Ramadan model of intermittent fasting for 28 d had no major effect on body composition, glucose metabolism, or cognitive functions in healthy lean men

The optimal time restricted eating interventions for blood pressure, weight, fat mass, glucose, and lipids: A meta-analysis and systematic review

BACKGROUND

No previous systematic review or meta-analysis has evaluated the effect of optimal time-restricted eating (TRE) interventions on cardiovascular (CVD) risk factors. This meta-analysis aimed to illustrate the effect of a suitable TRE on CVD risk factors.

METHODS

A systematic review was performed to identify trials reporting the effects of TRE, relative to non-diet controls, on CVD risk factors in humans. A random-effects model was used to evaluate the effect sizes, and the results are expressed as the mean difference (MD) and 95% confidence intervals (CIs). Subgroup analyses were performed to examine the influence of the study population, age, duration of intervention, and baseline mean BMI on the CVD indexes.

RESULTS

TRE intervention significantly reduced systolic pressure (SBP) (MD: -3.45 mmHg; 95%CI:(-6.20,-0.71) mmHg; P = 0.01), body weight (MD: -1.63 Kg; 95%CI:(-2.09,-1.17) Kg; P<0.001), body mass index (BMI) (MD: -0.47 Kg/m2; 95% CI: (-0.72, -0.22) Kg/m2; P<0.001), and fat mass (MD: -0.98 Kg; 95% CI: (-1.51,-0.44) Kg; P<0.001), and reduced blood glucose levels. Based on the results of subgroup analysis, this meta-analysis identified the optimal TRE for BP (with a 6 h feeding window, last eating time point at 6-8 PM, and male participants with obesity and aged ≥ 45 years), obesity (with a 6 h feeding window, last eating time point at 6-8 PM, and female participants aged ≥ 45 years), lipids (with an 8 h feeding window, last eating time point at 6-8 PM, and male participants aged < 45 years), and glucose (with a 10-12 h feeding window, last eating time point before 6 PM, and female participants aged < 45years).

CONCLUSIONS

Relative to a non-diet control, TRE is effective for the improvement of CVD risks. Moreover, individual TRE interventions should be developed for different populations to achieve the most effective health improvement for CVD risk factors.

The interactions between energy homeostasis and neurovascular plasticity

Food intake and energy expenditure are sensed and processed by multiple brain centres to uphold energy homeostasis. Evidence from the past decade points to the brain vasculature as a new critical player in regulating energy balance that functions in close association with the local neuronal networks. Nutritional imbalances alter many properties of the neurovascular system (such as neurovascular coupling and blood-brain barrier permeability), thus suggesting a bidirectional link between the nutritional milieu and neurovascular health. Increasing numbers of people are consuming a Western diet (comprising ultra-processed food with high-fat and high-sugar content) and have a sedentary lifestyle, with these factors contributing to the current obesity epidemic. Emerging pharmacological interventions (for example, glucagon-like peptide 1 receptor agonists) successfully trigger weight loss. However, whether these approaches can reverse the detrimental effects of long-term exposure to the Western diet (such as neurovascular uncoupling, neuroinflammation and blood-brain barrier disruption) and maintain stable body weight in the long-term needs to be clarified in addition to possible adverse effects. Lifestyle interventions revert the nutritional trigger for obesity and positively affect our overall health, including the cardiovascular system. This Perspective examines how lifestyle interventions affect the neurovascular system and neuronal networks.

Effects of intermittent fasting combined with exercise on serum leptin and adiponectin in adults with or without obesity: a systematic review and meta-analysis of randomized clinical trials

Context

Intermittent fasting (IF) and exercise training (Exe) have been evaluated in several studies for improving cardiometabolic biomarkers related to weight loss. However, further investigation is required to understand the potential effects on leptin and adiponectin concentrations. IF protocols have been shown to be efficient in improving adipokines, but further research is required to determine whether or not IF regimens combined with Exe are superior to Exe alone.

Objective

The aim of this study was to determine whether or not interventions combining IF plus Exe are more effective than Exe only for improving serum leptin and adiponectin in adults with and without obesity.

Data extraction

A systematic review and meta-analysis was performed by searching PubMed, Scopus, and Web of Science databases up to August 2023 for randomized clinical trials that determined the effects of IF plus Exe vs. Exe alone (control) on body weight, serum leptin, and serum adiponectin. Analyses were conducted for IF plus Exe vs. Exe alone to calculate weighted mean differences (WMD) and standardized mean differences (SMD).

Analysis

The current meta-analysis included 6 studies with a total sample of 153 participants, with intervention durations ranging from three days to 52 weeks. IF plus Exe elicited significantly larger decreases in leptin levels [SMD = -0.47, p = 0.03], which were accompanied by weight loss [WMD = -1.25 kg, p = 0.05], as compared with exercise-only interventions, but adiponectin did not differ between the two [SMD = 0.02, p = 0.9].

Conclusion

IF combined with Exe reduced leptin significantly, but did not change adiponectin levels, when compared to exercise only. Perhaps these reductions in leptin levels may have been associated with weight loss; however, due to the small number of included studies and the high heterogeneity in the weight loss outcomes, this result is uncertain.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023460735.

Effects of Modified Ramadan Fasting on Mental Well-Being and Biomarkers in Healthy Adult Muslims - A Randomised Controlled Trial

BACKGROUND

Ramadan fasting has seen increased attention in research, often with inconsistent findings. This study aims to investigate whether dietary and lifestyle modifications during Ramadan can improve well-being and health in healthy adult Muslims.

METHOD

A randomised controlled trial with two parallel groups was conducted in an outpatient clinic of a university hospital in Essen, Germany, in 2016. Healthy adult Muslims (n = 114) aged 18-60 years were randomised to a modified fasting group; i.e., they received educational material prompting dietary and lifestyle modifications pre-Ramadan, and a control group who undertook Ramadan fasting as usual. Primary outcome was quality of life (WHO-5 Well-Being Index). Secondary outcomes included sleep quality, spirituality, and mindfulness (all self-report), body weight, body mass index, body fat, waist circumference, hip circumference, blood pressure, and heart rate, as well as blood serum biomarkers. Safety was examined via adverse events.

