraceae abundance. Results of the Western blot analysis showed that L11 and LR influenced the PPAR and AMPK pathways.

CONCLUSIONS

L11 and LR can effectively reduce obesity by modulating gut microbiota and activating the PPAR-AMPK pathway, leading to decreased liver injury and systemic inflammation in mice fed with an HFD. In the future, the two probiotics may provide a new way for clinically ameliorating obesity on human beings.

Adherence and Retention in Early or Late Time-Restricted Eating: A Narrative Review of Randomized Controlled Trials

Time-restricted eating (TRE) is a form of intermittent fasting that involves reducing the time-period in which food is typically consumed daily. While TRE is known to induce health benefits, particularly for adults with obesity, there is currently debate about whether the time of day in which food is consumed also contributes to the health benefits of TRE. Early TRE (eTRE) and late TRE (lTRE) are subtypes of TRE that involve consuming food and caloric beverages either in the early or later part of the day. A growing body of literature indicates that eTRE may offer additional health benefits compared with lTRE. An important and unanswered question, however, is whether most adults can adhere to this type of eating pattern and whether adherence and retention differ between eTRE and lTRE. This narrative review compared adherence and retention in studies that implemented either eTRE or lTRE in adults for 8 weeks or longer. Five databases were searched, and 10 studies met our eligibility criteria. The key finding was that participants had high and comparable levels of adherence and retention in both eTRE and lTRE interventions. Specifically, the mean adherence rate was 81.4% for eTRE and 82.3% for lTRE, while the mean retention rate was 81% for eTRE and 85.8% for lTRE in eligible studies. Thus, the findings support the feasibility of both approaches. The lowest adherence and retention rates occurred in studies in which either eTRE or lTRE regimens were combined with other dietary interventions. Notably, the duration of the eating window did not seem to negatively affect adherence and retention rates for either eTRE or lTRE. More research is warranted to determine the influence of other factors, such as age and study location, on adherence to and retention of both eTRE and lTRE interventions.

Dietary Modification Patterns and Interventions Among Weight Loss Seekers in Tamil Nadu, South India: A Cross-Sectional Analysis of Intermittent Fasting and Alternative Dietary Approaches

Background The escalating global obesity epidemic requires comprehensive investigations for effective weight management strategies. Understanding the patterns, barriers, and facilitators of dietary interventions is crucial for developing effective weight management protocols. This research aims to assess dietary modification interventions among weight loss subjects in Tamilnadu, South India. Specific objectives included evaluating various weight loss interventions, analyzing dietary patterns adopted by subjects, and examining characteristics, barriers, and facilitators associated with specific dietary modification approaches. Methodology A cross-sectional study was conducted among 432 participants from Tamilnadu, South India. The research employed a comprehensive data collection approach, gathering information on demographic characteristics, anthropometric measurements, dietary modification patterns, and intervention outcomes. Participants were categorized based on their chosen dietary interventions, particularly distinguishing between intermittent fasting and alternative dietary approaches. The study systematically evaluated various parameters, including regular adherence, physiological effects, psychological impacts, and barriers to maintenance. Statistical analysis utilized chi-square and Fischer's exact tests for categorical variables, while independent t-tests were employed for continuous variables. Results This study encompassed 432 participants, with demographically diverse participants characterized by a predominance of urban residents (295, 68.3%), highly educated individuals (383, 88.6%), and students (190, 44%). The mean age was 27.93 years, with a mean body mass index of 25.21 kg/m2. Regarding dietary intervention objectives, the study revealed that 289 (66.9%) were not engaged in any healthcare intervention, while 102 (23.6%) pursued intermittent fasting and 41 (9.5%) adopted alternative dietary strategies such as Paleo and ketogenic diets. Among participants implementing dietary modifications, the mean intervention duration was 5.21 months, ranging from half a month to 60 months. Intermittent fasting participants exhibited statistically significant characteristics, including a younger mean age (27.09 years) compared with alternative diet groups (37.37 years). Notably, 73 (71.6%) reported significant weight loss, with 69 (67.6%) experiencing weight regain during non-adherence. Psychological and physiological benefits were prominently observed, with 73 (71.6%) reporting mood improvements, 71 (69.6%) experiencing enhanced concentration, and 72 (70.6%) noting improved bowel habits. Barriers to dietary modifications included timing challenges (50, 49%), family mealtime conflicts (43, 42.2%), and work schedule interruptions (39, 38.2%). Conclusion The research provides comprehensive insights into dietary modification patterns among young Indian adults, highlighting intermittent fasting's potential as an effective weight management strategy. The findings underscore the complex interplay between dietary choices, individual characteristics, and holistic health outcomes. While demonstrating promising weight loss and cognitive benefits, the study emphasizes the necessity of personalized, context-sensitive nutritional interventions. These insights contribute significantly to understanding dietary modification dynamics and inform the development of more effective, tailored weight management strategies.

Caloric restriction mimetics: Pinostilbene versus resveratrol regarding SIRT1 and SIRT6 interaction

PURPOSE

Caloric restriction (CR), the permanent or periodic reduction of caloric intake, is a dietary strategy that promotes longevity and healthspan, yielding multiple beneficial effects, such as improved insulin sensitivity and mitochondrial function, decreased body weight, and mitigation of cardiometabolic risk factors. The purpose of our study was the in silico and in vitro assessment of the effects exerted by pinostilbene on SIRT1 and SIRT6 compared to those of resveratrol, a known activator of these enzymes.

MATERIALS AND METHODS

Molecular docking was carried out to determine the interactions with SIRT1 and SIRT6 and, further, the effect of pinostilbene on their activity was tested in vitro to evaluate if it parallels resveratrol's effects regarding SIRT activation.

RESULTS

Molecular docking indicates that resveratrol and pinostilbene bind similarly to SIRT6, while pinostilbene may be able to activate SIRT1 more efficiently than resveratrol. In vitro activity assays showed that while both resveratrol and pinostilbene activate SIRT1 and SIRT6, the concentration-dependent effects differ. For resveratrol, a greater effect was observed at the medium concentration (25 ​μM), whereas pinostilbene showed a more pronounced activation at the lowest concentration (5 ​μM).

CONCLUSIONS

Our results offer a glimpse into the structural features and interactions of pinostilbene and resveratrol with SIRT1 and SIRT6, contributing to understanding their potential roles in various cellular processes regulated by SIRT.

Noradrenergic Projections from the Locus Coeruleus to the Medial Prefrontal Cortex Enhances Stress Coping Behavior in Mice Following Long-Term Intermittent Fasting

Intermittent fasting has been shown to alleviate stress, anxiety, and depressive symptoms. Although noradrenaline, also known as norepinephrine (NE), is implicated in stress regulation, the dynamics of NE release and the associated neural pathways during stress coping behaviors in fasting mice remain poorly understood. In this study, we employed the forced swimming test (FST) to evaluate the effects of intermittent fasting on stress coping behavior in mice. Our results demonstrate that mice subjected to long-term intermittent fasting exhibited significantly more active coping behaviors in the FST compared to control mice. In contrast, acute fasting did not produce similar effects. Using the fluorescent GRAB-NE sensor to measure NE release with sub-second temporal resolution during the FST, we found that intermittent fasting modulates the locus coeruleus-medial prefrontal cortex (LC-mPFC) pathway, which underlies these behavioral adaptations. Moreover, chemogenetic activation of LC-mPFC projections strongly promoted active coping in the FST. These findings suggest that enhanced LC-mPFC activity mediates the increased active coping behavior observed in fasting mice. This study provides new insights into the neural mechanisms through which intermittent fasting may ameliorate depressive-like behaviors, offering potential therapeutic targets for stress-related disorders.

