Modified alternate-day fasting vs. calorie restriction in the treatment of patients with metabolic syndrome: A randomized clinical trial

Effects of Intermittent Fasting on Female Reproductive Function: A Review of Animal and Human Studies

PURPOSE OF REVIEW

Intermittent fasting has gained significant attention, yet a comprehensive understanding of its impact on female reproductive health is lacking. This review aims to fill this gap by examining various intermittent fasting regimens and their effects on female reproductive function, along with potential mechanisms.

RECENT FINDINGS

In healthy non-overweight/obese or pregnant animal models, alternate-day fasting (ADF) and an 8-h time-restricted feeding (TRF) window may have adverse effects on reproductive function. However, these regimens show potential to mitigate negative consequences induced by a high-fat diet (HFD) or environmental exposure. A 10-h TRF demonstrates benefits in improving fertility in both normal-weight and HFD-fed animal models. In women with overweight/obesity or polycystic ovary syndrome (PCOS), the 5:2 diet and TRF significantly reduce the free androgen index while elevating sex hormone binding globulin, promising improvements in menstrual regulation. For pregnant Muslim women, available data do not strongly indicate adverse effects of Ramadan fasting on preterm delivery, but potential downsides to maternal weight gain, neonatal birthweight, and long-term offspring health need consideration. Factors linking intermittent fasting to female reproductive health include the circadian clock, gut microbiota, metabolic regulators, and modifiable lifestyles. Drawing definitive conclusions remains challenging in this evolving area. Nonetheless, our findings underscore the potential utility of intermittent fasting regimens as a therapeutic approach for addressing menstruation irregularities and infertility in women with obesity and PCOS. On the other hand, pregnant women should remain cognizant of potential risks associated with intermittent fasting practices.

Habitual food consumption, eating behavior and meal-timing among Jordanian adults with elevated Blood pressure: a cross-sectional population-based study

BACKGROUND

The prevalence of elevated blood pressure (BP) has been raised worldwide. Food consumption, eating habits, and nutritional lifestyle related to meal timing, skipping meals, and meal contents have recently received more attention in studies on BP and metabolic syndrome. Purpose: This study evaluated the association between habitual food consumption, eating behavior, and meal timing with BP among Jordanian adults.

METHODS

A cross-sectional study included 771 Jordanian adults. A food frequency questionnaire was completed. Data about eating habits, meal timing, and emotional eating were collected. BP was measured.

RESULTS

The prevalence of less than recommended intake of vegetables, milk, protein, and fruits was higher in participants with elevated BP (69.2%, 90.2%, 58.9%, and 25.5%, respectively) as compared to the normal BP group (p < 0.001). Consuming vegetables and milk less than the recommended was reported to significantly increase the likelihood of elevated BP by OR= (1.60, and 2.75 (95%CI: 1.06-2.40; 1.62-4.66). Hence, consuming more than recommended fruit reduced the risk of elevated BP by OR = 0.56 (95%CI: 0.38-0.82). A 63.2% of elevated BP participants have three meals daily, a higher percentage of intake of one (23.5%) and two (45.7%) snacks. However, they had a higher percentage of morning eaters (50.7%), had lunch between 1:00-6:00 PM (92.7%), and had dinner between 6:00 and 9:00 PM (68.1%).

CONCLUSIONS

Although Jordanian adults with elevated BP appear to have healthy eating habits and meal timing and frequency, their habitual food consumption falls short of the daily recommendations for milk, fruits, vegetables, and protein.

A detective story of intermittent fasting effect on immunity

Intermittent fasting (IF) refers to periodic fasting routines, that caloric intake is minimized not by meal portion size reduction but by intermittently eliminating ingestion of one or several consecutive meals. IF can instigate comprehensive and multifaceted alterations in energy metabolism, these metabolic channels may aboundingly function as primordial mechanisms that interface with the immune system, instigating intricate immune transformations. This review delivers a comprehensive understanding of IF, paying particular attention to its influence on the immune system, thus seeking to bridge these two research domains. We explore how IF effects lipid metabolism, hormonal levels, circadian rhythm, autophagy, oxidative stress, gut microbiota, and intestinal barrier integrity, and conjecture about the mechanisms orchestrating the intersect between these factors and the immune system. Moreover, the review includes research findings on the implications of IF on the immune system and patients burdened with autoimmune diseases.

Comparing caloric restriction regimens for effective weight management in adults: a systematic review and network meta-analysis

BACKGROUND

Randomized controlled trials have confirmed the effectiveness of four prevalent caloric restriction regimens in reducing obesity-related health risks. However, there is no consensus on the optimal regimen for weight management in adults.

METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane CENTRAL up to January 15, 2024, for randomized controlled trials (RCT) involving adults, evaluating the weight-loss effects of alternate day fasting (ADF), short-term fasting (STF), time-restricted eating (TRE), and continuous energy restriction (CER). The primary outcome was body weight, with secondary outcomes including BMI, fat mass, lean mass, waist circumference, fasting glucose, HOMA-IR, and adverse events. Bayesian network meta-analysis was conducted, ranking regimens using the surface under the cumulative ranking curve and the probability of being the best. Study quality was assessed using the Confidence in Network Meta-Analysis tool.

RESULTS

Data from 47 RCTs (representing 3363 participants) were included. ADF showed the most significant body weight loss (Mean difference (MD): -3.42; 95% Confidence interval (CI): -4.28 to -2.55), followed by TRE (MD: -2.25; 95% CI: -2.92 to -1.59). STF (MD: -1.87; 95% CI: -3.32 to -0.56) and CER (MD: -1.59; 95% CI: -2.42 to -0.79) rank third and fourth, respectively. STF lead to decline in lean mass (MD: -1.26; 95% CI: -2.16, -0.47). TRE showed benefits on fasting glucose (MD: -2.98; 95% CI: -4.7, -1.26). Subgroup analysis revealed all four caloric restriction regimens likely lead to modest weight loss after 1-3 months, with ADF ranked highest, but by 4-6 months, varying degrees of weight regain occur, particularly with CER, while interventions lasting 7-12 months may result in effective weight loss, with TRE potentially ranking first during both the 4-6 months and 7-12 months periods. ADF showing fewer and shorter-lasting physical symptoms.

CONCLUSION

All four included regiments were effective in reducing body weight, with ADF likely having the most significant impact. Each regimen likely leads to modest weight loss after 1-3 months, followed by weight regain by 4-6 months. However, interventions lasting 7-12 months achieve greater weight loss overall.

TRIAL REGISTRATION

PROSPERO: CRD42022382478.

Effects of Different Caloric Restriction Patterns on Blood Pressure and Other Cardiovascular Risk Factors: A Systematic Review and Network Meta-Analysis of Randomized Trials

CONTEXT

All types of caloric restriction are preventive against cardiovascular risk factors, but the best restriction method and most affected factors have not been identified.

OBJECTIVE

The objective of this study was to explore the effects of different caloric restriction methods on various cardiovascular risk factors by horizontally comparing program advantages and disadvantages via network meta-analysis.

DATA SOURCES

The PubMed, Web of Science, Cochrane Library, and Embase literature databases were searched (October 2013 to October 2023).

DATA EXTRACTION

Eligible randomized controlled trials involving participants who underwent caloric restriction and systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and high-density lipoprotein (HDL) cholesterol level measurements were included.

DATA ANALYSIS

Thirty-six of 13 208 records (0.27%) were included. Two researchers reviewed the articles, extracted data, and assessed article quality.

RESULTS

Alternate-day fasting (ADF) reduced SBP (4.88 mmHg; CI, 2.06-7.15) and DBP (5.10 mmHg; CI, 2.44-7.76). Time-restricted eating reduced SBP (2.46 mmHg; CI, 0.16-4.76) but not DBP. Continuous energy restriction (CER) significantly reduced BMI (1.11 kg/m2; CI = 0.16, 2.06) and waist circumference (3.28 cm; CI, 0.62-5.94).

CONCLUSIONS

This meta-analysis confirmed the preventive effect of CER and ADF on various cardiovascular risk factors. Additionally, CER is more likely to reduce obesity, and ADF is more likely to reduce blood pressure (BP). Based on this meta-analysis, CER is recommended to control obesity only for people who are obese and do not have elevated BP or other abnormal indicators. Additionally, ADF for early control or prevention is recommended for patients who have abnormal BP or other cardiovascular risk factors.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023455889.