RESULTS

The modified fasting group reported significantly higher quality of life (WHO-5) compared to the control after Ramadan (MD 5.9; 95% CI, 0.02-11.8; p < 0.05). Group differences in favour of the modified fasting were also found for satisfaction with health (MD 5.9, 95% CI 0.19-11.67), ease of life (MD 4.1, 95% CI 0.38-7.80) and mindfulness (MD 7.6, 95% CI 2.68-12.52), reductions in weight (MD, - 0.9 kg; 95% CI - 1.39 to - 0.42), BMI (MD - 0.3 kg/m2, 95% CI - 0.50 to - 0.15), hip circumference (MD - 0.3 kg/m2, 95% CI - 0.50 to - 0.15), and diastolic blood pressure (MD - 2.8 mmHg, 95% CI - 5.15 to - 0.43). About 60% of participants reported adverse events, mostly headaches/migraines, dizziness/fatigue, common cold, and gastrointestinal symptoms, with no group differences. One serious non-related adverse event each occurred in both groups.

CONCLUSION

Pre-Ramadan dietary and lifestyle advice can lead to short-term improvements in mental and physical well-being of adult Muslims observing Ramadan. As such, this study demonstrates the potential benefits of culturally appropriate health interventions in a religious context.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier NCT02775175).

Effects of combined dietary intervention and physical-cognitive exercise on cognitive function and cardiometabolic health of postmenopausal women with obesity: a randomized controlled trial

BACKGROUND

Postmenopausal women with obesity are markedly at risk of cognitive impairment and several health issues. Emerging evidence demonstrated that both diet and exercise, particularly physical-cognitive exercise are involved in cognitive and health benefits. However, the comparative effect of diet, exercise, and combined interventions in postmenopausal women with obesity on cognition and cardiometabolic health is still lacking. Identifying the effective health promotion program and understanding changes in cardiometabolic health linking these interventions to cognition would have important medical implications. This RCT aimed to examine the effect of single and combined interventions of diet and exercise on cognitive function and cardiometabolic health in postmenopausal women with obesity.

METHODS

Ninety-two postmenopausal women with obesity were randomly assigned to diet group (intermittent fasting 2 days/week, 3 months), exercise group (physical-cognitive exercise 3 days/week, 3 months), combined group, or control group (n = 23/group). All cognitive outcomes and cardiometabolic outcomes were measured at baseline and post-3 months. Primary outcomes were executive functions, memory, and plasma BDNF levels. Secondary outcomes were global cognition, attention, language domain, plasma adiponectin levels, IL-6 levels, metabolic parameters, and physical function.

RESULTS

At the end of the 3-month intervention, the exercise and combined group demonstrated significant memory improvement which was accompanied by significant improvements in plasma BDNF level, insulin levels, HOMA-IR, %body fat, and muscle strength when compared to controls (p < 0.05). Only the combined intervention group demonstrated a significant improvement in executive function and increased plasma adiponectin levels when compared to control (p < 0.05). Surprisingly, no cognitive improvement was observed in the diet group (p > 0.05). Significant reduction in cholesterol levels was shown in the diet and combined groups when compared to controls (p < 0.05). Among the three intervention groups, there were no significant differences in all cognitive outcomes and cardiometabolic outcomes (p > 0.05). However, all three intervention groups showed significant improvements in plasma BDNF levels, weight, BMI, WHR, fat mass, and predicted VO2 max, when compared to control (p < 0.05).

CONCLUSION

These findings suggest that combined physical-cognitive exercise and dietary intervention are promising interventions to improve cognition and obesity-related complications of postmenopausal women with obesity.

TRIAL REGISTRATION

NCT04768725 ( https://clinicaltrials.gov ) 24th February 2021.

The impact of continuous calorie restriction and fasting on cognition in adults without eating disorders

Research into the effects of calorie restriction continues to intrigue those interested in whether it may allow humans to live longer and healthier lives. Animal studies of continuous calorie restriction (CCR) and fasting have demonstrated substantial advantages to health and longevity. However, concerns remain about the impact of restricting calorie intake on human health and cognition. Given the emerging evidence of cognitive impairments in eating disorders, studies investigating restricted calorie intake in healthy humans (in an ethical way) may also have implications for understanding restrictive eating disorders. In this review, the published literature on the impact of CCR and fasting on cognitive function in healthy human participants is synthesized. Of the 33 studies of CCR and fasting in humans identified, 23 demonstrated significant changes in cognition. Despite variation across the cognitive domains, results suggest CCR benefits inhibition, processing speed, and working memory, but may lead to impairments in cognitive flexibility. The results of fasting studies suggest fasting is associated with impairments in cognitive flexibility and psychomotor abilities. Overall, the results of these studies suggest the degree (ie, the severity) of calorie restriction is what most likely predicts cognitive improvements as opposed to impairments. For individuals engaging in sustained restriction, this may have serious, irreversible consequences. However, there are mixed findings regarding the impact of CCR and fasting on this aspect of human functioning, suggesting further research is required to understand the costs and benefits of different types of calorie restriction.

Impact of Ramadan Fasting on Cardiometabolic and InflammatoryBiomarkers among Saudi Adults with Diabetes

BACKGROUND AND AIMS

Diabetes is prevalent in Saudi Arabia. As dietary concerns are central in patients with diabetes, the impact of fasting on health during Ramadan is potentially significant. Decreased meal frequency and changes in food type and amount affect body weight and metabolic profiles. This study aimed to investigate the association between Ramadan fasting and anthropometric measurements and cardiometabolic and inflammatory biomarkers in Saudi adults with diabetes.

METHODS

Sixty-eight Saudi adults with diabetes, admitted at the University Diabetes Centre in Riyadh, Saudi Arabia, were enrolled in this study. Participants were evaluated at the following time points: Six weeks before Ramadan (pre-fasting) and at least 15 days after the initiation of Ramadan (peri-fasting). Anthropometric measurements and cardiometabolic and inflammatory biomarker levels were assessed during both visits.

RESULTS

After accounting for confounding factors, Ramadan fasting was found to be associated with reduced body weight (kg), waist circumference (cm), and hip circumference (cm). Increased log high-density lipoprotein-cholesterol and decreased log interleukin 6 and C-reactive protein levels were observed.

CONCLUSIONS

Ramadan fasting was associated with increased HDL-C levels and decreased anthropometric measurements and inflammatory cytokine levels. These results support the beneficial role of Ramadan fasting in reducing cardiometabolic abnormalities and inflammation in adults with diabetes.