Prolonged Water-Only Fasting Followed by a Whole-Plant-Food Diet Is a Potential Long-Term Management Strategy for Hypertension and Obesity

Objective: This single-arm, pre-post interventional trial (clinicaltrials.gov, NCT04515095) investigates the safety, feasibility, and potential effectiveness of prolonged water-only fasting followed by a whole-plant-food diet in the long-term management of hypertension and other cardiometabolic disorders. Methods: Safety was assessed based on adverse events (AEs) that were recorded according to Common Terminology Criteria for Adverse Events (CTCAE) v5.0. Feasibility was assessed based on retention rate, ability to complete minimal fast length, and intervention acceptability. Twenty-nine participants with stage 1 and 2 hypertension and without type 2 diabetes were enrolled from a residential fasting center. Results: Study retention was 100% at the end of the refeed and 93% at the six-week follow-up visit. Median (range) fasting and refeeding duration were 11 (7-40) and 5 (3-17) days, respectively, and 90% of participants were able to complete at least 7 days of fasting. The majority of AEs were mild (grade 1) and transient and there were no higher-grade or serious AEs. At the end of the intervention, median systolic/diastolic blood pressure had normalized to below 130/80 mmHg, body weight reduced by >5%, and anti-hypertensive medication was completely discontinued. These results were sustained for at least six weeks and potentially up to one year. Conclusions: Our data suggest that the intervention may be a feasible, well-tolerated, low-risk option for lowering and managing high blood pressure, excess body weight, and other cardiometabolic disorders in people with stage 1 and 2 hypertension.

The effect of different dietary restriction on weight management and metabolic parameters in people with type 2 diabetes mellitus: a network meta-analysis of randomized controlled trials

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a globally prevalent chronic condition. Individuals with T2DM are at increased risk of developing complications associated with both macrovascular and microvascular pathologies. These comorbidities reduce patient quality of life and increase mortality. Dietary restriction is a principal therapeutic approach for managing T2DM. This study assessed the effects of various dietary regimens on body weight and metabolic profiles in T2DM patients, aiming to determine the most beneficial interventions for enhancing clinical outcomes and overall well-being.

METHODS

We conducted a literature search in PubMed, Embase, and Web of Science from 2003 to April 15, 2024. The risk of bias was assessed via the Revised Cochrane risk-of-bias tool for randomized trials (RoB2). The certainty of the evidence was appraised via the confidence in network meta-analysis (CINeMA) framework. Intermittent fasting (IF) was directly compared with continuous energy restriction (CER) via Review Manager 5.4. Network meta-analysis was statistically assessed via R Studio 4.3.3 and STATA 14.0.

RESULTS

Eighteen studies involving 1,658 participants were included. The network meta-analysis indicated that intermittent energy restriction, the twice-per-week fasting, time-restricted eating, fasting-mimicking diets (FMD), and CER interventions were more effective than conventional diets. Direct comparisons revealed that IF was as effective as CER for reducing glycated haemoglobin A1c, body weight, and body mass index. The results of the cumulative ranking analysis demonstrated that FMD had the greatest combined intervention effect, followed by TRE in terms of overall effectiveness.

CONCLUSIONS

Both IF and CER exert positive influences on weight control and metabolic profile enhancement in individuals with T2DM, with FMD as part of IF demonstrating the greatest impact. To substantiate these findings, more rigorous randomized controlled trials that directly compare the effects of the different IF regimens with one another and with the CER regimen are needed.

Try not to think about food: An association between fasting, binge eating and food cravings

BACKGROUND

When individuals follow a diet or limit their food intake, they activate cognitive restraint, which is defined as a mental effort to restrict dietary behavior with the goal of losing weight. As an example, fasting has also been associated with the recruitment of cognitive restraint, but further research is needed to fully understand its underlying mechanisms.

AIMS

The aim of this study was to examine the relationship between the duration of fasting and disordered eating, such as food cravings, binge eating, and potential changes in eating habits.

METHODS

An online survey was conducted among 853 first-semester university students to investigate their fasting practices and frequency over a three-month period prior to data collection. Participants who were on diets were excluded (n=214). After controlling the sample for biases, a comparison was made between 89 fasters and 369 non-fasters. The study compared levels of cognitive restraint, binge eating, food cravings, and consumption of 'forbidden' foods. A Poisson model was used to examine the association between hours of fasting and disordered eating traits. In the context of this study, the rate ratio was used to examine the relationship between fasting hours and disordered eating characteristics, such as binge eating and food cravings.

RESULTS

The study found that fasters experienced an increase in food cravings and binge eating. However, fasters consumed fewer bread slices than non-fasters. The rate ratio of fasting hours practiced is 115% higher among binge eaters (RR 2.15; CI95% 1.70-2.73) compared to those who did not binge. The rate ratio of fasting hours is 29% higher in participants with moderate binge eating (RR 1.29; CI95% 1.05-1.59), increasing to 140% (RR 2.40; CI95% 1.86-3.11) in people with severe binge eating. As for food cravings (state), the rate ratio was 2% higher (RR 1.02; CI 95% 1.01-1.03) for each increase in the unit of the scale.

CONCLUSIONS

Our study has indicated that fasting is positively associated with increased levels of binge eating and food cravings.

Effect of Time-Restricted Eating on Circulating Levels of IGF1 and Its Binding Proteins in Obesity: An Exploratory Analysis of a Randomized Controlled Trial

Obesity is associated with alterations in circulating IGF1, IGF1-binding proteins (IGFBPs), insulin, inflammatory markers, and hormones implicated in cardiovascular disease, diabetes, cancer, and aging. However, the effects of 4 and 6 h time-restricted eating (TRE) on circulating IGF1 and IGFBPs is uncertain.

OBJECTIVE

This study aimed to investigate the effects of TRE on plasma IGF1, IGFBP1, IGFBP2, and IGFBP3, and whether these effects were mediated by weight loss or body composition changes. Insulin sensitivity, glucose control, adipokines, and inflammatory markers were also examined.

DESIGN

An exploratory analysis of an 8-week randomized controlled trial implementing a daily TRE intervention was carried out.

PARTICIPANTS/SETTING

This study was conducted at the University of Illinois at Chicago in 2019. Participants with obesity were randomized to 4 or 6 h TRE (n = 35) or a control (n = 14) group. Plasma biomarkers were measured by ELISA at baseline and week 8. In a sub-analysis, participants were stratified into higher- (>3.5%) and lower- (≤3.5%) weight-loss groups.

INTERVENTION

Participants fasted daily from 7 p.m. to 3 p.m. in the 4 h TRE group (20 h) and from 7 p.m. to 1 p.m. in the 6 h TRE group (18 h), followed by ad libitum eating for the remainder of the day. Controls received no dietary recommendations.

MAIN OUTCOME MEASURES

IGF1, IGFBPs, hsCRP, and adipokines were the main outcome measures of this analysis.

STATISTICAL ANALYSIS

Repeated measures ANOVA and mediation analysis were conducted.

RESULTS

Body weight significantly decreased with TRE (-3.6 ± 0.3%), contrasting with controls (+0.2 ± 0.5%, p < 0.001). Significant effects of TRE over time were observed on plasma IGFBP2, insulin, HOMA-IR, and 8-isoprostane levels, without affecting other biomarkers. In the sub-analysis, IGFBP2 increased while leptin and 8-isoprostane decreased significantly only in the "higher weight loss" subgroup. Changes in insulin and HOMA-IR were related to TRE adherence.

CONCLUSIONS

Eight-week daily 4 to 6 h TRE did not affect IGF1, IGFBP1, or IGFBP3 levels but improved insulin, HOMA-IR, and 8-isoprostane. IGFBP2 increased and leptin decreased when weight loss exceeded 3.5% of baseline.

Approach to the Treatment of Children and Adolescents with Obesity

Pediatric obesity continues to be an omnipresent disease; 1 in 5 children and adolescents have obesity in the United States. The comorbidities associated with youth-onset obesity tend to have a more severe disease progression in youth compared to their adult counterparts with the same obesity-related condition. A comorbidity of focus in this study is metabolism-associated steatotic liver disease (MASLD), which has rapidly evolved into the most common liver disease seen in the pediatric population. A direct association exists between the treatment of MASLD and the treatment of pediatric obesity. The current evidence supports that obesity treatment is safe and effective.