Effects of Different Exercises Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis

BACKGROUND

Exercise and dietary interventions are essential for maintaining weight and reducing fat accumulation. With the growing popularity of various dietary strategies, evidence suggests that combining exercise with dietary interventions offers greater benefits than either approach alone. Consequently, this combined strategy has become a preferred method for many individuals aiming to maintain health. Calorie restriction, 5/2 intermittent fasting, time-restricted feeding, and the ketogenic diet are among the most popular dietary interventions today. Aerobic exercise, resistance training, and mixed exercise are the most widely practiced forms of physical activity. Exploring the best combinations of these approaches to determine which yields the most effective results is both meaningful and valuable. Despite this trend, a comparative analysis of the effects of different exercise and diet combinations is lacking. This study uses network meta-analysis to evaluate the impact of various combined interventions on body composition and to compare their efficacy.

METHODS

We systematically reviewed literature from database inception through May 2024, searching PubMed, Web of Science, Embase, and the Cochrane Library. The study was registered in PROSPERO under the title: "Effects of Exercise Combined with Different Dietary Interventions on Body Composition: A Systematic Review and Network Meta-Analysis" (identifier: CRD42024542184). Studies were meticulously selected based on specific inclusion and exclusion criteria (The included studies must be randomized controlled trials involving healthy adults aged 18 to 65 years. Articles were rigorously screened according to the specified inclusion and exclusion criteria.), and their risk of bias was assessed using the Cochrane risk of bias tool. Data were aggregated and analyzed using network meta-analysis, with intervention efficacy ranked by Surface Under the Cumulative Ranking (SUCRA) curves.

RESULTS

The network meta-analysis included 78 randomized controlled trials with 5219 participants, comparing the effects of four combined interventions: exercise with calorie restriction (CR+EX), exercise with time-restricted eating (TRF+EX), exercise with 5/2 intermittent fasting (5/2F+EX), and exercise with a ketogenic diet (KD+EX) on body composition. Intervention efficacy ranking was as follows: (1) Weight Reduction: CR+EX > KD+EX > TRF+EX > 5/2F+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.94 (-3.64, 9.52); 2.37 (-0.40, 5.15); 1.80 (-1.75, 5.34)). (2) BMI: CR+EX > KD+EX > 5/2F+EX > TRF+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 1.95 (-0.49, 4.39); 2.20 (1.08, 3.32); 1.23 (-0.26, 2.71)). (3) Body Fat Percentage: CR+EX > 5/2F+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of 5/2F+EX, TRF+EX and KD+EX are 2.66 (-1.56, 6.89); 2.84 (0.56, 5.13); 3.14 (0.52, 5.75).). (4) Lean Body Mass in Male: CR+EX > TRF+EX > KD+EX (Relative to CR+EX, the effect sizes of TRF+EX and KD+EX are -1.60 (-6.98, 3.78); -2.76 (-7.93, 2.40)). (5) Lean Body Mass in Female: TRF+EX > CR+EX > 5/2F+EX > KD+EX (Relative to TRF+EX, the effect sizes of CR+EX, 5/2F+EX and KD+EX are -0.52 (-2.58, 1.55); -1.83 (-4.71, 1.04); -2.46 (-5.69,0.76).).

CONCLUSION

Calorie restriction combined with exercise emerged as the most effective strategy for reducing weight and fat percentage while maintaining lean body mass. For women, combining exercise with time-restricted eating proved optimal for preserving muscle mass. While combining exercise with a ketogenic diet effectively reduces weight, it is comparatively less effective at decreasing fat percentage and preserving lean body mass. Hence, the ketogenic diet combined with exercise is considered suboptimal.

Therapeutic Potential of Various Intermittent Fasting Regimens in Alleviating Type 2 Diabetes Mellitus and Prediabetes: A Narrative Review

Intermittent fasting has drawn significant interest in the clinical research community due to its potential to address metabolic complications such as obesity and type 2 diabetes mellitus. Various intermittent fasting regimens include alternate-day fasting (24 h of fasting followed by 24 h of eating), time-restricted fasting (fasting for 14 h and eating within a 10 h window), and the 5:2 diet (fasting for two days and eating normally for the other five days). Intermittent fasting is associated with a reduced risk of type 2 diabetes mellitus-related complications and can slow their progression. The increasing global prevalence of type 2 diabetes mellitus highlights the importance of early management. Since prediabetes is a precursor to type 2 diabetes mellitus, understanding its progression is essential. However, the long-term effects of intermittent fasting on prediabetes are not yet well understood. Therefore, this review aims to comprehensively compile existing knowledge on the therapeutic effects of intermittent fasting in managing type 2 diabetes mellitus and prediabetes.

Fasting and calorie restriction modulate age-associated immunosenescence and inflammaging

Aging is a multifaceted process impacting cells, tissues, organs, and organ systems of the body. Like other systems, aging affects both the adaptive and the innate components of the immune system, a phenomenon known as immunosenescence. The deregulation of the immune system puts elderly individuals at higher risk of infection, lower response to vaccines, and increased incidence of cancer. In the Western world, overnutrition has increased the incidence of obesity (linked with chronic inflammation) which increases the risk of metabolic syndrome, cardiovascular disease, and cancer. Aging is also associated with inflammaging a sterile chronic inflammation that predisposes individuals to age-associated disease. Genetic manipulation of the nutrient-sensing pathway, fasting, and calorie restriction (CR) has been shown to increase the lifespan of model organisms. As well in humans, fasting and CR have also been shown to improve different health parameters. Yet the direct effect of fasting and CR on the aging immune system needs to be further explored. Identifying the effect of fasting and CR on the immune system and how it modulates different parameters of immunosenescence could be important in designing pharmacological or nutritional interventions that slow or revert immunosenescence and strengthen the immune system of elderly individuals. Furthermore, clinical intervention can also be planned, by incorporating fasting or CR with medication, chemotherapy, and vaccination regimes. This review discusses age-associated changes in the immune system and how these changes are modified by fasting and CR which add information on interventions that promote healthy aging and longevity in the growing aging population.

Risks and Benefits of Intermittent Fasting for the Aging Cardiovascular System

Population aging and the associated increase in cardiovascular disease rates pose serious threats to global public health. Different forms of fasting have become an increasingly attractive strategy to directly address aging and potentially limit or delay the onset of cardiovascular diseases. A growing number of experimental studies and clinical trials indicate that the amount and timing of food intake as well as the daily time window during which food is consumed, are crucial determinants of cardiovascular health. Indeed, intermittent fasting counteracts the molecular hallmarks of cardiovascular aging and promotes different aspects of cardiometabolic health, including blood pressure and glycemic control, as well as body weight reduction. In this report, we summarize current evidence from randomized clinical trials of intermittent fasting on body weight and composition as well as cardiovascular and metabolic risk factors. Moreover, we critically discuss the preventive and therapeutic potential of intermittent fasting, but also possible detrimental effects in the context of cardiovascular aging and related disease. We delve into the physiological mechanisms through which intermittent fasting might improve cardiovascular health, and raise important factors to consider in the design of clinical trials on the efficacy of intermittent fasting to reduce major adverse cardiovascular events among aged individuals at high risk of cardiovascular disease. We conclude that despite growing evidence and interest among the lay and scientific communities in the cardiovascular health-improving effects of intermittent fasting, further research efforts and appropriate caution are warranted before broadly implementing intermittent fasting regimens, especially in elderly persons.

From fasting to fat reshaping: exploring the molecular pathways of intermittent fasting-induced adipose tissue remodeling

Obesity, characterised by excessive fat accumulation, is a complex chronic condition that results from dysfunctional adipose tissue expansion due to prolonged calorie surplus. This leads to rapid adipocyte enlargement that exceeds the support capacity of the surrounding neurovascular network, resulting in increased hypoxia, inflammation, and insulin resistance. Intermittent fasting (IF), a dietary regimen that cycles between periods of fasting and eating, has emerged as an effective strategy to combat obesity and improve metabolic homeostasis by promoting healthy adipose tissue remodeling. However, the precise molecular and cellular mechanisms behind the metabolic improvements and remodeling of white adipose tissue (WAT) driven by IF remain elusive. This review aims to summarise and discuss the relationship between IF and adipose tissue remodeling and explore the potential mechanisms through which IF induces alterations in WAT. This includes several key structural changes, including angiogenesis and sympathetic innervation of WAT. We will also discuss the involvement of key signalling pathways, such as PI3K, SIRT, mTOR, and AMPK, which potentially play a crucial role in IF-mediated metabolic adaptations.