Effects of intermittent fasting combined with physical exercise on cardiometabolic outcomes: systematic review and meta-analysis of clinical studies

CONTEXT

Different intermittent fasting (IF) protocols have been proven to be efficient in improving cardiometabolic markers, but further research is needed to examine whether or not combining IF regimens plus physical exercise is superior to control diets (ie, nonfasting eating) plus physical exercise in this setting.

OBJECTIVE

The aim of this study was to determine whether or not combining IF plus exercise interventions is more favorable than a control diet plus exercise for improving cardiometabolic health outcomes.

DATA SOURCE

PubMed, Scopus, and Web of Science were comprehensively searched until April 2023.

DATA EXTRACTION

Electronic databases were searched for clinical trials that determined the effect of IF plus exercise vs a control diet plus exercise on body weight, lipid profile (high-density lipoprotein [HDL], low-density lipoprotein [LDL], triglycerides, and total cholesterol), and systolic and diastolic blood pressure (SBP and DBP, respectively). Analyses were conducted for IF plus exercise vs a nonfasting diet plus exercise to calculate weighted mean differences (WMDs).

DATA ANALYSIS

The meta-analysis included a total of 14 studies, with a total sample of 360 adults with or without obesity. The duration ranged from 4 to 52 weeks. IF plus exercise decreased body weight (WMD = -1.83 kg; P = 0.001), LDL (WMD = -5.35 mg/dL; P = 0.03), and SBP (WMD = -2.99 mm Hg; P = 0.003) significantly more than a control diet plus exercise. HDL (WMD = 1.57 mg/dL; P = 0.4) and total cholesterol (WMD = -2.24 mg/dL; P = 0.3) did not change significantly for IF plus exercise vs a control diet plus exercise, but there was a trend for reducing triglycerides (WMD = -13.13 mg/dL; P = 0.07) and DBP (WMD = 2.13 mm Hg; P = 0.05), which shows clinical magnitude.

CONCLUSION

IF plus exercise improved some cardiometabolic outcomes (body weight, blood pressure, and lipid profile) compared with a control diet plus exercise.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023423878.

Aptitude measurement: is measurement validity compromised in the morning

The purpose of the present study was to evaluate the reliability and validity of the General Aptitude Test (GAT), a national instrument for the measurement of aptitude/achievement in the Kingdom of Saudi Arabia as a function of daytime testing. Participants were 722 students who took on the GAT across morning and evening administrations in a within-person pre-post design. Participants were matched for gender, parental education, and test center characteristics (i.e., size). The GAT was tested for its psychometric properties and its measurement invariance across time of day. Results pointed to a significant misfit using an exact invariance protocol. Specifically, there was a large number of non-invariant items pointing to Differential Item Functioning (DIF). Second, internal consistency reliabilities were consistently lower during morning testing compared to evening testing as evidenced using both statistical and visual means. Concerns about dimensionality were also raised for the morning compared to the evening administration. Last, comparison of performance levels indicated that morning testing was associated with significant decrements in performance across all domains compared to performance levels during evening testing. The results have implications for the validity of measurement and public testing policy if test validity during morning administration is compromised.

The Effect of Ramadan Intermittent Fasting on Food Intake, Anthropometric Indices, and Metabolic Markers among Premenopausal and Postmenopausal Women: A Cross-Sectional Study

Background and objectives: Ramadan intermittent fasting (RIF) is a monthlong practice in which Muslims fast during the whole day from sunrise to sunset. During this month, fasting people change their dietary behavior and alter their eating hours from day to night. The objective of the current study was to examine the effect of RIF on dietary consumption, anthropometric indices, and metabolic markers in healthy premenopausal (PRE-M) and postmenopausal (POST-M) Saudi women. Materials and Methods: The study included 62 women (31 PRE-M, 21-42 years, and 31 POST-M, 43-68 years). A structured questionnaire was used to collect socioeconomic data. Physical activity, anthropometric, dietary, and biochemical assessments were assessed before and at the end of the third week of Ramadan. Results: Socioeconomic data varied among participants. For both groups, observing RIF was associated with significantly (at either p ≤ 0.01 or p ≤ 0.05) lower intake of calories, macronutrients, minerals (excluding Na), and vitamins than before RIF. For the PRE-M group, the percentage of overweight participants decreased significantly (p ≤ 0.01) during Ramadan, while the percentage of obese participants remained unchanged. In contrast, for the POST-M group, the percentage of overweight participants increased significantly (p ≤ 0.05) during Ramadan, but dropped at the end of Ramadan. Following RIF, waist-to-hip ratio, body fat, and fat mass (FM) decreased in both groups. High-density lipoprotein cholesterol (HDL-C), fasting blood glucose (FBG), triglycerides (TG), and blood pressure (SBP, DBP) were generally maintained at acceptable normal levels in most participants before and at the end of RIF. However, low-density lipoprotein cholesterol (LDL-C) at the end of RIF was significantly lower than before, particularly in POST-M women. Age, occupation, and monthly income were the most important predictors for the changes in nutritional status and body fat upon RIF. Conclusions: observing RIF by PRE-M and POST-M Saudi women was associated with significant improvements in variable health indicators, with a few exceptions, and may help lower risk factors for chronic diseases, particularly among POST-M women. However, further studies with a larger sample size are required to determine and confirm the exact effect of RIF on these groups.

Impact of Nighttime Food Consumption and Feasibility of Fasting during Night Work: A Narrative Review

Shift work has been associated with an increased risk of developing chronic non-communicable diseases, such as obesity. The reduction in overnight fasting and its physiological consequences seem to affect the metabolic health of shift workers, but little has been discussed regarding the feasibility and implications of maintaining a night-long fast during work. This narrative review aims to discuss the impact of eating behavior on the reduction of overnight fasting in shift workers, as well as possible nutritional strategies involving fasting that have been tested for shift workers, to contribute to the establishment of nutritional guidelines for them. We used various databases and search engines to retrieve relevant articles, reviews, and investigations. Despite the potential benefits of overnight fasting for other groups, few studies have investigated this approach in the context of shift work. Generally, it seems to be a feasible and metabolically beneficial strategy for shift workers. However, it is essential to investigate the potential risks and benefits of reducing the fasting time for shift workers, considering social, hedonic, and stress-related factors. Furthermore, randomized clinical trials are necessary to establish safe and feasible strategies for shift workers to practice different fasting windows.