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.

Treatment of mice with maternal intermittent fasting to improve the fertilization rate and reproduction

Maternal intermittent fasting (MIF) can have significant effects on several tissue and organ systems of the body, but there is a lack of research on the effects on the reproductive system. So, the aim of our study was to analyze the effects of MIF on fertility. B6C3F1Crl (C57BL/6N × C3H/HeN) male and female mice were selected for the first part of the experiments and were analyzed for body weight and fat weight after administration of the MIF intervention, followed by analysis of sperm counts and activation and embryo numbers. Subsequently, two strains of mice, C57BL/6NCrl and BALB/cJRj, were selected and administered MIF to observe the presence or absence of vaginal plugs for the purposes of mating success, sperm and oocyte quality, pregnancy outcome, fertility status and in vitro fertilization (IVF). Our results showed a significant reduction in body weight and fat content in mice receiving MIF intervention in B6C3F1Crl mice. Comparing the reproduction of the two strains of mice. However, the number of litters was increased in all MIF interventions in C57BL/6NCrl, but not statistically significant. In BALB/cJRj, there was a significant increase in the number of pregnant females as well as litter size in the MIF treatment group, as well as vaginal plugs, and IVF. There was also an increase in sperm activation and embryo number and the MIF intervention significantly increased sperm count and activation. Our results suggest that MIF interventions may be beneficial for reproduction in mice.

Eating away cancer: the potential of diet and the microbiome for shaping immunotherapy outcome

The gut microbiome (GMB) plays a substantial role in human health and disease. From affecting gut barrier integrity to promoting immune cell differentiation, the GMB is capable of shaping host immunity and thus oncogenesis and anti-cancer therapeutic response, particularly with immunotherapy. Dietary patterns and components are key determinants of GMB composition, supporting the investigation of the diet-microbiome-immunity axis as a potential avenue to enhance immunotherapy response in cancer patients. As such, this review will discuss the role of the GMB and diet on anti-cancer immunity. We demonstrate that diet affects anti-cancer immunity through both GMB-independent and GMB-mediated mechanisms, and that different diet patterns mold the GMB's functional and taxonomic composition in distinctive ways. Dietary modulation therefore shows promise as an intervention for improving cancer outcome; however, further and more extensive research in human cancer populations is needed.

Does time-restricted eating add benefits to calorie restriction? A systematic review

OBJECTIVE

A growing body of evidence has supported the health benefits of extended daily fasting, known as time-restricted eating (TRE); however, whether the addition of TRE enhances the known benefits of calorie restriction (CR) remains unclear.

METHODS

PubMed, Scopus, the Cochrane Library, and Google Scholar were searched through April 2023. This systematic review includes randomized controlled trials (RCTs) that compared CR + TRE with CR alone in energy-matched conditions of at least 8 weeks in duration that assessed changes in body weight and cardiometabolic disease risk factors in adults with overweight and/or obesity.

RESULTS

Seven studies were identified (n = 579). Two studies reported greater weight loss and reductions in diastolic blood pressure with CR + TRE compared with CR alone after 8 to 14 weeks, whereas one study reported greater improvements in triglycerides and glucose tolerance with CR + TRE (3 days/week) compared with CR alone following 26 weeks. One study reported significant increases in homeostatic model assessment of insulin resistance (HOMA-IR) levels with CR + TRE versus CR alone after 8 weeks. There were no statistically significant differences in any other outcome variable between the two interventions.

CONCLUSIONS

The addition of TRE to CR regimens resulted in greater weight loss and improvements in cardiometabolic risk factors in some studies; however, the majority of studies did not find additional benefits.

Underrated aspects of a true Mediterranean diet: understanding traditional features for worldwide application of a "Planeterranean" diet

Over the last decades, the Mediterranean diet gained enormous scientific, social, and commercial attention due to proven positive effects on health and undeniable taste that facilitated a widespread popularity. Researchers have investigated the role of Mediterranean-type dietary patterns on human health all around the world, reporting consistent findings concerning its benefits. However, what does truly define the Mediterranean diet? The myriad of dietary scores synthesizes the nutritional content of a Mediterranean-type diet, but a variety of aspects are generally unexplored when studying the adherence to this dietary pattern. Among dietary factors, the main characteristics of the Mediterranean diet, such as consumption of fruit and vegetables, olive oil, and cereals should be accompanied by other underrated features, such as the following: (i) specific reference to whole-grain consumption; (ii) considering the consumption of legumes, nuts, seeds, herbs and spices often untested when exploring the adherence to the Mediterranean diet; (iii) consumption of eggs and dairy products as common foods consumed in the Mediterranean region (irrespectively of the modern demonization of dietary fat intake). Another main feature of the Mediterranean diet includes (red) wine consumption, but more general patterns of alcohol intake are generally unmeasured, lacking specificity concerning the drinking occasion and intensity (i.e., alcohol drinking during meals). Among other underrated aspects, cooking methods are rather simple and yet extremely varied. Several underrated aspects are related to the quality of food consumed when the Mediterranean diet was first investigated: foods are locally produced, minimally processed, and preserved with more natural methods (i.e., fermentation), strongly connected with the territory with limited and controlled impact on the environment. Dietary habits are also associated with lifestyle behaviors, such as sleeping patterns, and social and cultural values, favoring commensality and frugality. In conclusion, it is rather reductive to consider the Mediterranean diet as just a pattern of food groups to be consumed decontextualized from the social and geographical background of Mediterranean culture. While the methodologies to study the Mediterranean diet have demonstrated to be useful up to date, a more holistic approach should be considered in future studies by considering the aforementioned underrated features and values to be potentially applied globally through the concept of a "Planeterranean" diet.

Ketone bodies in cell physiology and cancer

Ketogenic diets (KDs), fasting, or prolonged physical activity elevate serum ketone bodies (KBs) levels, providing an alternative fuel source for the brain and other organs. However, KBs play pleiotropic roles that go beyond their role in energy production. KBs can act as signaling metabolites, influence gene expression, proteins' posttranslational modifications (PTMs), inflammation, and oxidative stress. Here, we explore the impact of KBs on mammalian cell physiology, including aging and tissue regeneration. We also concentrate on KBs and cancer, given the extensive evidence that dietary approaches inducing ketosis, including fasting-mimicking diets (FMDs) and KDs, can prevent cancer and affect tumor progression.

Various types of fasting diet and possible benefits in nonalcoholic fatty liver: Mechanism of actions and literature update

Non-alcoholic fatty liver disease (NAFLD) is one of the major causes of chronic liver injury, affecting around one-fourth of the general population across the world. Several important pathophysiological mechanisms underlying NAFLD include oxidative stress, inflammation, liver fibrosis, and apoptosis. Currently, therapeutic approaches are not ideal for managing NAFLD, thus new approaches and treatments are still needed. Over the last two decades, various fasting protocols have been explored to reduce body weight and improve metabolic disorders. In this review, we provide updated literature that supports fasting regimens for subjects with NAFLD and describes underlying mechanisms of action. We suggest that fasting regimens may modulate NAFLD via several mechanisms, including changes in gut microbiota, hepatic arginase, hepatic autophagy, inflammatory responses, liver functional enzymes and hepatic steatosis, fibroblast growth factors signaling, white adipose tissue browning, adipokines, circadian rhythms, lipid profiles, and body composition.