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.

Intermittent Fasting: Myths, Fakes and Truth on This Dietary Regimen Approach

Intermittent fasting (IF) has been indicated as a valuable alternative to the classical caloric restriction dietary regimen for lowering body weight and preventing obesity-related complications, such as metabolic syndrome and type II diabetes. However, is it effective? In this review article, we analyzed over 50 clinical studies in which IF, conducted by alternate day fasting (ADF) or time-restricted feeding (TRF), was compared with the caloric restriction approach. We evaluated the different roles of IF in treating and preventing human disorders such as metabolic syndrome, type II diabetes, and some types of cancer, as well as the usefulness of IF in reducing body weight and cardiovascular risk factors such as hypertension. Furthermore, we explored the cellular pathways targeted by IF to exert their beneficial effects by activating effector proteins that modulate cell functions and resistance to oxidative stress. In contrast, we investigated concerns regarding human health related to the adoption of IF dietary regimens, highlighting the profound debate surrounding weight loss regimens. We examined and compared several clinical trials to formulate an updated concept regarding IF and its therapeutic potential.

The effects of jujube (Ziziphus jujube) on metabolic and mental health outcomes in patients with metabolic syndrome: A randomized controlled trial

OBJECTIVES

The effects of jujube (Ziziphus jujube) consumption on metabolic and mental health outcomes in subjects diagnosed with metabolic syndrome (MetS) is unknown and remains to be examined. Hence, we carried out a parallel-group, randomized controlled trial to investigate this issue.

METHODS

Eligible participants were randomly assigned to the intervention (n = 30) or the control (n = 30) groups to receive either jujube or a placebo for eight weeks. Subjects were provided with 30 g dried jujube powder or placebo and were asked to consume half of the powder at 10 a.m. and the rest at 4 p.m. Lipid profile, fasting blood glucose (FBG), waist circumference (WC), and blood pressure were evaluated as primary outcomes. Secondary outcomes collected were mental health measures (e.g., depression, anxiety, and stress).

RESULTS

Jujube consumption failed to decrease FBG, total cholesterol, low-density lipoprotein cholesterol, and blood pressure, as well as depression and anxiety scores (P > 0.05). However, the between-group comparison revealed a significant improvement in WC (- 3.98 vs. - 0.51, P = 0.01), triglyceride (TG) (- 24.96 vs. - 0.73, P = 0.03), and high-density lipoprotein cholesterol (HDL-C) (2.83 vs. 0.40, P = 0.01) in the jujube group compared to the placebo. In addition, compared to the control group, jujube consumption led to a significant improvement in the score of stress (- 5.80 vs. - 2.86, P = 0.01).

CONCLUSION

Jujube consumption only had beneficial effects on WC, TG, and HDL-C in subjects with MetS. However, the current study has methodological weaknesses in blinding and herb purity/potency testing, which should be addressed in future studies.

Intermittent fasting as a dietary intervention with potential sexually dimorphic health benefits

Intermittent fasting (IF) has proven to be a feasible dietary intervention for the wider population. The recent increase in IF clinical trials highlights its potential effects on health, including changes in body composition, cardiometabolic status, and aging. Although IF may have clinical applications in different populations, studies suggest there may be sex-specific responses in parameters such as body composition or glucose and lipid metabolism. Here, the existing literature on IF clinical trials is summarized, the application of IF in both disease prevention and management is discussed, and potential disparities in response to this type of diet between men and women are assessed. Moreover, the potential mechanisms that may be contributing to the sexually dimorphic response, such as age, body composition, tissue distribution, or sex hormones are investigated. This review underscores the need to further study these sex-specific responses to IF to define the most effective time frames and length of fasting periods for men and women. Tailoring IF to specific populations with a personalized approach may help achieve its full potential as a lifestyle intervention with clinical benefits.

Comparative efficacy of energy-restricted dietary interventions in overweight and obese populations: A systematic review and network meta-analysis

This meta-analysis compared the effectiveness of different energy-restricted diets on body composition, glucose metabolism, and lipid metabolism in overweight and obese populations. Five databases were searched to identify relevant studies in English from inception until July 20, 2023, for randomized controlled trials of at least 2 weeks duration assessing the effects of continuous energy-restricted diets compared with any intermittent energy-restricted diet in obesity adults. The risk of bias was assessed using the Cochrane Risk of Bias Tool version 2.0, while the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) system was used to assess the certainty of the evidence. A non-informative prior distribution Bayesian network meta-analysis was conducted. Thirty-eight studies (3039 participants) assessing four energy-restricted diets were included. Three RCTs were at high risk of bias with a very low to moderate certainty of evidence. Combined with pairwise comparisons and surface under the cumulative ranking curve, alternate-day fasting may be the best energy restriction regimen with the potential to have the most beneficial effects on various aspects of the obesity population. More rigorously designed and long-term follow-up studies are warranted.

The effect of time of eating on cardiometabolic risk in primary and secondary prevention of cardiovascular disease

Continuous energy restriction is currently considered the first-line dietary therapy for weight loss in individuals with obesity. Recently, interventions which alter the eating window and time of eating occasions have been explored as means to achieve weight loss and other cardiometabolic improvements such as a reduction in blood pressure, glycaemia, lipids and inflammation. It is unknown, however, whether these changes result from unintentional energy restriction or from other mechanisms such as the alignment of nutrient intake with the internal circadian clock. Even less is known regarding the safety and efficacy of these interventions in individuals with established chronic noncommunicable disease states, such as cardiovascular disease. This review examines the effects of interventions which alter both eating window and time of eating occasions on weight and other cardiometabolic risk factors in both healthy participants and those with established cardiovascular disease. We then summarise the state of existing knowledge and explore future directions of study.

Does an alternate-day modified fasting diet improve premenstrual syndrome symptoms and health-related quality of life in obese or overweight women with premenstrual syndrome? A randomized, controlled trial

Background

Premenstrual syndrome disorder (PMS) is a condition that affects health-related quality of life (HRQoL) and encompasses a variety of symptoms, including psychological, physical, and behavioral symptoms. Some evidence suggests that an increase in body mass index (BMI) can reduce both HRQoL and menstrual quality. This is because the body fat tissue can affect menstrual cycles by changing the estrogen/progesterone ratio. This study investigated the impact of two diets alternate-day modified fasting (ADMF) and daily calorie restriction (DCR) - on PMS syndrome and HRQoL.

Methods

The study was a randomized controlled, open-label trial that lasted for 8 weeks and involved 60 obese/overweight women. Participants were recruited from the Health Service Centers of Kashan University of Medical Sciences using simple random sampling. The study compared the impact of the ADMF and DCR diets on HRQoL and PMS symptoms. Patients were classified based on their BMI and age and then allocated to either the intervention (ADMF) or control (DCR) group using a random numbers table. The study measured HRQoL, PMS severity, weight, BMI, body fat mass, waist circumference, fat-free mass, and skeletal muscle mass before and after the study. The study had an almost 18% dropout rate.

Results

Significant improvements were observed in mood lability (p = 0.044) and expressed anger (p < 0.001) in relation to PMS symptoms. However, no significant differences were detected in the changes of other COPE subscales. The ADMF diet had a significant impact on the 12-item Short-Form Health Survey (SF-12) total score (p < 0.001) and physical function subscales (p = 0.006) as well as mental health (p < 0.001) when compared to the control diet. This implies that the ADMF diet increased both SF-12 total score and its subscales. The intervention led to improvements in HRQoL, physical function, and mental health. Additionally, significant improvements in BMI and weight were observed between the two groups pre- and post-study (p < 0.001). Anthropometric data, including body fat mass and waist circumference, showed a significant improvement (p < 0.001 and p = 0.029, respectively) before and after the study. However, there were no significant changes in fat-free mass (p = 0.936) and skeletal muscle mass (p = 0.841) between the two groups.

Conclusion

The study suggested that ADMF can improve HRQoL, mood lability, and expressed anger. It also showed that ADMF can reduce waist circumference, weight, and body fat mass in obese/overweight women.

Clinical trial registration

The Iranian Registry of Clinical Trials (IRCT20220522054958N1).