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.

Intermittent fasting and immunomodulatory effects: A systematic review

Introduction

strategy of periodic food restriction and fixed eating windows, could beneficially modify individuals by losing body weight, regulating glucose or lipid metabolism, reducing blood pressure, and modulating the immune system. Specific effects of IF and its mechanisms have not yet been assessed collectively. Thus, this systematic review aims to summarize and compare clinical trials that explored the immunomodulatory effects of IF.

Methods

After screening, 28 studies were included in this systematic review.

Results

In addition to weight loss, IF could benefit health subjects by strengthening their circadian rhythms, migrating immune cells, lower inflammatory factors, and enriching microbials. In addition of the anti-inflammatory effect by regulating macrophages, protection against oxidative stress with hormone secretion and oxidative-related gene expression plays a key beneficial role for the influence of IF on obese subjects.

Discussion

Physiological stress by surgery and pathophysiological disorders by endocrine diseases may be partly eased with IF. Moreover, IF might be used to treat anxiety and cognitive disorders with its cellular, metabolic and circadian mechanisms. Finally, the specific effects of IF and the mechanisms pertaining to immune system in these conditions require additional studies.

Time-restricted feeding and cognitive function in sedentary and physically active elderly individuals: Ramadan diurnal intermittent fasting as a model

Objectives

This study aimed to investigate the effects of Ramadan diurnal intermittent fasting (RDIF) on cognitive performance, sleep quality, daytime sleepiness, and insomnia in physically active and sedentary elderly individuals.

Methods

A total of 58 participants (62.93 ± 3.99 years) were assigned to one of the following two groups: a sedentary group (control group) who observed Ramadan (n = 32) and a physically active group (n = 26) who continued to train while observing Ramadan. Participants were assessed 2 weeks before Ramadan and during the fourth week of Ramadan. On each occasion, participants completed a digital assessment of their cognitive performance and responded to the Pittsburgh sleep quality index (PSQI), the insomnia severity index (ISI) and the Epworth sleepiness scale (ESS) questionnaires to assess sleep parameters.

Results

Compared to before Ramadan, performance in executive function (p = 0.035), attention (p = 0.005), inhibition (p = 0.02), associative memory (p = 0.041), and recognition memory (p = 0.025) increased significantly during Ramadan in the physically active group. For the sedentary group, associative learning performance decreased (p = 0.041), whilst performances in the remaining domains remained unchanged during Ramadan. Global PSQI, ISI, and ESS scores indicated both groups suffered from poor sleep quality and excessive daytime sleepiness, with significantly higher negative effects of RDIF observed in the sedentary group.

Conclusion

Older adults who continue to train at least three times per week during Ramadan may improve their cognitive performance, despite the impairment of sleep quality. Future studies in older adults during Ramadan including objective measures of sleep (e.g., polysomnography, actigraphy) and brain function (e.g., functional magnetic resonance imaging) are warranted.

Effects of 10-Day Complete Fasting on Physiological Homeostasis, Nutrition and Health Markers in Male Adults

Fasting shows great potential in preventing chronic diseases and has to be surmounted under some extraordinary circumstances. This study aimed to investigate the safety, time effects of metabolic homeostasis and health indexes during prolonged fasting. Thirteen participants were recruited to conduct a 10-day complete fasting (CF) in a controlled health research building under medical supervision including 3-day Baseline (BL), 10-day CF, 4-day calorie restriction (CR) and 5-day full recovery (FR). Body healthy status was assessed by surveying pulse, blood pressure, body weight (BW), blood glucose and ketones, body composition and nutritional and biochemistry indexes at different times. BW declined about 7.28 kg (−9.8%) after 10-day CF, accompanied by increased pulse and decreased systolic blood pressure, but there were no changes to the myocardial enzymogram. Body composition analysis showed fat mass was constantly lost, but lean mass could recover after CR. The energy substrate switch from glucose to ketone occurred and formed a stable dynamic balance between 3–6 days of CF. The lipid metabolism presented increased total cholesterol, LDL-C, ApoA1 and almost no changes to TG and HDL-C. Prolonged CF did not influence liver function, but induced a slight decrease of kidney function. The interesting results came from the marked increase of lipid-soluble vitamins and a significant decrease of sodium and chlorine. Adults could well tol-erate a 10-day CF. A new metabolic homeostasis was achieved. No vitamins but NaCl supplement should be considered. These findings provide evidence to design a new fasting strategy for clinical practice.

Changes in dietary intake, chronotype and sleep pattern upon Ramadan among healthy adults in Jeddah, Saudi Arabia: A prospective study

Background

Notable lifestyle changes can occur in Ramadan due to the sudden shift in eating routine with fasting during daylight hours. This study aimed to examine the changes in dietary intakes, chronotype, sleep pattern, and physical activity level before and during Ramadan in healthy adults.

Methods

This study was conducted in Jeddah city, Saudi Arabia, and convenience sampling was used. To compare dietary, chronotype and sleep pattern changes before and during Ramadan, data were collected in two separate periods: the first period was 2 months before Ramadan, and the second period was during the last 3 weeks of Ramadan. Dietary intake was assessed using 24-h food recall and chronotype using Morningness-Eveningness Questionnaire. Daytime sleepiness and sleep duration were assessed using the Epworth sleepiness scale and a sleep diary for seven consecutive days, respectively. Anthropometric measurements were also taken across the study periods.

Results

A total of 115 adults (96 females and 19 males) were included in the study. Significant increases in daily calorie and carbohydrate intakes during Ramadan than before Ramadan were noted (calorie intake: 1,482.9 ± 536.4 kcal/day before Ramdan vs. 1,635.5 ± 635.1 kcal/day during Ramadan; carbohydrate intake: 180.8 ± 72.1 g/day before Ramadan vs. 202.6 ± 88.7 g/day during Ramadan; p < 0.05). Chronotypes and daytime sleepiness were also associated significantly with Ramadan fasting. A significant slight reduction in body weight during Ramadan was observed (66.4 ± 18.1 kg before Ramdan vs. 66.1 ± 17.8 kg before Ramadan and during Ramadan, respectively; p < 0.05).

Conclusion

This study indicates that Ramadan diurnal fasting was associated with greater calorie and carbohydrate intake, changes in chronotype, and daytime sleepiness. The study also suggests that Ramadan diurnal fasting model may be a promising weight loss strategy.