Intermittent Fasting: Does It Affect Sports Performance? A Systematic Review

Intermittent fasting is one of the most popular types of diet at the moment because it is an effective nutritional strategy in terms of weight loss. The main objective of this review is to analyze the effects that intermittent fasting has on sports performance. We analyzed physical capacities: aerobic capacity, anaerobic capacity, strength, and power, as well as their effect on body composition. For this, a bibliographic search was carried out in several databases where 25 research articles were analyzed to clarify these objectives. Inclusion criteria: dates between 2013 and present, free full texts, studies conducted in adult human athletes, English and/or Spanish languages, and if it has been considered that intermittent fasting is mainly linked to sports practice and that this obtains a result in terms of performance or physical capacities. This review was registered in PROSPERO with code ref. 407024, and an evaluation of the quality or risk of bias was performed. After this analysis, results were obtained regarding the improvement of body composition and the maintenance of muscle mass. An influence of intermittent fasting on sports performance and body composition is observed. It can be concluded that intermittent fasting provides benefits in terms of body composition without reducing physical performance, maintenance of lean mass, and improvements in maximum power. But despite this, it is necessary to carry out new studies focusing on the sports field since the samples have been very varied. Additionally, the difference in hours of intermittent fasting should be studied, especially in the case of overnight fasting.

The Effects of a High-Carbohydrate versus a High-Fat Shake on Biomarkers of Metabolism and Glycemic Control When Used to Interrupt a 38-h Fast: A Randomized Crossover Study

This study aimed to determine the impact of various fast-interrupting shakes on markers of glycemic control including glucose, β-hydroxybutyrate (BHB), insulin, glucagon, GLP-1, and GIP. Twenty-seven sedentary adults (twelve female, fifteen male) with overweight or obesity completed this study. One condition consisted of a 38-h water-only fast, and the other two conditions repeated this, but the fasts were interrupted at 24 h by either a high carbohydrate/low fat (HC/LF) shake or an isovolumetric and isocaloric low carbohydrate/high fat (LC/HF) shake. The water-only fast resulted in 135.3% more BHB compared to the HC/LF condition (p < 0.01) and 69.6% more compared to the LC/HF condition (p < 0.01). The LC/HF condition exhibited a 38.8% higher BHB level than the HC/LF condition (p < 0.01). The area under the curve for glucose was 14.2% higher in the HC/LF condition than in the water condition (p < 0.01) and 6.9% higher compared to the LC/HF condition (p < 0.01), with the LC/HF condition yielding 7.8% more glucose than the water condition (p < 0.01). At the 25-h mark, insulin and glucose-dependent insulinotropic polypeptide (GIP) were significantly elevated in the HC/LF condition compared to the LC/HF condition (p < 0.01 and p = 0.02, respectively) and compared to the water condition (p < 0.01). Furthermore, insulin, GLP-1, and GIP were increased in the LC/HF condition compared to the water condition at 25 h (p < 0.01, p = 0.015, and p < 0.01, respectively). By the 38-h time point, no differences were observed among the conditions for any of the analyzed hormones. While a LC/HF shake does not mimic a fast completely, it does preserve some of the metabolic changes including elevated BHB and glucagon, and decreased glucose and insulin compared to a HC/LF shake, implying a potential for improved metabolic health.

Intermittent Fasting on Neurologic Diseases: Potential Role of Gut Microbiota

As the global population ages, the prevalence of neurodegenerative diseases is surging. These disorders have a multifaceted pathogenesis, entwined with genetic and environmental factors. Emerging research underscores the profound influence of diet on the development and progression of health conditions. Intermittent fasting (IF), a dietary pattern that is increasingly embraced and recommended, has demonstrated potential in improving neurophysiological functions and mitigating pathological injuries with few adverse effects. Although the precise mechanisms of IF's beneficial impact are not yet completely understood, gut microbiota and their metabolites are believed to be pivotal in mediating these effects. This review endeavors to thoroughly examine current studies on the shifts in gut microbiota and metabolite profiles prompted by IF, and their possible consequences for neural health. It also highlights the significance of dietary strategies as a clinical consideration for those with neurological conditions.

Impact of 8-hour time-limited eating on sleep in adolescents with obesity

STUDY OBJECTIVES

The relationship between time-limited eating (TLE) and sleep quality is a topic of growing interest in the field of chronobiology. Data in adult cohorts shows that TLE may improve sleep quality, but this has not been evaluated in adolescents. The aim of this secondary analysis was to (1) examine the impact of 8-hour TLE on sleep parameters in youth with obesity and (2) explore if there was any association between sleep patterns and glycemic profiles.

METHODS

Adolescents with obesity were randomized into one of three groups: 8-hour TLE (participants self-selected their eating window) + real-time continuous glucose monitor, 8-hour TLE + blinded continuous glucose monitor, or a prolonged eating window. In the primary analysis, it was found that participants in the real-time continuous glucose monitor group + 8-hour TLE group did not access their continuous glucose monitor data and thus for this analysis the two TLE groups were combined and only completers who had available Pittsburgh Sleep Quality Index (PSQI) data at all three time points were included. Participants completed the PSQI at baseline, week 4, and week 12. Mixed-effects generalized linear regression models were utilized to examine the change in PSQI score and assess association between glycemic variability and PSQI total score overtime by intervention arm.

RESULTS

The median PSQI total score for the TLE groups (n = 27) was 6 at week 0 (interquartile range = 5 to 10) and 5 at week 12 (interquartile range = 2 to 7). There was no significant difference in the change in total PSQI score or sleep latency between TLE and control over the study period (P > .05). There was no association between PSQI score and change in weight or glycemic profile between groups (all P values > 0.05).

CONCLUSIONS

These results suggest that in adolescents with obesity, an 8-hour TLE approach did not negatively impact sleep quality or efficiency when compared to a prolonged eating window. The potential effects of TLE on sleep should be further investigated in larger randomized trials.

CITATION

Jayakumr A, Gillett ES, Wee CP, Kim A, Vidmar AP. Impact of 8-hour time-limited eating on sleep in adolescents with obesity. J Clin Sleep Med. 2023;19(11):1941-1949.

Time-restricted eating with calorie restriction on weight loss and cardiometabolic risk: a systematic review and meta-analysis

The effect of time-restricted eating (TRE) has been summarized in previous studies, but its benefits in combination with calorie restriction (CR) still need to be determined. The present meta-analysis aimed to evaluate the efficacy of TRE with CR on weight loss and cardiometabolic risk. PubMed, Embase, Cochrane Library, and gray literature databases were searched from inception to October 18, 2022, for potential randomized controlled trial (RCT) studies based on predefined inclusion and exclusion criteria. Body weight and other cardiometabolic risk factors were described as weighted mean difference (WMD) with a 95% confidence interval (CI). Eight RCTs involving 579 participants were enrolled in the present analysis. The pooled results showed that TRE with CR reduced the body weight, fat mass, and waist circumference significantly (WMD: -1.40, 95% CI: -1.81 to -1.00, and I2: 0%; WMD: -0.73, 95% CI: -1.39 to -0.07, and I2: 0%; WMD: -1.87, 95% CI: -3.47 to -0.26, and I2: 67.25%, respectively). However, compared with CR alone, TRE plus CR exhibited no significant benefit on the blood pressure, glucose profile, and lipid profile. Subgroup analysis suggested that early TRE is more effective in weight loss (WMD: -1.42, 95% CI: -1.84 to -1.01, and I2: 0%) and improving fat mass (WMD: -1.06, 95% CI: -1.91 to -0.22, and I2: 0%) than delayed or broader TRE when combined with CR. Although the combination of TRE and CR can effectively decrease body weight, fat mass, and waist circumference, the long-term effects, particularly those on cardiometabolic risk in participants with chronic cardiovascular disease and diabetes, remain to be explored.

Effect of Oleoylethanolamide-Based Dietary Supplement on Systemic Inflammation in the Development of Alimentary-Induced Obesity in Mice

The complex effect of oleoylethanolamide-based dietary supplement (OEA-DS) was studied in a model of diet-induced obesity in mice. Physiological, biochemical, and immunohistochemical methods were used to reveal differences in the changes in the weight of experimental animals, morphological changes in the spleen tissues, and changes in the cytokine expression profile in the spleen, blood plasma, and macrophage cell culture. First, it is shown that a hypercaloric diet high in carbohydrates and cholesterol led to the development of systemic inflammation, accompanied by organ morphological changes and increased production of proinflammatory cytokines. In parallel, the use of OEA-DS reduced the intensity of cellular inflammatory reactions, accompanied by a decrease in markers of cellular inflammation and proliferation, such as CD68, Iba-1, and Ki67 in the spleen tissue, and stabilized the level of proinflammatory cytokines (IL-1β, IL-6, TNFα) both in animals and in cell culture. In addition, in the macrophage cell culture (RAW264.7), it was shown that OEA-DS also suppressed the production of reactive oxygen species and nitrites in LPS-induced inflammation. The results of this study indicate the complex action of OEA-DS in obesity, which includes a reduction of systemic inflammation.