Network meta-analysis of three different forms of intermittent energy restrictions for overweight or obese adults

This network meta-analysis aimed to compare the efficacy of three forms of intermittent energy restriction (IER), including alternate-day fasting (ADF), the 5:2 diet, and time-restricted feeding (TRF), in overweight or obese adults. A literature search was conducted in PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) to find relevant randomized controlled trials (RCTs) until August 10, 2022. The modified Cochrane risk of bias assessment tool was applied to assess the methodological quality of eligible studies. Random network meta-analysis was conducted using STATA 14.0. Sixteen RCTs were included, with 1228 patients. Overall, the methodological quality ranged from low to moderate. ADF was superior to CER and 5:2 diet in reducing waist circumference, whereas 5:2 diet was superior to CER in reducing BMI. Regarding fat mass and drop-out, all forms of IER were comparable. Sensitivity analyses indicated that the type of individuals had no influence on the pooled results; nevertheless, ADF significantly reduced weight compared to CER and achieved significant waist circumference reduction compared to CER, 5:2 diet, and TRF. ADF may be preferentially prescribed for overweight or obese adults. More large-scale and high-quality studies are required, however, to investigate the effect of TRF on overweight and obesity.

Non-invasive omics analysis delineates molecular changes in water-only fasting and its sex-discriminating features in metabolic syndrome patients

Fasting has been grown in popularity with multiple potential benefits. However, very few studies dynamically monitor physiological and pathological changes during long-term fasting using noninvasive methods. In the present study, we recruited 37 individuals with metabolic syndrome to engage in a 5-day water-only fasting regimen, and simultaneously captured the molecular alterations through urinary proteomics and metabolomics. Our findings reveal that water-only fasting significantly mitigated metabolic syndrome-related risk markers, such as body weight, body mass index, abdominal circumference, blood pressure, and fasting blood glucose levels in metabolic syndrome patients. Indicators of liver and renal function remained within the normal range, with the exception of uric acid. Notably, inflammatory response was inhibited during the water-only fasting period, as evidenced by a decrease in the human monocyte differentiation antigen CD14. Intriguingly, glycolysis, tricarboxylic acid cycle, and oxidative phosphorylation underwent a sex-dependent reprogramming throughout the fasting period, whereby males exhibited a greater upregulation of carbohydrate metabolism-related enzymes than females. This disparity may be attributed to evolutionary pressures. Collectively, our study sheds light on the beneficial physiological effects and novel dynamic molecular features associated with fasting in individuals with metabolic syndrome using noninvasive methods.

Stress and human health in diabetes: A report from the 19th Chicago Biomedical Consortium symposium

Stress and diabetes coexist in a vicious cycle. Different types of stress lead to diabetes, while diabetes itself is a major life stressor. This was the focus of the Chicago Biomedical Consortium's 19th annual symposium, "Stress and Human Health: Diabetes," in November 2022. There, researchers primarily from the Chicago area met to explore how different sources of stress - from the cells to the community - impact diabetes outcomes. Presenters discussed the consequences of stress arising from mutant proteins, obesity, sleep disturbances, environmental pollutants, COVID-19, and racial and socioeconomic disparities. This symposium showcased the latest diabetes research and highlighted promising new treatment approaches for mitigating stress in diabetes.

Intermittent fasting and bone health: a bone of contention?

Intermittent fasting (IF) is a promising strategy for weight loss and improving metabolic health, but its effects on bone health are less clear. This review aims to summarise and critically evaluate the preclinical and clinical evidence on IF regimens (the 5:2 diet, alternate-day fasting (ADF) and time-restricted eating (TRE)/time-restricted feeding and bone health outcomes. Animal studies have utilised IF alongside other dietary practices known to elicit detrimental effects on bone health and/or in models mimicking specific conditions; thus, findings from these studies are difficult to apply to humans. While limited in scope, observational studies suggest a link between some IF practices (e.g. breakfast omission) and compromised bone health, although lack of control for confounding factors makes these data difficult to interpret. Interventional studies suggest that TRE regimens practised up to 6 months do not adversely affect bone outcomes and may even slightly protect against bone loss during modest weight loss (< 5 % of baseline body weight). Most studies on ADF have shown no adverse effects on bone outcomes, while no studies on the ‘5–2’ diet have reported bone outcomes. Available interventional studies are limited by their short duration, small and diverse population samples, assessment of total body bone mass exclusively (by dual-energy X-ray absorptiometry) and inadequate control of factors that may affect bone outcomes, making the interpretation of existing data challenging. Further research is required to better characterise bone responses to various IF approaches using well-controlled protocols of sufficient duration, adequately powered to assess changes in bone outcomes and designed to include clinically relevant bone assessments.

Effects of time-restricted eating with different eating windows on human metabolic health: pooled analysis of existing cohorts

BACKGROUND

Time-restricted eating (TRE), a feasible form of intermittent fasting, has been proven to benefit metabolic health in animal models and humans. To our knowledge, specific guidance on the appropriate period for eating during TRE has not yet been promoted. Therefore, to compare and assess the relative effectiveness estimates and rankings of TRE with different eating windows on human metabolic health, we conducted a systematic review and network meta-analysis (NMA).

METHOD

PubMed, EMBASE and the Cochrane Library were searched for randomized controlled trials that compared different eating windows on human metabolic health for adults. A Bayesian NMA was used to compare direct and indirect effects to determine the best different eating windows, and scientific evidence using GRADE.

RESULTS

Twenty-seven RCTs comparing TRE with different eating windows on human metabolic health were reviewed, and all were included in the NMA. Compared with the normal diet group (non-TRE), the TRE group has certain benefits in reducing weight and fasting insulin. In terms of reducing fasting insulin, the 18:6 group (eating time = 6 h) was better than the 14:10 group (eating time = 10 h) and 16:8 group (eating time = 8 h) (P < 0.05); The < 6 group (eating time < 6 h) was better than the 14:10 group (P < 0.05). In terms of reducing fasting glucose, the < 6 group was better than the 14:10 group (P < 0.05). There were no statistical variations in weight, HDL, TG, and LDL across the different modes of TRE (P > 0.05).

CONCLUSIONS

Our research showed that no particular metabolic advantages of various eating windows were found. Therefore, our results suggested that different eating windows could promote similar benefits for metabolic parameters.

Intermittent fasting-the future treatment in NASH patients?

NASH is one of the leading causes of chronic liver disease with the potential of evolving towards end-stage liver disease and HCC, even in the absence of cirrhosis. Apart from becoming an increasingly prevalent indication for liver transplantation in cirrhotic and HCC patients, its burden on the healthcare system is also exerted by the increased number of noncirrhotic NASH patients. Intermittent fasting has recently gained more interest in the scientific community as a possible treatment approach for different components of metabolic syndrome. Basic science and clinical studies have shown that apart from inducing body weight loss, improving cardiometabolic parameters, namely blood pressure, cholesterol, and triglyceride levels; insulin and glucose metabolism; intermittent fasting can reduce inflammatory markers, endoplasmic reticulum stress, oxidative stress, autophagy, and endothelial dysfunction, as well as modulate gut microbiota. This review aims to further explore the main NASH pathogenetic metabolic drivers on which intermittent fasting can act upon and improve the prognosis of the disease, and summarize the current clinical evidence.

Cellular mechanism of diabetes remission by bariatric surgery

Bariatric surgery is a powerful therapy for type 2 diabetes in patients with obesity. The mechanism of insulin sensitization by surgery has been extensively investigated in weight loss-dependent and weight loss-independent conditions. However, a consensus remains to be established regarding the underlying mechanisms. Energy deficit induced by calorie restriction (CR), that occurs both before and after surgery, represents a unique physiological basis for insulin sensitization regardless of weight loss. In support, we integrate evidence in the literature to provide an energy-based view of insulin sensitization as follows: surgery improves insulin sensitivity through the energy deficit induced by CR, leading to correction of mitochondrial overload in multiple cell types; this then triggers functional reprogramming of relevant tissues leading to diabetes remission.

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 effects of Capsicum annuum supplementation on lipid profiles in adults with metabolic syndrome and related disorders: A systematic review and meta-analysis of randomized controlled trials

The electiveness of Capsicum annuum supplementation in controlling dyslipidemia in adults has been unclear. Therefore, this meta-analysis focuses on the relationship between C. annuum supplementation and lipid profile in adults with metabolic syndrome (MetS) and related disorders. PubMed, Scopus, ISI Web of Science, and the Cochrane Library were searched up to March 2021. Only randomized controlled trials (RCTs) studying the administration of C. annuum compared to control on lipid markers in adults with MetS and related disorders were examined. Pooled effect sizes were reported as weighted mean differences (WMDs) and 95% confidence intervals (CIs). The results of four eligible RCTs showed that C. annuum supplementation could significantly reduce total cholesterol (TC) (WMD: -4.98 mg/dL, 95% CI: -7.08 to -2.88, p ≤ 0.001) levels, but did not regulate triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol concentrations. In summary, the present findings suggest the beneficial effects of C. annuum supplementation on the reduction of plasma levels of TC. However, to draw a firm link between C. annuum supplementation and lipid profile, more trials with adequate sample sizes, specifically in subjects with dyslipidemia are warranted.