The impact of Ramadan during COVID-19 confinement on weight, dietary, and lifestyle habits in the Kingdom of Saudi Arabia: a cross-sectional study

Severe procedures were undertaken globally because of the COVID-19 pandemic to overcome the spread of the disease and to prevent catastrophic results affecting the health care system including social distancing, lockdowns, and quarantines. Despite the widely known health benefits of Ramadan fasting, there was a general concern regarding the lifestyle of people during Ramadan 2020 that accompanied the period of COVID-19 pandemic and the home confinement applied. The main objective for the current cross-sectional investigation was to investigate the influence of Covid-19 lockdown during Ramadan fasting on weight change on 481 participants in Saudi Arabia. Identifying the contributing risk factors to weight gain were also addressed. Around 42% of the participants had gained weight and around 38% of the participants had lost weight. Physical activity level was shown to be considered as a protective factor against weight gain (OR = 1.03 with P = 0.008), while increasing the number of meals and not adapting healthy cooking methods can both be considered as contributing factors to weight gain (OR = 1.03 with P = 0.009, and OR = 1.03 with P = 0.004, respectively). Assessing these changes during Ramadan of COVID-19 quarantine provided valuable perspective on the health and wellbeing of Saudi Arabia citizens. These findings should be considered in future studies to explore the persistence of Covid-19 related weight status and habit change.

Effects of Walking Football During Ramadan Fasting on Heart Rate Variability and Physical Fitness in Healthy Middle-Aged Males

This study aimed to investigate the effect of a walking football (WF) program during Ramadan fasting (RF) on heart rate variability (HRV) indices, body composition, and physical fitness in middle-aged males. Thirty-one healthy sedentary men were randomized to WF (n = 18) and control (n = 13) groups. Both groups participated in RF. The WF group were involved in a training program (small-sided games) of three sessions a week during RF. The time and frequency domains of HRV, body composition, handgrip, lumbar strength, Modified Agility Test (MAT), and 6-minute walk test (6MWT) were measured before Ramadan (BR), during Ramadan (DR), and after Ramadan (AR). We reported that RF has significantly altered some parameters of HRV DR; the mean HR decreased while the mean RR, LF, and HF increased. WF had a significant effect on HRV and mean HR DR compared with BR and AR decreased while mean RR, HF and LF increased. DR, body mass decreased in both groups, while body mass index (BMI) decreased and lean mass increased only in WF group. Lower body mass and BMI levels were reported AR only in WF group. Physical capacity improved AR, compared with BR, only in the WF group with longer distance in 6MWT, shorter time(s) in MAT, and higher lumbar strength levels. We conclude that RF increases parasympathetic system activity. WF practice during RF is safe and might improve body composition, physical fitness, autonomic cardiac function, and physical fitness in middle-aged males.

Once-daily feeding is associated with better health in companion dogs: results from the Dog Aging Project

A variety of diets have been studied for possible anti-aging effects. In particular, studies of intermittent fasting and time-restricted feeding in laboratory rodents have found evidence of beneficial health outcomes. Companion dogs represent a unique opportunity to study diet in a large mammal that shares human environments. The Dog Aging Project has been collecting data on thousands of companion dogs of all different ages, sizes, and breeds since 2019. We leveraged this diverse cross-sectional dataset to investigate associations between feeding frequency and cognitive function (n = 10,474) as well as nine broad categories of health conditions (n = 24,238). Controlling for sex, age, breed, and other potential confounders, we found that dogs fed once daily rather than more frequently had lower mean scores on a cognitive dysfunction scale, and lower odds of having gastrointestinal, dental, orthopedic, kidney/urinary, and liver/pancreas disorders. Therefore, we find that once-daily feeding is associated with better health in multiple domains. Future research with longitudinal data can provide stronger evidence for a possible causal effect of feeding frequency on health in companion dogs.

The neuroprotective effects of intermittent fasting on brain aging and neurodegenerative diseases via regulating mitochondrial function

Intermittent fasting (IF) has been studied for its effects on lifespan and the prevention or delay of age-related diseases upon the regulation of metabolic pathways. Mitochondria participate in key metabolic pathways and play important roles in maintaining intracellular signaling networks that modulate various cellular functions. Mitochondrial dysfunction has been described as an early feature of brain aging and neurodegeneration. Although IF has been shown to prevent brain aging and neurodegeneration, the mechanism is still unclear. This review focuses on the mechanisms by which IF improves mitochondrial function, which plays a central role in brain aging and neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. The cellular and molecular mechanisms of IF in brain aging and neurodegeneration involve activation of adaptive cellular stress responses and signaling- and transcriptional pathways, thereby enhancing mitochondrial function, by promoting energy metabolism and reducing oxidant production.

The Implication of Physiological Ketosis on The Cognitive Brain: A Narrative Review

Optimal cognitive functions are necessary for activities of daily living and self-independence. Cognitive abilities are acquired during early childhood as part of progressive neurodevelopmental milestones; unfortunately, regressive changes can occur as part of physiological aging, or more ominously, pathological diseases, such as Alzheimer’s disease (AD). Cases of AD and its milder subset, mild cognitive impairment (MCI), are rising and would impose a burdensome impact beyond the individual level. Various dietary and nutritional approaches have potential for promising results in managing cognitive deterioration. Glucose is the core source of bioenergy in the body; however, glucose brain metabolism could be affected in aging cells or due to disease development. Ketone bodies are an efficient alternate fuel source that could compensate for the deficient glycolytic metabolism upon their supra-physiologic availability in the blood (ketosis), which, in turn, could promote cognitive benefits and tackle disease progression. In this review, we describe the potential of ketogenic approaches to produce cognitive benefits in healthy individuals, as well as those with MCI and AD. Neurophysiological changes of the cognitive brain in response to ketosis through neuroimaging modalities are also described in this review to provide insight into the ketogenic effect on the brain outside the framework of purely molecular explanations.

Effect of Intermittent Fasting (18/6) on Energy Expenditure, Nutritional Status, and Body Composition in Healthy Adults

Objective

This study was aimed at evaluating the effect of intermittent fasting of Ramadan on resting energy expenditure (REE), body composition, and nutritional status.