Why does type 2 diabetes mellitus impair weight reduction in patients with obesity? A review

Background

A common adiposopathic complication of obesity is type 2 diabetes mellitus. Healthful weight reduction in patients with obesity can improve glucose metabolism and potentially promote remission of type 2 diabetes mellitus. However, weight-reduction in patients with increased adiposity is impaired among patients with type 2 diabetes mellitus compared to patients without diabetes mellitus.

Methods

Data for this review were derived from PubMed and applicable websites.

Results

Among patients with increased body fat, the mechanisms underlying impaired weight reduction for those with type 2 diabetes mellitus are multifactorial, and include energy conservation (i.e., improved glucose control and reduced glucosuria), hyperinsulinemia (commonly found in many patients with type 2 diabetes mellitus), potential use of obesogenic anti-diabetes medications, and contributions from multiple body systems. Other factors include increased age, sex, genetic/epigenetic predisposition, and obesogenic environments.

Conclusions

Even though type 2 diabetes mellitus impairs weight reduction among patients with increased adiposity, clinically meaningful weight reduction improves glucose metabolism and can sometimes promote diabetes remission. An illustrative approach to mitigate impaired weight reduction due to type 2 diabetes mellitus is choosing anti-diabetes medications that increase insulin sensitivity and promote weight loss and deprioritize use of anti-diabetes medications that increase insulin exposure and promote weight gain.

Umbrella review of time-restricted eating on weight loss, fasting blood glucose, and lipid profile

CONTEXT

A growing number of systematic reviews with meta-analyses have examined the effectiveness of time-restricted eating (TRE) in reducing weight and improving fasting blood glucose and lipid profiles. However, mixed results have been found, and its effectiveness remains uncertain.

OBJECTIVE

This umbrella review aimed to summarize systematic reviews that (1) examine the effects of TRE on weight loss, fasting blood glucose, total cholesterol, triglycerides, high-density-lipoprotein cholesterol (HDL-C) and low-density-lipoprotein cholesterol (LDL-C) in individuals with overweight and obesity; and (2) compare the effect sizes on these outcomes between conventional TRE and Ramadan fasting.

DATA SOURCES

A total of 11 databases were searched from inception until March 11, 2022.

DATA EXTRACTION

Two independent reviewers performed article selection, data extraction, and quality assessment.

DATA ANALYSIS

Seven systematic reviews with 30 unique meta-analyses involving 7231 participants from 184 primary studies were included. The quality of each review was evaluated as moderate (14.3%) or critically low (85.7%) according to the Assessment of Multiple Systematic Reviews 2. The degree of overlap was rated as slight for all outcomes (corrected cover area = 1.04%-4.27%). Meta-analyses at the meta-data level suggest that TRE is beneficial for reducing weight (P = .006) and fasting blood glucose (P < .01). Meta-analyses at the primary study level suggest that the effect on LGL-C was significant (P = .03). Subgroup analyses revealed greater effects in lowering fasting blood glucose, total cholesterol, and LDL-C from Ramadan fasting than from conventional TRE. The credibility of evidence was rated as suggestive (3.3%), weak (36.7%) or nonsignificant (60%) using a classification method.

CONCLUSION

TRE may complement usual care and reduce body weight and fasting blood glucose. Rigorous randomized controlled trials with long-term assessments in a wide range of populations are warranted.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022325657.

Impact of Intermittent Fasting on the Gut Microbiota: A Systematic Review

Obesity often results in severe negative health consequences and represents a growing issue for global health. Reducing food intake is a crucial factor for weight loss. Intermittent fasting is a relatively new intervention that contributes to weight reduction. Considering the intimate relationship between obesity and inflammatory pathologies with gut microbiota alterations, a systematic review of the literature was herein conducted to elucidate the relationship between time-restricted food intake and gut microbiota diversity in humans. Searches are carried out in three databases (PubMed, MedLine/OVID, and Academic Search Complete) between April 2019 and April 2022. Nine studies (all with longitudinal design) were identified as eligible by presenting data about the impact of intermittent fasting schemes on gut microbiota. At the phylum level, Firmicutes and Bacteroidetes increase throughout follow-ups, while 16 bacteria genera change their abundance in response to intermittent fasting. Finally, some genera associated with clinical predictors such as weight change, abdominal circumference, and metabolic variables were reported. Changes induced by fasting schemes positively impact the diversity and abundance of gut microbiota and the biomarkers described here. However, the changes previously reported have been studied in short periods and some return to their basal state after fasting intervention.

The Potential of Fasting-Mimicking Diet as a Preventive and Curative Strategy for Alzheimer's Disease

This review examines the potential of fasting-mimicking diets (FMDs) in preventing and treating Alzheimer's disease (AD). FMDs are low-calorie diets that mimic the physiological and metabolic effects of fasting, including the activation of cellular stress response pathways and autophagy. Recent studies have shown that FMDs can reduce amyloid-beta accumulation, tau phosphorylation, and inflammation, as well as improve cognitive function in animal models of AD. Human studies have also reported improvements in AD biomarkers, cognitive functions, and subjective well-being measures following FMDs. However, the optimal duration and frequency of FMDs and their long-term safety and efficacy remain to be determined. Despite these uncertainties, FMDs hold promise as a non-pharmacological approach to AD prevention and treatment, and further research in this area is warranted.

Time-Restricted Eating Without Calorie Counting for Weight Loss in a Racially Diverse Population : A Randomized Controlled Trial

BACKGROUND

Time-restricted eating (TRE), without calorie counting, has become a popular weight loss strategy, yet long-term randomized trials evaluating its efficacy are limited.

OBJECTIVE

To determine whether TRE is more effective for weight control and cardiometabolic risk reduction compared with calorie restriction (CR) or control.

DESIGN

12-month randomized controlled trial. (ClinicalTrials.gov: NCT04692532).

SETTING

University of Illinois Chicago from January 2021 to September 2022.

PARTICIPANTS

90 adults with obesity.

INTERVENTION

8-hour TRE (eating between noon and 8:00 p.m. only, without calorie counting), CR (25% energy restriction daily), or control (eating over a period of 10 or more hours per day). Participants were not blinded.

MEASUREMENTS

Change in body weight, metabolic markers, and energy intake by month 12.

RESULTS

Seventy-seven persons completed the study. Mean age was 40 years (SD, 11), 33% were Black, and 46% were Hispanic. Mean reduction in energy intake was -425 kcal/d (SD, 531) for TRE and -405 kcal/d (SD, 712) for CR. Compared with the control group, weight loss by month 12 was -4.61 kg (95% CI, -7.37 to -1.85 kg; P ≤ 0.01) (-4.87% [CI, -7.61% to -2.13%]) for the TRE group and -5.42 kg (CI, -9.13 to -1.71 kg; P ≤ 0.01) (-5.30% [CI, -9.06% to -1.54%]) for the CR group, with no statistically significant difference between TRE and CR (0.81 kg [CI, -3.07 to 4.69 kg; P = 0.68]) (0.43% [CI, -3.48% to 4.34%]).

LIMITATION

Not blinded, not powered to detect relatively large differences in weight loss, and lack of adjustment for multiple comparisons.

CONCLUSION

Time-restricted eating is more effective in producing weight loss when compared with control but not more effective than CR in a racially diverse population.

PRIMARY FUNDING SOURCE

National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases.