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.

Effects of time-restricted feeding and walking exercise on the physical health of female college students with hidden obesity: a randomized trial

Purpose

Time-restricted feeding (TRF) is an emerging dietary pattern with many potential effects. This study focused on the effects of TRF and walking on the physical health of female college students with hidden obesity.

Methods

A total of 77 female college students with hidden obesity, aged 18-22 years, were randomly assigned to a control group (CON, N = 19), time-restricted feeding group (TRF, N = 19), exercise group (EXE, N = 20), and TRF combined with exercise group (TRF + EXE, N = 19). The interventions lasted for 8 weeks. Tests assessing body shape, body composition, bone mineral density, blood lipid levels, and blood pressure were performed before and after the intervention.

Results

(1) Intragroup comparison before and after the intervention revealed that the TRF, EXE, and TRF + EXE groups had significantly reduced body weight (p < 0.01), body mass index (BMI) (p < 0.05), and lean tissue mass (LTM) (p < 0.01) but increased total cholesterol (TC) levels (p < 0.05) after the intervention. Body fat percentage (BF%) increased considerably in the EXE and TRF + EXE groups (p < 0.01). (2) Post-intervention comparisons of body weight, BMI, LTM, adipose tissue mass (ATM), total bone mineral density (TBMD), blood lipid levels, and blood pressure between the intervention groups (TRF, EXE, and TRF + EXE) and the CON group showed no significant differences (p > 0.05). (3) A comparison of the changes between the groups before and after the intervention showed significant decreases in body weight in the TRF and TRF + EXE groups (p < 0.05) and in both BMI and LTM in the TRF, EXE, and TRF + EXE groups (p < 0.05) compared to those in the CON group. The BF% change in the EXE and TRF + EXE groups were significantly greater than that in the TRF group (p < 0.01).

Conclusion

TRF effectively decreased body weight and BMI in female college students with hidden obesity. However, increased blood lipid levels and decreased LTM levels were also observed. The effects of TRF combined with exercise were not superior to those of TRF or walking alone in terms of body weight, body mass index, body composition, TBMD, or blood lipid levels. Therefore, TRF cannot be considered the best option for fat reduction in female college students with hidden obesity.

Alternate-day modified fasting diet improves weight loss, subjective sleep quality and daytime dysfunction in women with obesity or overweight: a randomized, controlled trial

Background

Both sleep time and quality can be associated with overweight or obesity. In obese people, visceral fat tissue develops, which results in an increment in the production of cytokines. The increased production of inflammatory cytokines can disturb the sleep/wake cycle. Therefore, weight loss by reducing fat tissue can improve sleep disorders. Intermittent fasting diets are popular and effective diets that can decrease body weight and improve anthropometric data and body composition. The present study aimed to evaluate the effect of Alternate-day Modified Fasting (ADMF) on sleep quality, body weight, and daytime sleepiness.

Methods

Classification of 56 obese or overweight women, based on age and body mass index (BMI), was done using stratified randomization. Then individuals were assigned to the ADMF group (intervention) or Daily Calorie Restriction (CR) group (control) using the random numbers table for 8 weeks. We measured the Pittsburgh sleep quality Index (PSQI), weight, BMI, and the Epworth sleepiness scale (ESS) as primary outcomes and assessed subjective sleep quality (SSQ), sleep latency, sleep disturbances, habitual sleep efficiency, daytime dysfunction, and sleep duration as secondary outcomes at baseline and after the study.

Results

Following an ADMF diet resulted in a greater decrease in weight (kg) [-5.23 (1.73) vs. -3.15 (0.88); P < 0.001] and BMI (kg/m²) [-2.05 (0.66) vs. -1.17 (0.34); P < 0.001] compared to CR. No significant differences were found in the changes of PSQI [-0.39 (1.43) vs. -0.45 (1.88); P = 0.73] and ESS [-0.22 (1.24) vs. -0.54 (1.67); P = 0.43] between two groups. Also, following the ADMF diet led to significant changes in SSQ [-0.69 (0.47) vs. -0.08 (0.40); P = <0.001], and daytime dysfunction [-0.65 (0.57) vs. 0.04 (0.75); P: 0.001] in compare with CR diet.

Conclusion

These results suggested that an ADMF could be a beneficial diet for controlling body weight and BMI. The ADMF diet didn't affect PSQI and ESS in women with overweight or obesity but significantly improved SSQ and daytime dysfunction.

Clinical Trial Registration

The Iranian Registry of Clinical Trials (IRCT20220522054958N3), https://www.irct.ir/trial/64510.

Intermittent energy restriction vs. continuous energy restriction on cardiometabolic risk factors in patients with metabolic syndrome: a meta-analysis and systematic review

Background

This is a systematic review and meta-analysis to compare the efficacy of intermittent energy restriction (IER) vs. continuous energy restriction (CER) on weight loss, body composition, blood pressure, and other cardiometabolic risk factors in patients with metabolic syndrome (MetS) risk factors.

Methods

We searched and screened PubMed, Embase, Cochrane Library, and Web of Science from inception to May 8, 2022 for randomized controlled trials. Two review authors independently selected studies, extracted data, assessed quality and risk of bias and cross-checked extracts to resolve discrepancies when required. We expressed effect size as mean difference (MD) and 95% confidence interval (CI). The major outcome was the improvement of MetS risk factors, including changes in waist circumference (WC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), blood pressure (BP), and fasting plasma glucose (FPG) levels. The secondary outcomes were body weight (BW), body mass index (BMI), body fat (BF), fat free mass (FFM), hip circumference (HC), fasting insulin (FINs), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-c).

Results

The meta-analysis included 16 articles (20 trials) with a total of 1,511 participants. All studies had a low risk of bias for random sequence generation. The IER and CER intervention equally improved MetS risk factors WC (MD = -0.47, 95% CI [-1.19, 0.25]), TG (MD = -0.02 mmol/L, 95% CI [-0.11, 0.07]), FPG (MD = -0.02 mmol/L, 95% CI [-0.10, 0.05]) and BP (systolic blood pressure: MD = 0.93 mmHg, 95% CI [-2.74, 4.61]; diastolic blood pressure: MD =1.15 mmHg, 95% CI [-0.24, 2.55]), but HDL-c (MD = 0.03 mmol/L, 95% CI [0.01, 0.05]) was significant improved in IER when compared with CER. For second outcomes, BW (MD = -0.8 kg, 95% CI [-1.26, -0.33]), BF (MD = -0.75 kg, 95% CI [-1.73, -0.13]) and FFM (MD = -0.49 kg, 95% CI [-0.92, -0.05]) were also significant improved in IER, and not for other outcomes.

Conclusion

Both IER and CER could improve MetS biomarkers, but IER was more effective than CER in the improvement of HDL-c only. For secondary outcomes, IER was also more effective for BW, BF and FFM, but there were no differences in effects for other outcomes.

Effect of modified alternate day fasting diet on the severity of premenstrual syndrome and health-related quality of life in women with overweight or obesity: a trial study protocol

INTRODUCTION

Premenstrual syndrome (PMS) includes a range of physical, behavioural and psychological symptoms and decreases women's health-related quality of life (HRQoL). It has been proposed that increased body mass index (BMI) is associated with menstrual problems and decreased HRQoL. The body fat amount plays a role in menstrual cycles by altering the oestrogen/progesterone ratio. Alternate day fasting as an unusual diet results in the improvement of anthropometric indices and reduction of body weight. This study aims to investigate the effect of a daily calorie restriction diet and a modified alternate day fasting diet on PMS and HRQoL.