Methods

The study was conducted on a total of 27 adults (16 females, 11 males) who were fasting (18 h) in the Ramadan month (May 6–June 3) of 2019. REE was measured using the indirect calorimeter. Dietary energy and nutrient intakes were evaluated by 3-day food records in baseline and post-Ramadan. Body composition and some metabolic parameters were analyzed simultaneously with REE measurements. All measurements were performed two times at baseline, and post-Ramadan.

Results

Body weight (−2.9% vs. −1.4%), body mass index (BMI) (−3.1% vs. −2.1%), fat-free mass (−2.7% vs. −1.4%), and hydration status were decreased in both males and females after the Ramadan fasting (p < 0.05). REEs (kcal/d) of the participants were 1708.1 ± 262.50 kcal/d and 1596.5 ± 302.27 kcal/d at baseline and post-Ramadan, respectively (6.5%) (p < 0.05). This decrease in REE (kcal/d) in females was greater than that in males (−8.1% vs. −4.6%). However, no statistically significant difference was found in sleep duration (h), physical activity levels, dietary energy and nutrient intakes, and blood pressures (mm Hg) of both genders compared to baseline (p > 0.05).

Conclusion

Intermittent circadian fasting may lead to a decreased energy expenditure and a change in fat-free mass in healthy individuals, and this effect is interpreted as gender-dependent.

Self-Care by Muslim Women during Ramadan Fasting to Protect Nutritional and Cardiovascular Health

The practice of Ramadan involves a series of changes in lifestyle, mainly in eating habits. The research aim of this study is to determine the prevalence of overweight-obesity, the degree of compliance with dietary recommendations and the effects of religious fasting on cardiovascular health among a population of Muslim women living in Melilla, a Spanish city in North Africa. A follow-up cohort study was conducted on 62 healthy adult women (33.6 ± 12.7 years). Anthropometric and body composition parameters were obtained using bioimpedance and dietary records. All of the participants were overweight or obese, especially due to the non-compliance with dietary recommendations; however, more than 60% considered their weight was appropriate or even low. By the end of Ramadan, the women's body mass index and fat component values had fallen significantly (p < 0.001), but this loss was later recovered. Dietary records revealed an excessive consumption of lipids and sodium, and the presence of a high waist-to-hip ratio. All of these factors are related to cardiovascular risk. In conclusion, promoting nutritional health and encouraging year-round self-care among adult Muslim women is necessary in order to ensure healthy fasting during Ramadan.

Impact of COVID-19 on Children and Young Adults With Type 2 Diabetes: A Narrative Review With Emphasis on the Potential of Intermittent Fasting as a Preventive Strategy

Background: The world is still struggling to control the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The level of uncertainty regarding the virus is still significantly high. The virus behaves differently in children and young adults. Most children and adolescents are either asymptomatic or have mild symptoms. They generally have a very good prognosis. However, it is not well-known whether children and young adults with type 2 diabetes are at risk of getting a severe infection of COVID-19. Many Muslim children with type 2 diabetes have been performing dawn to dusk fasting during the month of Ramadan, before and during the COVID-19 pandemic, and the impact of this on their health has not been well investigated. Previous studies in adults have suggested that intermittent fasting may be beneficial in different ways including reversal of type 2 diabetes and prevention of COVID-19 infection. Objective: The primary aim of this narrative review is to summarise the impacts of the COVID-19 pandemic on children and young adults with type 2 diabetes, and to identify the knowledge gaps in the literature. It also explores the potential of intermittent fasting in reversing the pathogenesis of diabetes and highlighting how this approach could prevent these patients from developing chronic complications. Methods: This narrative review has been produced by examining several databases, including Google Scholar, Research Gate, PubMed, Cochrane Library, MEDLINE (EBSCO), and Web of Science. The most common search terms used were "COVID-19 AND Children", "SARS-CoV-2 AND/OR Children", "COVID-19 AND Diabetes" "COVID-19 Epidemiology", "COVID-19 AND Ramadan fasting", "COVID-19 and Intermittent fasting." All the resources used are either peer-reviewed articles/reports and/or official websites of various media, governmental and educational organisations. Results: Having reviewed the currently limited evidence, it has been found that the incidence of COVID-19 among children with type 2 diabetes seems to be not much different from children without diabetes. However, these patients are still vulnerable to any infection. Several studies have reported that prevention programmes such as intermittent fasting are effective to protect these groups of patients from developing any complications. Moreover, observing Ramadan fasting as a type of intermittent fasting could be beneficial for some children with established diabetes, prediabetes and people at risk. Conclusion: Children and young adults with type 2 diabetes are not at risk of severe COVID-19 infection as the case in adults with diabetes. More research is needed to identify the impact of COVID-19 and to investigate the efficacy and safety of intermittent fasting, including Ramadan fasting, among these age groups. Implementing these cost-effective programmes may have a great impact in minimising the incidence of diabetes. Moreover, this could be effective particularly at prediabetes stage by preventing these people from going onto develop type 2 diabetes and taking medications for the rest of their life and protecting people from complications linked to disease and infection.

The Effects of Intermittent Fasting on Brain and Cognitive Function

The importance of diet and the gut-brain axis for brain health and cognitive function is increasingly acknowledged. Dietary interventions are tested for their potential to prevent and/or treat brain disorders. Intermittent fasting (IF), the abstinence or strong limitation of calories for 12 to 48 h, alternated with periods of regular food intake, has shown promising results on neurobiological health in animal models. In this review article, we discuss the potential benefits of IF on cognitive function and the possible effects on the prevention and progress of brain-related disorders in animals and humans. We do so by summarizing the effects of IF which through metabolic, cellular, and circadian mechanisms lead to anatomical and functional changes in the brain. Our review shows that there is no clear evidence of a positive short-term effect of IF on cognition in healthy subjects. Clinical studies show benefits of IF for epilepsy, Alzheimer’s disease, and multiple sclerosis on disease symptoms and progress. Findings from animal studies show mechanisms by which Parkinson’s disease, ischemic stroke, autism spectrum disorder, and mood and anxiety disorders could benefit from IF. Future research should disentangle whether positive effects of IF hold true regardless of age or the presence of obesity. Moreover, variations in fasting patterns, total caloric intake, and intake of specific nutrients may be relevant components of IF success. Longitudinal studies and randomized clinical trials (RCTs) will provide a window into the long-term effects of IF on the development and progress of brain-related diseases.