The Effect of Early Time-Restricted Eating vs Later Time-Restricted Eating on Weight Loss and Metabolic Health

CONTEXT

It remains controversial whether the choice of the daily eating window early or later in time-restricted eating (TRE) intervention (early or later TRE) has different effects on weight loss and metabolic health.

OBJECTIVE

A network meta-analysis was performed to evaluate the efficacy between early and later TRE in adults with obesity or overweight.

METHODS

We searched PubMed, Embase, Web of Science, and Cochrane Library for randomized controlled trials (RCTs) published until October 16, 2022. We conducted a network meta-analysis to evaluate the efficacy of early and later TRE on body weight and metabolic parameters, including glycemic metabolism, blood pressure, and lipid profiles.

RESULTS

Twelve RCTs with 730 obese or overweight adults were included in this meta-analysis. Early TRE and later TRE both elicited moderate reductions in body weight and insulin resistance (IR) (homeostasis model assessment of IR) when compared to non-TRE. Interestingly, early TRE showed more effectiveness than later TRE in improving IR (early vs later TRE: -0.44; 95% CI, -0.86 to -0.02; P < .05), whereas no statistically significant difference was detected in weight loss (early vs later TRE: -0.31 kg; 95% CI, -1.15 to 0.53 kg; P >.05). In addition, early TRE rather than later TRE showed significant benefits in glycemic metabolism and blood pressure when compared to non-TRE. No significant differences between early and later TRE were observed for fasting blood glucose, blood pressure, and lipid profiles.

CONCLUSION

This meta-analysis suggests that people may choose early TRE for more effective weight management and metabolic benefits. Nevertheless, further large-scale RCTs are warranted to verify our findings.

CCE and EODF as two distinct non-shivering thermogenesis models inducing weight loss

Increasing energy expenditure and reducing energy intake are considered two classical methods to induce weight loss. Weight loss through physical methods instead of drugs has been a popular research topic nowadays, but how these methods function in adipose and cause weight loss in body remains unclear. In this study, we set up chronic cold exposure (CCE) and every-other-day fasting (EODF) as two distinct models in long-term treatment to induce weight loss, recording their own characteristics in changes of body temperature and metabolism. We investigated the different types of non-shivering thermogenesis induced by CCE and EODF in white and brown adipose tissue through sympathetic nervous system (SNS), creatine-driven pathway, and fibroblast growth factor 21 (FGF21)-adiponectin axis. CCE and EODF could reduce body weight, lipid composition, increase insulin sensitivity, promote the browning of white fat, and increase the expression of endogenous FGF21 in adipose tissue. CCE stimulated the SNS and increased the thermogenic function of brown fat, and EODF increased the activity of protein kinase in white fat. In this study, we further explained the thermogenic mechanism function in adipose and metabolic benefits of the stable phenotype through physical treatments used for weight loss, providing more details for the literature on weight loss models. The influence on metabolism, non-shivering thermogenesis, endogenous FGF21, and ADPN changes in the long-term treatment of distinct methods (increasing energy expenditure and decreasing energy intake) to induce weight loss.

Endothelial Glycocalyx Preservation-Impact of Nutrition and Lifestyle

The endothelial glycocalyx (eGC) is a dynamic hair-like layer expressed on the apical surface of endothelial cells throughout the vascular system. This layer serves as an endothelial cell gatekeeper by controlling the permeability and adhesion properties of endothelial cells, as well as by controlling vascular resistance through the mediation of vasodilation. Pathogenic destruction of the eGC could be linked to impaired vascular function, as well as several acute and chronic cardiovascular conditions. Defining the precise functions and mechanisms of the eGC is perhaps the limiting factor of the missing link in finding novel treatments for lifestyle-related diseases such as atherosclerosis, type 2 diabetes, hypertension, and metabolic syndrome. However, the relationship between diet, lifestyle, and the preservation of the eGC is an unexplored territory. This article provides an overview of the eGC's importance for health and disease and describes perspectives of nutritional therapy for the prevention of the eGC's pathogenic destruction. It is concluded that vitamin D and omega-3 fatty acid supplementation, as well as healthy dietary patterns such as the Mediterranean diet and the time management of eating, might show promise for preserving eGC health and, thus, the health of the cardiovascular system.

Intermittent protein restriction improves glucose homeostasis in Zucker diabetic fatty rats and single-cell sequencing reveals distinct changes in β cells

Diabetes is caused by the interplay between genetic and environmental factors, therefore changes of lifestyle and dietary patterns are the most common practices for diabetes intervention. Protein restriction and caloric restriction have been shown to improve diabetic hyperglycemia in both animal models and humans. We report here the effectiveness of intermittent protein restriction (IPR) for the intervention of diabetes in Zucker diabetic fatty (ZDF) rats. Administration of IPR significantly reduced hyperglycemia and decreased glucose production in the liver. IPR protected pancreatic islets from diabetes-mediated damages as well as elevated the number and the proliferation activity of β cells. Single-cell RNA sequencing performed with isolated islets from the ZDF rats revealed that IPR was able to reverse the diabetes-associated β cell dedifferentiation. In addition, diabetic β cells in ZDF rats were associated with increased expressions of islet amyloid polypeptide, chromogranin and genes involved in endoplasmic reticulum stress. A β cell dedifferentiation marker Cd81 was also increased in the β cells of diabetic rats. In contrast, the expressions of D-box binding PAR bZIP transcription factor Dbp and immediate-early response genes were reduced in the diabetic β cells. In conclusion, these results indicated that IPR is effective in glycemic control and β cell protection in a diabetic rat model. In addition, diabetes in ZDF rats is associated with changes in the expression of genes involved in many facets of β cell functions.

Research progress of gut microbiota and obesity caused by high-fat diet

Obesity, a chronic metabolic disorder caused by an energy imbalance, has been increasingly prevalent and poses a global health concern. The multifactorial etiology of obesity includes genetics factors, high-fat diet, gut microbiota, and other factors. Among these factors, the implication of gut microbiota in the pathogenesis of obesity has been prominently acknowledged. This study endeavors to investigate the potential contribution of gut microbiota to the development of high-fat diet induced obesity, as well as the current state of probiotic intervention therapy research, in order to provide novel insights for the prevention and management of obesity.

Fasting: From Physiology to Pathology

Overnutrition is a risk factor for various human diseases, including neurodegenerative diseases, metabolic disorders, and cancers. Therefore, targeting overnutrition represents a simple but attractive strategy for the treatment of these increasing public health threats. Fasting as a dietary intervention for combating overnutrition has been extensively studied. Fasting has been practiced for millennia, but only recently have its roles in the molecular clock, gut microbiome, and tissue homeostasis and function emerged. Fasting can slow aging in most species and protect against various human diseases, including neurodegenerative diseases, metabolic disorders, and cancers. These centuried and unfading adventures and explorations suggest that fasting has the potential to delay aging and help prevent and treat diseases while minimizing side effects caused by chronic dietary interventions. In this review, recent animal and human studies concerning the role and underlying mechanism of fasting in physiology and pathology are summarized, the therapeutic potential of fasting is highlighted, and the combination of pharmacological intervention and fasting is discussed as a new treatment regimen for human diseases.

When should I eat: A circadian view on food intake and metabolic regulation

The circadian clock is a hierarchical timing system regulating most physiological and behavioral functions with a period of approximately 24 h in humans and other mammalian species. The circadian clock drives daily eating rhythms that, in turn, reinforce the circadian clock network itself to anticipate and orchestrate metabolic responses to food intake. Eating is tightly interconnected with the circadian clock and recent evidence shows that the timing of meals is crucial for the control of appetite and metabolic regulation. Obesity results from combined long-term dysregulation in food intake (homeostatic and hedonic circuits), energy expenditure, and energy storage. Increasing evidence supports that the loss of synchrony of daily rhythms significantly impairs metabolic homeostasis and is associated with obesity. This review presents an overview of mechanisms regulating food intake (homeostatic/hedonic) and focuses on the crucial role of the circadian clock on the metabolic response to eating, thus providing a fundamental research axis to maintain a healthy eating behavior.