METHODS AND ANALYSIS

This 8-week open-label parallel randomised controlled trial examines the impact of a modified alternate-day fasting diet and daily caloric restriction on the severity of PMS and HRQoL in obese or overweight women. Using simple random sampling, women between the ages of 18 years and 50 years and 25 ≤ BMI ˂ 40 who meet the inclusion and exclusion criteria will be chosen from the Kashan University of Medical Sciences Centre. Patients will be randomised, based on BMI and age through stratified randomisation. Then by the random numbers table, they are allocated to fasting (intervention) or daily calorie restriction (control) groups. Outcomes are chosen for the trial: the difference in the severity of PMS, HRQoL, BMI, body fat mass, fat-free mass, waist-to-hip ratio, waist circumference, hip circumference, per cent body fat, skeletal muscle mass and visceral fat area from baseline to 8 weeks.

ETHICS AND DISSEMINATION

The Kashan University of Medical Sciences Ethics Committee has approved the trial (IR.KAUMS.MEDNT.REC.1401.003) (17 April 2022). Results will be published in peer-reviewed academic journals and the participants will be informed via phone calls.

TRIAL REGISTRATION NUMBER

IRCT20220522054958N1.

Effect of Intermittent Fasting on Glycaemic Control in Patients With Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background: Type 2 diabetes mellitus (T2DM) is a severe public health issue notably impacting human life and health expenditure. It has been observed in literature that intermittent fasting (IF) addresses diabetes and its underlying cause, which benefits people with diabetes. Therefore, this study aimed to evaluate the effectiveness of IF treatment on glycaemic control in people with T2DM compared with control group. Methods: Systematic review and meta-analysis of interventional studies among patients with T2DM with glycated haemoglobin (HbA1c) as an outcome was performed. A comprehensive search of electronic databases, including PubMed, Embase and Google Scholar, for articles published before 24 April 2022, was done. Studies reporting 24 hours of complete fasting or intermittent restricted energy intake (feeding permitted for only 4-8 hours daily, with 16-20 hours of fasting) and reporting changes in HbA1c and fasting glucose levels were eligible. Meta-analysis was performed using Cochrane's Q statistic and the I² statistical approach. Results: Eleven studies (13 arms) measuring the effect of IF on patients' HbA1c level were analysed. There was no statistically significant difference between IF and control groups (Standardized mean difference [SMD] -0.08, 95% confidence interval [CI] -0.20 to 0.04;p=0.19, I²=22%). Overall, seven studies on patients' fasting blood glucose were analysed, and the meta-analysis revealed no significant difference between the two groups i.e. IF and control groups (SMD 0.06, 95% CI -0.25 to 0.38;p=0.69, I²=76%). Conclusion: IF and usual diet pattern have no difference in terms of glycaemic control. Although, IF may be used as a preventative diet pattern in the pre-diabetic population, as it works well in the long-term to achieve controlled sugar levels. Study registration: The protocol of this study was registered in The International Prospective Register of Systematic Reviews (PROSPERO) with a registration number CRD42022328528.

Dietary patterns and cardiometabolic health: Clinical evidence and mechanism

For centuries, the search for nutritional interventions to underpin cardiovascular treatment and prevention guidelines has contributed to the rapid development of the field of dietary patterns and cardiometabolic disease (CMD). Numerous studies have demonstrated that healthy dietary patterns with emphasis on food-based recommendations are the gold standard for extending lifespan and reducing the risks of CMD and mortality. Healthy dietary patterns include various permutations of energy restriction, macronutrients, and food intake patterns such as calorie restriction, intermittent fasting, Mediterranean diet, plant-based diets, etc. Early implementation of healthy dietary patterns in patients with CMD is encouraged, but an understanding of the mechanisms by which these patterns trigger cardiometabolic benefits remains incomplete. Hence, this review examined several dietary patterns that may improve cardiometabolic health, including restrictive dietary patterns, regional dietary patterns, and diets based on controlled macronutrients and food groups, summarizing cutting-edge evidence and potential mechanisms for CMD prevention and treatment. Particularly, considering individual differences in responses to dietary composition and nutritional changes in organ tissue diversity, we highlighted the critical role of individual gut microbiota in the crosstalk between diet and CMD and recommend a more precise and dynamic nutritional strategy for CMD by developing dietary patterns based on individual gut microbiota profiles.

Fasting intervention and its clinical effects on the human host and microbiome

Experimental trials in organisms ranging from yeast to humans have shown that various forms of reducing food intake (caloric restriction) appear to increase both overall and healthy lifespan, delaying the onset of disease and slowing the progression of biomarkers of aging. The gut microbiota is considered one of the key environmental factors strongly contributing to the regulation of host health. Perturbations in the composition and activity of the gut microbiome are thought to be involved in the emergence of multiple diseases. Indeed, many studies investigating gut microbiota have been performed and have shown strong associations between specific microorganisms and metabolic diseases including overweight, obesity, and type 2 diabetes mellitus as well as specific gastrointestinal disorders, neurodegenerative diseases, and even cancer. Dietary interventions known to reduce inflammation and improve metabolic health are potentiated by prior fasting. Inversely, birth weight differential host oxidative phosphorylation response to fasting implies epigenetic control of some of its effector pathways. There is substantial evidence for the efficacy of fasting in improving insulin signaling and blood glucose control, and in reducing inflammation, conditions for which, additionally, the gut microbiota has been identified as a site of both risk and protective factors. Accordingly, human gut microbiota, both in symbiont and pathobiont roles, have been proposed to impact and mediate some health benefits of fasting and could potentially affect many of these diseases. While results from small-N studies diverge, fasting consistently enriches widely recognized anti-inflammatory gut commensals such as Faecalibacterium and other short-chain fatty acid producers, which likely mediates some of its health effects through immune system and barrier function impact.

Effect of alternate day fasting combined with aerobic exercise on non-alcoholic fatty liver disease: A randomized controlled trial

Innovative non-pharmacological lifestyle strategies to treat non-alcoholic fatty liver disease (NAFLD) are critically needed. This study compared the effects of alternate day fasting (ADF) combined with exercise to fasting alone, or exercise alone, on intrahepatic triglyceride (IHTG) content. Adults with obesity and NAFLD (n = 80, 81% female, age: 23-65 years) were randomized to 1 of 4 groups for 3 months: combination of ADF (600 kcal/2,500 kJ "fast day" alternated with an ad libitum intake "feast day") and moderate-intensity aerobic exercise (5 session per week, 60 min/session); ADF alone; exercise alone; or a no-intervention control group. By month 3, IHTG content was significantly reduced in the combination group (-5.48%; 95% CI, -7.77% to -3.18%), compared with the exercise group (-1.30%; 95% CI, -3.80% to 1.20%; p = 0.02) and the control group (-0.17%; 95% CI, -2.17% to 1.83%; p < 0.01) but was not significantly different versus the ADF group (-2.25%; 95% CI, -4.46% to -0.04%; p = 0.05). Body weight, fat mass, waist circumference, and alanine transaminase (ALT) levels significantly decreased, while insulin sensitivity significantly increased in the combination group compared with the control group. Lean mass, aspartate transaminase (AST), HbA1c, blood pressure, plasma lipids, liver fibrosis score, and hepatokines (fetuin-A, FGF-21, and selenoprotein P) did not differ between groups. Combining intermittent fasting with exercise is effective for reducing hepatic steatosis in patients with NAFLD but may offer no additional benefit versus fasting alone.

Fasting and weight loss: mobile application-based approach

BACKGROUND

The purpose of this study was to investigate the efficacy of intermittent fasting (IF) guidance, delivered through a smartphone application, in terms of engagement and weight loss.

METHODS

We performed a retrospective chart-review study of all consecutive users with overweight or obesity of the DoFasting mobile application, which integrates IF solutions for people looking to lose weight. Users with overweight and obesity at the beginning of application use, who met the inclusion criteria (entered their gender, height, and starting weight; had more than one weight entry; used the app for at least a month; had at least one active day per week with valid app-related activities) and used the application for weight loss were included in the study.

RESULTS

The final study cohort comprised 22,022 consecutive users. The short-term cohort comprised 17,221 users (8585 females and 8636 males), while 4801 users (2983 females and 1818 males) were in the long-term cohort. Long-term active users of the application lost a statistically significant amount of weight over the study period and lost more than inactive users did (2.2 [3.5] vs 1.4 [3.2], p < 0.0001; the results are shown in kilograms as medians with the interquartile range in brackets). Active and long-term users were also more likely to reduce their BMI class (p < 0.05) in comparison to non-active short-term users. A multiple regression model showed that the total length of use and active days were the most significant predictors of weight loss. In-app activities such as total fasting hours, weight logging, completing challenges, and providing feedback were also statistically significant predictors of weight loss with varying contributions.