Associations between Fasting Duration, Timing of First and Last Meal, and Cardiometabolic Endpoints in the National Health and Nutrition Examination Survey

Background: Research indicates potential cardiometabolic benefits of energy consumption earlier in the day. This study examined the association between fasting duration, timing of first and last meals, and cardiometabolic endpoints using data from the National Health and Nutrition Examination Survey (NHANES). Methods: Cross-sectional data from NHANES (2005–2016) were utilized. Diet was obtained from one to two 24-h dietary recalls to characterize nighttime fasting duration and timing of first and last meal. Blood samples were obtained for characterization of C-reactive protein (CRP); glycosylated hemoglobin (HbA1c %); insulin; glucose; and high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol. Survey design procedures for adjusted linear and logistic regression were performed. Results: Every one-hour increase in nighttime fasting duration was associated with a significantly higher insulin and CRP, and lower HDL. Every one-hour increase in timing of the last meal of the day was statistically significantly associated with higher HbA1c and lower LDL. Every one-hour increase in first mealtime was associated with higher CRP (β = 0.044, p = 0.0106), insulin (β = 0.429, p < 0.01), and glucose (β = 0.662, p < 0.01), and lower HDL (β = −0.377, p < 0.01). Conclusion: In this large public health dataset, evidence for the beneficial effect of starting energy consumption earlier in the day on cardiometabolic endpoints was observed.

Intermittent Energy Restriction, Weight Loss and Cardiometabolic Risk: A Critical Appraisal of Evidence in Humans

Dietary patterns with intermittent energy restriction (IER) have been proposed as an attractive alternative to continuous energy restriction (CER) for the management of obesity and its associated comorbidities. The most widely studied regimens of IER comprise energy restriction on two days per week (5:2), alternate-day energy restriction by 60-70% (ADF), and timely restriction of energy intake during a specific time window within the day (TRF; time-restricted feeding). Although there is some evidence to suggest that IER can exert beneficial effects on human cardiometabolic health, yet is apparently not superior compared to CER, there are still some critical issues/questions that warrant further investigation: (i) high-quality robust scientific evidence regarding the long-term effects of IER (safety, efficacy, compliance) is limited since the vast majority of intervention studies had a duration of less than 6 months; (ii) whether the positive effects of IER are independent of or actually mediated by weight loss remains elusive; (iii) it remains unknown whether IER protocols are a safe recommendation for the general population; (iv) data concerning the impact of IER on ectopic fat stores, fat-free mass, insulin resistance and metabolic flexibility are inconclusive; (v) the cost-effectiveness of IER dietary regimens has not been adequately addressed; (vi) direct head-to-head studies comparing different IER patterns with variable macronutrient composition in terms of safety and efficacy are scarce; and (vii) evidence is limited with regard to the efficacy of IER in specific populations, including males, the elderly and patients with morbid obesity and diabetes mellitus. Until more solid evidence is available, individualization and critical perspective are definitely warranted to determine which patients might benefit the most from an IER intervention, depending on their personality traits and most importantly comorbid health conditions.

Beneficial Effects of Early Time-Restricted Feeding on Metabolic Diseases: Importance of Aligning Food Habits with the Circadian Clock

The importance of metabolic health is a major societal concern due to the increasing prevalence of metabolic diseases such as obesity, diabetes, and various cardiovascular diseases. The circadian clock is clearly implicated in the development of these metabolic diseases. Indeed, it regulates physiological processes by hormone modulation, thus helping the body to perform them at the ideal time of day. Since the industrial revolution, the actions and rhythms of everyday life have been modified and are characterized by changes in sleep pattern, work schedules, and eating habits. These modifications have in turn lead to night shift, social jetlag, late-night eating, and meal skipping, a group of customs that causes circadian rhythm disruption and leads to an increase in metabolic risks. Intermittent fasting, especially the time-restricted eating, proposes a solution: restraining the feeding window from 6 to 10 h per day to match it with the circadian clock. This approach seems to improve metabolic health markers and could be a therapeutic solution to fight against metabolic diseases. This review summarizes the importance of matching life habits with circadian rhythms for metabolic health and assesses the advantages and limits of the application of time-restricted fasting with the objective of treating and preventing metabolic diseases.

Food Expenditure and Food Consumption before and during Ramadan in Moroccan Households

Fasting in the month of Ramadan is a religious, cultural, and social ritual for Muslims. The benefits it is supposed to provide to people who practice it are often impaired by unhealthy lifestyles including diet. The present research aimed to study risky eating behaviors and the variation in food expenditure of the Moroccan population during Ramadan. This study was conducted in 2018 in 340 households in urban and rural localities in the Rabat-Salé-Kenitra region of Morocco. Information on eating habits was collected by a nutritional survey using the method of dietary history; household food expenditure and sociodemographic characteristics were collected by a questionnaire. The average age of the population is 40 ± 14 years; the majority (40%) has a middle standard of living, and the average food expenditure increased by 50% during Ramadan. The food survey showed a significant increase in energy intake (p < 0.001), carbohydrate intake (p < 0.001), sucrose intake (p=0.02), sodium intake (p < 0.001), and calcium intake (p < 0.001) and a significant decrease in protein intake (p < 0.001) and lipid intake (p < 0.001), with no significant change in saturated fatty acid intake (p=0.86) during Ramadan. These results show that some dietary behaviors adopted during Ramadan could promote the development or worsening of overweight and chronic diseases. These data reveal the importance of nutritional education adapted to this sacred month.

Association between Time Restricted Feeding and Cognitive Status in Older Italian Adults

Background: Due to the increased life expectancy, the prevalence of aging-related health conditions, such as cognitive impairment, dementia and Alzheimer’s disease is increasing. Among the modifiable risk factors, dietary factors have proved to be of primary importance in preserving and improving mental health and cognitive status in older adults, possibly through the modulation of adult neurogenesis, neuronal plasticity and brain signaling. Feeding/fasting timing manipulation has emerged as an innovative strategy to counteract and treat cognitive decline. The aim of this study was to investigate the association between the timing of the feeding period and cognitive status in a cross-sectional cohort of adults living in the Mediterranean area. Methods: Demographic and dietary characteristics of 883 adults living in Southern Italy (Sicily) were analyzed. Food frequency questionnaires were used to calculate the time window between the first and the last meal of an average day. Participants with an eating time window duration of more than 10 h were then identified, as well as those with eating time restricted to less than 10 h (TRF). Results: After adjusting for potential confounding factors, individuals adherent to TRF were less likely to have cognitive impairment, compared to those with no eating time restrictions [odds ratio (OR) = 0.28; 95% confidence intervals (CI): 0.07–0.90]; a similar association was found for individuals having breakfast (OR = 0.37, 95% CI: 0.16–0.89), but not for those having dinner. Conclusions: The results of this study reveal that time restricted eating may be positively associated with cognitive status, and thus exert plausible effects on brain health.