The effects of three weight management methods on body composition and serum lipids of overweight and obese people

Introduction

Obesity has become a major health problem worldwide. Diet management is an important means of weight loss. The aim of this study was to explore the improvement effect of a calorie-restricted diet (CRD), 5 + 2 intermittent fasting (5 + 2 IF), and high protein diet (HPD) on weight composition and serum lipid level of overweight and obese people in a short period (3 months).

Methods

Fifty-three participants aged 18-60 years and with body mass index (BMI) ranging from 24 to 35 kg/m² were screened for inclusion and exclusion criteria and were randomly divided into three groups, i.e., CRD, 5 + 2 IF, and HPD. Basic information, body composition, and venous blood samples were collected at baseline and after 3 months of intervention. Body composition was measured using a body composition analyzer (SK-V9), and serum lipids were assayed using the Roche Cobas e702 automatic biochemistry analysis system. The generalized estimating equation (GEE) was used to analyze and compare the repeated measurements of body composition and levels of serum lipids.

Results

The results showed that total weight, BMI, body fat mass, muscle mass, visceral fat index, and waist and hip circumferences had significantly decreased in all three groups after 3 months of intervention, and the average weight loss was 3.3 ± 1.14, 4.12 ± 0.05, and 2.62 ± 0.13 kg in CRD, 5 + 2 IF, and HPD groups, respectively. The results of the GEE model indicated that compared with the CRD group, the 5 + 2 IF group showed a more significant decrease in weight (β = -0.272, P < 0.001), BMI (β = -0.091, P < 0.001), body fat mass (β = -0.172, P < 0.001), muscle (β = -0.043, P < 0.001), and visceral fat index (β = -0.019, P < 0.001), however, HPD has more advantages in visceral fat index loss (β = -0.011, P < 0.001) and lean body mass preserve (β = 0.229, P < 0.001).

Conclusion

Our findings showed that the 5 + 2 IF may be more effective in reducing total weight and body fat, and HPD may be more helpful in preventing lean body mass loss during a short-term weight loss intervention.

Compliance of participants undergoing a '5-2' intermittent fasting diet and impact on body weight

BACKGROUND

Intermittent fasting (IF) has grown in popularity as a weight loss tool, where caloric intake is fully/partially restricted on a recurring basis. This study aimed to assess compliance with IF fast-day calorie restriction and whether 5-2 IF leads to reduced overall energy intake, weight loss and compensatory increased energy intake on non-fast days.

METHOD

Participants completed diet diaries at baseline and 28 days post 5-2 IF in a repeated measures within-subjects design. 5-2 IF required restricted energy intake to 500 kcal/day (women), 650 kcal/day (men) on two 'fast' days/week whilst eating ad-libitum on other days.

RESULTS

52 participants were included (n = 42 female; age 44 ± 11.2yrs). Median weight loss after 28 days 5-2 IF was statistically significant (1.8 [-2 - 7.3 IQR = 2.2]kg; 2.8 [-2.7-11.2 IQR = 2.5]% p < 0.001). There was a significant reduction in total energy intake during 5-2 IF compared with pre-diet (median 1288.0 [IQR 423.8]kcal and median 1751.5 [IQR 505.3]kcal respectively, p < 0.001). Carbohydrate, protein and fat consumption proportionately reduced during 5-2 IF. Participants had significantly higher energy intake (p < 0.001) on non-fast days that followed a fast day (1928.4 ± 711.9 kcal) compared to non-fast days not following a fast day (1316.2 ± 310.0 kcal). 55.8% complied with fast day calorie restrictions.

CONCLUSION

5-2 IF was associated with significantly reduced energy intake, and weight loss over a 28-day period. Compliance rate was lower than most previous studies. Participants had significantly higher energy intake on non-fast days following fast days suggesting fasting may lead to over-compensation. Further research should investigate strategies to improve compliance and long-term sustainability of IF diets.

Integration of Time-Based Recommendations with Current Pediatric Health Behavior Guidelines: Implications for Obesity Prevention and Treatment in Youth

PURPOSE OF REVIEW

Youth-onset obesity is associated with negative health outcomes across the lifespan including cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, dyslipidemias, asthma, and several cancers. Pediatric health guidelines have traditionally focused on the quality and quantity of dietary intake, physical activity, and sleep.

RECENT FINDINGS

Emerging evidence suggests that the timing (time of day when behavior occurs) and composition (proportion of time spent allocated to behavior) of food intake, movement (i.e., physical activity, sedentary time), and sleep may independently predict health trajectories and disease risks. Several theoretically driven interventions and conceptual frameworks feature behavior timing and composition (e.g., 24 h movement continuum, circadian science and chronobiology, intermittent fasting regimens, structured day hypothesis). These literatures are, however, disparate, with little crosstalk across disciplines. In this review, we examine dietary, sleep, and movement guidelines and recommendations for youths ages 0-18 in the context of theoretical models and empirical findings in support of time-based approaches. The review aims to inform a unifying framework of health behaviors and guide future research on the integration of time-based recommendations into current quantity and quality-based health guidelines for children and adolescents.

Intermittent fasting and time-restricted eating role in dietary interventions and precision nutrition

Intermittent fasting (IF), time-restricted eating (TRE) and fasting-mimicking diets (FMD) are gaining popularity as weight loss programs. As such, the timing and frequency of meals have been recognized as essential contributors to improving cardiometabolic health and a role as adjuvant therapy in cancer. Randomized controlled trials suggested that the weight loss associated with IF is due to a reduced energy intake due to time restriction. Although the supervised TRE clinical trials documented the dietary caloric intake, many free-living studies focused on the timing of meals without a complete characterization of the dietary intake, caloric density, or macronutrient composition. It is possible that both caloric-restriction diets and time-restriction protocols could work synergistically or additively to improve metabolic health outcomes. Like personalized medicine, achieving precision nutrition mandates the provision of the right nutrients to the right patient at the right time. To accomplish this goal, future studies need to evaluate the benefits of IF and TRE. Randomized controlled trials were conducted in different populations, ethnic groups, ages, geographic distribution, physical activity levels, body composition and in patients with obesity, diabetes, and cardiovascular diseases. Also, it is crucial to analyze the dietary composition and caloric density as related to circadian rhythm and timing of meals. It is conceivable that IF and TRE may contribute to precision nutrition strategies to achieve optimal health. However, more research is needed to evaluate IF and TRE effects on health outcomes and any side effects.

A Randomized Controlled Trial of Fasting and Lifestyle Modification in Patients with Metabolic Syndrome: Effects on Patient-Reported Outcomes

Lifestyle interventions can have a positive impact on quality of life and psychological parameters in patients with metabolic syndrome (MetS). In this randomized controlled trial, 145 participants with MetS (62.8% women; 59.7 ± 9.3 years) were randomized to (1) 5-day fasting followed by 10 weeks of lifestyle modification (F + LM; modified DASH diet, exercise, mindfulness; n = 73) or (2) 10 weeks of lifestyle modification only (LM; n = 72). Outcomes were assessed at weeks 0, 1, 12, and 24, and included quality of life (Short-Form 36 Health Survey Questionnaire, SF-36), anxiety/depression (Hospital Anxiety and Depression Scale, HADS), stress (Cohen Perceived Stress Scale, CPSS), mood (Profile of Mood States, POMS), self-efficacy (General Self-Efficacy Scale, GSE), mindfulness (Mindfulness Attention Awareness Scale, MAAS), and self-compassion (Self-Compassion Scale, SCS). At week 1, POMS depression and fatigue scores were significantly lower in F + LM compared to LM. At week 12, most self-report outcomes improved in both groups-only POMS vigor was significantly higher in F + LM than in LM. Most of the beneficial effects within the groups persisted at week 24. Fasting can induce mood-modulating effects in the short term. LM induced several positive effects on quality of life and psychological parameters in patients with MetS.