CONCLUSION

We found that the DoFasting mobile application that implements IF is an effective tool for weight loss if used actively and sufficiently.

TRIAL REGISTRATION

This retrospective chart review study was approved by BRANY IRB in January 2022 (study ID.: 22-08-034-939).

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.

Intermittent Fasting: Potential Utility in the Treatment of Chronic Pain across the Clinical Spectrum

Dietary behavior can have a consequential and wide-ranging influence on human health. Intermittent fasting, which involves intermittent restriction in energy intake, has been shown to have beneficial cellular, physiological, and system-wide effects in animal and human studies. Despite the potential utility in preventing, slowing, and reversing disease processes, the clinical application of intermittent fasting remains limited. The health benefits associated with the simple implementation of a 12 to 16 h fast suggest a promising role in the treatment of chronic pain. A literature review was completed to characterize the physiologic benefits of intermittent fasting and to relate the evidence to the mechanisms underlying chronic pain. Research on different fasting regimens is outlined and an overview of research demonstrating the benefits of intermittent fasting across diverse health conditions is provided. Data on the physiologic effects of intermittent fasting are summarized. The physiology of different pain states is reviewed and the possible implications for intermittent fasting in the treatment of chronic pain through non-invasive management, prehabilitation, and rehabilitation following injury and invasive procedures are presented. Evidence indicates the potential utility of intermittent fasting in the comprehensive management of chronic pain and warrants further investigation.

Comparison of the Effects of Intermittent Energy Restriction and Continuous Energy Restriction among Adults with Overweight or Obesity: An Overview of Systematic Reviews and Meta-Analyses

There is considerable heterogeneity across the evidence regarding the effects of intermittent energy restriction and continuous energy restriction among adults with overweight or obesity which presents difficulties for healthcare decision-makers and individuals. This overview of systematic reviews aimed to evaluate and synthesize the existing evidence regarding the comparison of the two interventions. We conducted a search strategy in eight databases from the databases’ inception to December 2021. The quality of 12 systematic reviews was assessed with A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) and the Grading of Recommendations Assessment, Development and Evaluation (GRADE). One review was rated as high quality, 1 as moderate, 4 as low, and 6 as critically low. A meta-analysis of the original studies was conducted for comparison of primary intermittent energy restriction protocols with continuous energy restriction. Intermittent energy restriction did not seem to be more effective in weight loss compared with continuous energy restriction. The advantages of intermittent energy restriction in reducing BMI and waist circumference and improvement of body composition were not determined due to insufficient evidence. The evidence quality of systematic reviews and original trials remains to be improved in future studies.

Intermittent Energy Restriction for Weight Loss: A Systematic Review of Cardiometabolic, Inflammatory and Appetite Outcomes

Current guidelines for obesity treatment recommend reducing daily caloric intake for weight loss. However, long-term weight loss continues to be an issue in obesity management. Alternative weight loss strategies have increased in popularity, such as intermittent energy restriction (IER), a type of eating pattern with periods of fasting alternating with unrestricted eating. The effects of IER on weight loss, cardiovascular risk factors, inflammation, and appetite are not clear. The purpose of this systematic review was to analyze short- (<24 weeks) and long-term (≥24 weeks) effects of IER on anthropometric, cardiometabolic, inflammatory, and appetite outcomes in adults with overweight/obesity. PubMed, CINAHL, Embase, and PsycInfo were searched from inception to July 2020. Human randomized controlled trials (RCTs) on IER with participants with a body mass index ≥25 kg/m² were included in this review. A total of 42 articles (reporting on 27 different RCTs) were included. In short-term studies, IER showed pre-to-post treatment improvements in eight of nine studies that assessed weight. Weight outcomes were sustained in the long-term. However, no significant long-term between group differences were observed in fat mass, other anthropometric, cardiometabolic, inflammatory, or appetite outcomes. Compared to continuous energy restriction (CER), IER showed no significant long-term differences in anthropometric, cardiometabolic, inflammatory, or appetite outcomes in included studies. More long-term studies are needed to assess the benefits of IER on health outcomes.

Effects of Intermittent Fasting in Human Compared to a Non-intervention Diet and Caloric Restriction: A Meta-Analysis of Randomized Controlled Trials

Background

The popularity of applying intermittent fasting (IF) has increased as more and more people are trying to avoid or alleviate obesity and metabolic disease. This study aimed to systematically explore the effects of various IF in humans.

Methods

The randomized controlled trials (RCTs) related to IF vs. non-intervention diet or caloric restriction (CR) were retrieved in PubMed, Web of Science, Cochrane Library database, and Embase. Extraction outcomes included, but were not limited to, weight, body mass index (BMI), waist circumference (WC), fasting glucose, and triglyceride (TG).

Results

This study includes 43 RCTs with 2,483 participants. The intervention time was at least 1 month, and the median intervention time was 3 months. Contrasting results between IF and non-intervention diet showed that participants had lower weight (weighted mean difference (WMD) = 1.10, 95% CI: 0.09–2.12, p = 0.03) and BMI after IF (WMD = 0.38, 95% CI: 0.08–0.68, p = 0.01). The WC of participants after IF decreased significantly compared with the non-intervention diet (WMD = 1.02, 95% CI: 0.06–1.99, p = 0.04). IF regulated fat mass (FM) more effectively than non-intervention diet (WMD = 0.74, 95% CI: 0.17–1.31, p = 0.01). The fat-free mass of people after IF was higher (WMD = −0.73, 95% CI: (−1.45)–(−0.02), p = 0.05). There was no difference in fasting blood glucose concentrations between participants in the after IF and non-intervention diet groups. The results of insulin concentrations and HOMA-IR, though, indicated that IF was significantly more beneficial than non-intervention diet (standard mean difference (SMD) = −0.21, 95% CI: 0.02–0.40, p = 0.03, and WMD = 0.35, 95% CI: 0.04–0.65, p = 0.03, respectively). Cholesterol and TG concentrations in participants after IF were also lower than that after a nonintervention diet (SMD = 0.22, 95% CI: 0.09–0.35, p = 0.001 and SMD = 0.13, 95% CI: 0.00–0.26, p = 0.05, respectively). IF outcomes did not differ from CR except for reduced WC.

Conclusion

Intermittent fasting was more beneficial in reducing body weight, WC, and FM without affecting lean mass compared to the non-intervention diet. IF also effectively improved insulin resistance and blood lipid conditions compared with non-intervention diets. However, IF showed less benefit over CR.

Clinical application of intermittent fasting for weight loss: progress and future directions

Intermittent fasting diets have become very popular in the past few years, as they can produce clinically significant weight loss. These diets can be defined, in the simplest of terms, as periods of fasting alternating with periods of eating. The most studied forms of intermittent fasting include: alternate day fasting (0-500 kcal per 'fast day' alternating with ad libitum intake on 'feast days'); the 5:2 diet (two fast days and five feast days per week) and time-restricted eating (only eating within a prescribed window of time each day). Despite the recent surge in the popularity of fasting, only a few studies have examined the health benefits of these diets in humans. The goal of this Review is to summarize these preliminary findings and give insights into the effects of intermittent fasting on body weight and risk factors for cardiometabolic diseases in humans. This Review also assesses the safety of these regimens, and offers some practical advice for how to incorporate intermittent fasting diets into everyday life. Recommendations for future research are also presented.

Intermittent Fasting versus Continuous Calorie Restriction: Which Is Better for Weight Loss?

We conducted a systematic review and meta-analysis of randomized clinical trials and pilot trial studies to compare the effectiveness of intermittent fasting (IF) and continuous calorie restriction (CCR) in overweight and obese people. The parameters included body mass index (BMI), body weight, and other metabolism-related indicators. A systematic search in PubMed, Embase, Cochrane Library, and Web of Science was conducted up to January 2022. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were used to measure the effectiveness. Publication bias was assessed using Egger’s test. The stability of the results was evaluated using sensitivity analyses. The significance of body weight change (SMD = −0.21, 95% CI (−0.40, −0.02) p = 0.028) was more significant after IF than CCR. There was no significant difference in BMI (SMD = 0.02, 95% CI (−0.16, 0.20) p = 0.848) between IF and CCR. These findings suggest that IF may be superior to CCR for weight loss in some respects.

Can Fasting Curb the Metabolic Syndrome Epidemic?

Metabolic syndrome (MetS) represents a cluster of metabolic abnormalities that includes hypertension, central obesity, insulin resistance, and atherogenic dyslipidemia. Due to the high prevalence (around 1/3 of the world population) economic burden of MetS, there is a need for new dietary, lifestyle, and therapeutic options. Recently, fasting emerged as a dietary method proposed for controlling metabolic risk factors. Intermittent fasting (IF), or time-restricted feeding (TRF), describes an array of feeding patterns in which calorie intake is restricted to a specific time period. Hence, this review aimed to elucidate the latest data on MetS and explore the viability of simple management options, such as IF and TRF. Preclinical studies have shown how IF/TRF exerts beneficial effects on the gut microbiota, glucose and insulin metabolism, weight and visceral fat, and lipid metabolism. However, the results obtained from human studies are somewhat conflicting, as weight loss was achieved in all studies, whereas in some studies, there was no significant effect on insulin resistance, cholesterol/lipid metabolism, or blood pressure. Nevertheless, as only very few human studies were performed, there is a need for more randomized control trials on larger cohorts of patients with MetS to gather higher-yield evidence to clarify whether IF/TRF are suitable dietary patterns for this population.

Effect of Different Types of Intermittent Fasting on Biochemical and Anthropometric Parameters among Patients with Metabolic-Associated Fatty Liver Disease (MAFLD)-A Systematic Review

Metabolic-associated fatty liver disease (MAFLD), previously called non-alcoholic fatty liver disease (NAFLD), is the most common chronic liver disease worldwide. It is characterised by excessive fat accumulation in hepatocytes. Currently, no pharmacological therapy is effective for this disease, so non-pharmacological alternatives such as diet, supplementation or physical activity are being sought. For this reason, we reviewed the available databases to analyse the studies conducted to date using different modifications of intermittent fasting among patients with MAFLD. Eight studies using this dietary strategy were included in this review. The results obtained in the different trials are varied and do not allow a clear determination of the effect of the different types of intermittent fasting on anthropometric and biochemical parameters among patients with MAFLD. However, this type of diet seems to show some therapeutic potential, but further studies are needed.

Effect of Epidemic Intermittent Fasting on Cardiometabolic Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Intermittent fasting (IF) has gained attention as a promising diet for weight loss and dysmetabolic diseases management. This systematic review aimed to investigate the effects of IF on cardiometabolic risk factors (CMRFs). A systematic literature search was carried out using three electronic databases, namely PubMed, Embase, and the Cochrane Library, until October 2020. Randomized controlled trials that compared the IF intervention with a control group diet were included. Fourteen effect sizes were expressed as weighted mean difference (WMD) using a fixed-effects model and 95% confidence intervals (CI). Compared to the ones within control groups, participants exposed to the IF intervention reduced their body weight (WMD, −1.78 kg; 95% CI, −2.21 to −1.35; p <0.05), waist circumference (WMD, −1.19 cm; 95% CI, −1.8 to −0.57; p <0.05), fat mass (WMD, −1.26 kg; 95% CI, −1.57 to −0.95; p <0.05), body mass index (WMD, −0.58 kg/m²; 95% CI, −0.8 to −0.37; p <0.05), systolic blood pressure (WMD, −2.14 mmHg; 95% CI: −3.54 to −0.73; p <0.05), diastolic blood pressure (WMD: −1.38 mmHg, 95% CI, −2.35 to −0.41, p <0.05), fasting blood glucose (WMD: −0.053 mmol/L; 95% CI: −0.105 to 0.001; p <0.05), fasting insulin (WMD, −0.8 mIU/L; 95% CI, −1.15 to −0.44; p <0.05), insulin resistance (WMD, −0.21; 95% CI, −0.36 to −0.05; p <0.05), total cholesterol (WMD, −0.10 mmol/L; 95% CI, −0.17 to −0.02; p <0.05), and triglycerides (WMD, −0.09 mmol/L; 95% CI, −0.13 to −0.04; p <0.05). No effects were observed for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, or glycosylated hemoglobin. This meta-analysis supports the role of IF in improving the component composition of CMRFs, including weight, waist circumference, fat mass, BMI, blood pressure, total cholesterol, triglycerides, fasting insulin, and insulin resistance, compared to a control group diet. Further research on IF interventions should take into account long-term and well-designed administration to draw definitive conclusions.

Cardiometabolic Benefits of Intermittent Fasting

This review aims to summarize the effects of intermittent fasting on markers of cardiometabolic health in humans. All forms of fasting reviewed here-alternate-day fasting (ADF), the 5:2 diet, and time-restricted eating (TRE)-produced mild to moderate weight loss (1-8% from baseline) and consistent reductions in energy intake (10-30% from baseline). These regimens may benefit cardiometabolic health by decreasing blood pressure, insulin resistance, and oxidative stress. Low-density lipoprotein cholesterol and triglyceride levels are also lowered, but findings are variable. Other health benefits, such as improved appetite regulation and favorable changes in the diversity of the gut microbiome, have also been demonstrated, but evidence for these effects is limited. Intermittent fasting is generally safe and does not result in energy level disturbances or increased disordered eating behaviors. In summary, intermittent fasting is a safe diet therapy that can produce clinically significant weight loss (>5%) and improve several markers of metabolic health in individuals with obesity.

Intermittent fasting versus continuous energy-restricted diet for patients with type 2 diabetes mellitus and metabolic syndrome for glycemic control: A systematic review and meta-analysis of randomized controlled trials

AIMS

To compare the safety of intermittent fasting (IF) with that of continuous energy-restricted diets (CERD) in patients with T2DM and metabolic syndrome who were overweight or obese and assess their effects on glycemic control and weight loss.

MATERIALS AND METHODS

We searched MEDLINE (Ovid), Embase, and SINOMED databases up to September 13, 2020. The major outcome was glycemic control and secondary outcomes were change in weight, fasting insulin, and lipid profile.

RESULTS

Of 84 retrieved studies, 5 met our inclusion criteria. Of these, four studies comprising 355 participants were included in the meta-analysis. Based on changes in HbA1c (-0.06, 95% confidence interval [CI] -0.27 to 0.16) and fasting plasma glucose (-0.27, 95% CI -0.76 to 0.22), IF and CERD had similar effects on glycemic control. Moreover, IF had a better effect on weight loss (-1.70, 95% CI -3.28 to -0.11 kg). Patients in both groups experienced similar improvements in fasting insulin and lipid profile as well as similar hypoglycemic events.

CONCLUSIONS

IF is a safe diet pattern and could be implemented for patients with T2DM or metabolic syndrome. Further studies with a larger sample size are needed to verify the effectiveness and safety of IF in patients with T2DM.

Effect of intermittent and continuous caloric restriction on Sirtuin1 concentration depends on sex and body mass index

BACKGROUND & AIMS

The favorable effect of caloric restriction (CR) on health span is well known and partly mediated by the sirtuin system. Sirtuin1, a regulator of energy homeostasis in response to nutrient availability, is activated by CR. We therefore investigated effects of two different CR regimens on Sirtuin1 concentrations.

METHODS & RESULTS

The study included 112 abdominally obese subjects, randomized to intermittent or continuous CR for 1 year. Blood samples and anthropometric measures were collected at baseline and after 12 months. Sirtuin1 concentrations were measured by ELISA. Sirtuin1 correlated significantly to BMI at baseline (r = .232, p = 0.019). Mean reduction in body-weight was 8.0 and 9.0 kg after intermittent and continuous CR, respectively. After 1 year, no significant between-group differences in Sirtuin1 levels were observed according to regimen (p = 0.98) and sex (p = 0.41). An increase in median Sirtuin1 concentrations (pg/mL) [25, 75 percentiles] from baseline was observed after intermittent CR in the total population (884 [624, 1285] vs.762 [530, 1135]; p = 0.041), most marked in men (820 [623, 1250] vs. 633 [524, 926]; p = 0.016). Improvement in BMI after 1 year correlated to Sirtuin1 changes, but varied according to sex. In women, Spearman's rho = .298, p = 0.034, with stronger correlation in the intermittent CR group (r = .424, p = 0.049). In men, there was an inverse relation to Sirtuin1 changes, only in the intermittent CR group (r = -.396, p = 0.045).

CONCLUSIONS

Effects on Sirtuin1 concentrations after 1 year of CR are sex and BMI-related. Intermittent CR regimen affected Sirtuin1 to a stronger extent than continuous CR, suggesting individualized dietary intervention.