Insulin-Lowering Diets in Metastatic Cancer

Hyperinsulinemia is an independent risk factor for cancer mortality. Insulin-lowering dietary strategies such as calorie restriction (CR), low-carbohydrate or ketogenic diets (KD), and intermittent fasting (IF) are aimed at reducing systemic stores of nutrients utilized by cancer cells, attenuating insulin-related growth signaling, and improving obesity-related metabolic parameters. In this narrative review, we searched the published literature for studies that tested various insulin-lowering diets in metastatic cancer in preclinical and clinical settings. A total of 23 studies were identified. Of these, 14 were preclinical studies of dietary strategies that demonstrated improvements in insulin levels, inhibition of metastasis, and/or reduction in metastatic disease burden in animal models. The remaining nine clinical studies tested carbohydrate restriction, KD, or IF strategies which appear to be safe and feasible in patients with metastatic cancer. These approaches have also been shown to improve serum insulin and other metabolic parameters. Though promising, the anti-cancer efficacy of these interventions, such as impact on tumor response, disease-specific-, and overall survival, have not yet been conclusively demonstrated. Studies that are adequately powered to evaluate whether insulin-lowering diets improve cancer outcomes are warranted.

Effects of Fasting and Lifestyle Modification in Patients with Metabolic Syndrome: A Randomized Controlled Trial

BACKGROUND

Lifestyle interventions, such as fasting, diet, and exercise, are increasingly used as a treatment option for patients with metabolic syndrome (MS). This study assesses the efficacy and safety of fasting followed by lifestyle modification in patients with MS compared to lifestyle modification only.

METHODS

Single-blind, multicenter, parallel, randomized controlled trial in two German tertiary referral hospitals in metropolitan areas.

INTERVENTIONS

(a) 5-day fasting followed by 10 weeks of lifestyle modification (modified DASH diet, exercise, mindfulness; n = 73); (b) 10 weeks of lifestyle modification only (n = 72).

MAIN OUTCOMES AND MEASURES

Co-primary outcomes were ambulatory systolic blood pressure and the homeostasis model assessment (HOMA) index at week 12. Further outcomes included anthropometric, laboratory parameters, and the PROCAM score at weeks 1, 12, and 24.

RESULTS

A total of 145 patients with metabolic syndrome (62.8% women; 59.7 ± 9.3 years) were included. No significant group differences occurred for the co-primary outcomes at week 12. However, compared to lifestyle modification only, fasting significantly reduced HOMA index (Δ = -0.8; 95% confidence interval [CI] = -1.7, -0.1), diastolic blood pressure (Δ = -4.8; 95% CI = -5.5, -4.1), BMI (Δ = -1.7; 95% CI = -2.0, -1.4), weight (Δ = -1.7; 95% CI = -2.0, -1.4), waist circumference (Δ = -2.6; 95% CI = -5.0, -0.2), glucose (Δ = -10.3; 95% CI = -19.0, -1.6), insulin (Δ = -2.9; 95% CI = -5.3, -0.4), HbA1c (Δ = -0.2; 95% CI = -0.4, -0.05;), triglycerides (Δ = -48.9; 95% CI = -81.0, -16.9), IL-6 (Δ = -1.2; 95% CI = -2.5, -0.005), and the 10-year risk of acute coronary events (Δ = -4.9; 95% CI = -9.5, -0.4) after week 1. Fasting increased uric acid levels (Δ = 1.0; 95% CI = 0.1, 1.9) and slightly reduced eGRF (Δ = -11.9; 95% CI = -21.8, -2.0). Group differences at week 24 were found for weight (Δ = -2, 7; 95% CI = -4.8, -0.5), BMI (Δ = -1.0; 95% CI = -1.8, -0.3), glucose (Δ = -7.7; 95% CI = -13.5, -1.8), HDL (Δ = 5.1; 95% CI = 1.5, 8.8), and CRP (Δ = 0.2; 95% CI = 0.03, 0.4). No serious adverse events occurred.

CONCLUSIONS

A beneficial effect at week 24 was found on weight; fasting also induced various positive short-term effects in patients with MS. Fasting can thus be considered a treatment for initializing lifestyle modification for this patient group; however, it remains to be investigated whether and how the multilayered effects of fasting can be maintained in the medium and longer term.

Obesity-Related Chronic Kidney Disease: Principal Mechanisms and New Approaches in Nutritional Management

Obesity is the epidemic of our era and its incidence is supposed to increase by more than 30% by 2030. It is commonly defined as a chronic and metabolic disease with an excessive accumulation of body fat in relation to fat-free mass, both in terms of quantity and distribution at specific points on the body. The effects of obesity have an important impact on different clinical areas, particularly endocrinology, cardiology, and nephrology. Indeed, increased rates of obesity have been associated with increased risk of cardiovascular disease (CVD), cancer, type 2 diabetes (T2D), dyslipidemia, hypertension, renal diseases, and neurocognitive impairment. Obesity-related chronic kidney disease (CKD) has been ascribed to intrarenal fat accumulation along the proximal tubule, glomeruli, renal sinus, and around the kidney capsule, and to hemodynamic changes with hyperfiltration, albuminuria, and impaired glomerular filtration rate. In addition, hypertension, dyslipidemia, and diabetes, which arise as a consequence of overweight, contribute to amplifying renal dysfunction in both the native and transplanted kidney. Overall, several mechanisms are closely related to the onset and progression of CKD in the general population, including changes in renal hemodynamics, neurohumoral pathways, renal adiposity, local and systemic inflammation, dysbiosis of microbiota, insulin resistance, and fibrotic process. Unfortunately, there are no clinical practice guidelines for the management of patients with obesity-related CKD. Therefore, dietary management is based on the clinical practice guidelines for the nutritional care of adults with CKD, developed and published by the National Kidney Foundation, Kidney Disease Outcome Quality Initiative and common recommendations for the healthy population. Optimal nutritional management of these patients should follow the guidelines of the Mediterranean diet, which is known to be associated with a lower incidence of CVD and beneficial effects on chronic diseases such as diabetes, obesity, and cognitive health. Mediterranean-style diets are often unsuccessful in promoting efficient weight loss, especially in patients with altered glucose metabolism. For this purpose, this review also discusses the use of non-classical weight loss approaches in CKD, including intermittent fasting and ketogenic diet to contrast the onset and progression of obesity-related CKD.

The Fasting and Shifted Timing (FAST) of Eating Study: A pilot feasibility randomized crossover intervention assessing the acceptability of three different fasting diet approaches

BACKGROUND AND AIMS

The aim of this study is to assess the acceptability of following three different fasting protocols [Early Time-restricted Feeding (eTRF; eating majority of kcals before 5pm), Time-restricted Feeding (TRF; restricting feeding window to 8 h/d), or Alternate Day Fasting (ADF; complete fasting every other day)].

METHODS

In this remotely delivered six-week crossover intervention, participants were randomly assigned to follow either an eTRF, TRF, or ADF diet for one week, followed by a one-week washout period. Participants followed all three diets and completed questionnaires assessing self-reported weight, energy intake, dietary acceptability (Food Acceptability Questionnaire), and facilitators and barriers to adhering to each diet. Differences in main outcomes (e.g., dietary acceptability and weight loss) were assessed via repeated measures ANOVA.

RESULTS

A total of 32 of participants began the study (mean BMI of 32.6 ± 6.0 kg/m²). There were no differences in kcals or weight loss among the three diets. Dietary acceptability was higher on the TRF diet (54.1 ± 8.2) than the eTRF (50.2 ± 6.6, p = 0.02) or ADF (48.0 ± 7.9, p = 0.004) diets. The majority of participants (71%) indicated the TRF diet was the easiest to follow and 75% said that ADF was the most difficult. Participants cited having a mobile app to track their diet and being provided with menu plans would help facilitate adherence with their diets.

CONCLUSIONS

This study found that acceptability was highest for an TRF diet and lowest for ADF, with no differences in weight loss or change in energy intake among the TRF, ADF, or eTRF groups.

CLINICAL TRIALS

GOV IDENTIFIER

NCT04527952.