Self-Coping Strategies Among Jordanian Athletes During Ramadan Fasting: A Questionnaire Proposal

: This study aims to categorize the adaptation strategies of Muslim athletes who fast during Ramadan and proposes a self-coping strategy questionnaire as a complementary assessment tool. A total of 109 Jordanian Muslim athletes (mean age 20.0 ± 8.5 years) were surveyed by completing a self-coping questionnaire designed to classify an individual athlete’s level of adaptation. This study was conducted during the month of Ramadan 2019 and developed based on the training, nutritional, psychological, self-control, and recovery dimensions. Seventy percent of athletes found that they developed good or very good coping mechanisms. Coping strategies vary from one dimension to another, but in general, athletes often had a positive perceived coping. Athletes expressed that they are shifting the training hours with a preference for quality training rather than quantity and associated with a longer rest time. In addition, they were in favor of food hygiene associated with a strategy of sharing meals and providing water. The majority (59%) of the athletes said they were psychologically prepared for the potential effects of fasting. This research shows that athletes develop self-adjusting strategies to counter the effects of fasting. The questionnaire on the self-coping strategies provides important and precise information on the level of coping achieved by the athletes.

Effects of Time-Restricted Feeding during Ramadan on Dietary Intake, Body Composition and Metabolic Outcomes

Ramadan fasting is a form of time-restricted feeding which combines a fast and feast period daily for a duration of one month every year. During Ramadan, Muslims abstain from food and drink consumption from dawn till sunset and this change in the meal schedule and frequency results in significant changes to the composition of the diet, such as energy and nutrient intake. These changes in dietary habits and their corresponding effects on cardiometabolic disease risk are compiled in this review. Ramadan fasting shows limited benefits to body composition via reductions in body mass in both healthy and obese individuals, although the results are often found to be transient and heterogeneous. There is, however, a more consistent improvement in blood lipid profile during Ramadan fasting, which often lasts beyond the Ramadan period. The results for glucose homeostasis, on the contrary, are more conflicting and inconclusive. The heterogeneity in the findings from the various studies can be generally attributed to cultural variations in dietary habits, differences in the duration of fasting due to seasonal/climatic differences at various geographical locations, age, gender and socioeconomic status, as well as other health and lifestyle factors of the various study populations.

Ramadan Intermittent Fasting Affects Adipokines and Leptin/Adiponectin Ratio in Type 2 Diabetes Mellitus and Their First-Degree Relatives

Background

In view of the association of Ramadan intermittent fasting with profound changes in lifestyle both in nondiabetic and diabetic patients, the aim of this study was to investigate the effect of Ramadan fasting on adiponectin, leptin and leptin to adiponectin ratio (LAR), growth hormone (GH), human-sensitive C-reactive protein (hs-CRP), and diabetic and metabolic syndrome factors in patients with Type 2 Diabetes Mellitus (Type 2 DM), their first-degree relatives (FDRs), and healthy controls.

Methods

This cohort study involved 98 Yemeni male subjects aged 30-70 years old: 30 Type 2 DM, 37 FDRs of Type 2 diabetic patients, and 31 healthy control subjects. Subjects' body mass index (BMI), waist circumference (WC), and blood pressure (BP) were measured, and venous blood samples were collected twice: the first samples were collected a couple of days prior to Ramadan fasting (baseline) and the second samples after 3 weeks of fasting.

Results

Ramadan fasting did not affect BMI, WC, and BP in Type 2 DM and their FDRs with respect to the baseline levels prior to Ramadan, whereas triglyceride and cholesterol were borderline significantly decreased in Type 2 DM with no effect in FDRs. Fasting blood glucose was not affected in Type 2 DM but was significantly increased in FDRs and control groups, whereas glycated haemoglobin (HbA1c) was slightly decreased in Type 2 DM, FDRs, and healthy controls. C-peptide, insulin, and insulin resistance (HOMA-IR) were significantly increased in Type 2 DM and FDRs, with no effect in the control group, whereas β-cell function (HOMA-β) was significantly decreased in FDRs and controls with no change in Type 2 DM. Ramadan fasting significantly decreased GH in both FDRs and control groups, and significantly increased hs-CRP in the control with no effect in Type 2 DM and FDRs. Adiponectin was significantly decreased, and leptin and LAR were significantly increased in Type 2 DM, FDRs, and control groups.

Conclusion

Ramadan intermittent fasting decreased adiponectin and increased leptin, LAR, insulin, and insulin resistance in both Type 2 DM and FDRs as well as decreased GH in both FDRs and healthy controls and increased hs-CRP in healthy controls. Moreover, Ramadan intermittent fasting neither worsens a patient's glycemic parameters nor improves it, with the exception of a slight improvement in HbA1c in Type 2 DM, FDRs, and healthy controls.

Bromocriptine mesylate improves glucose tolerance and disposal in a high-fat-fed canine model

Bromocriptine mesylate treatment was examined in dogs fed a high fat diet (HFD) for 8 wk. After 4 wk on HFD, daily bromocriptine (Bromo; n = 6) or vehicle (CTR; n = 5) injections were administered. Oral glucose tolerance tests were performed before beginning HFD (OGTT1), 4 wk after HFD began (Bromo only), and after 7.5 wk on HFD (OGTT3). After 8 wk on HFD, clamp studies were performed, with infusion of somatostatin and intraportal replacement of insulin (4× basal) and glucagon (basal). From 0 to 90 min (P1), glucose was infused via peripheral vein to double the hepatic glucose load; and from 90 to 180 min (P2), glucose was infused via the hepatic portal vein at 4 mg·kg^-1·min^-1, with the HGL maintained at 2× basal. Bromo decreased the OGTT glucose ΔAUC_0-30 and ΔAUC_0-120 by 62 and 27%, respectively, P < 0.05 for both) without significantly altering the insulin response. Bromo dogs exhibited enhanced net hepatic glucose uptake (NHGU) compared with CTR (~33 and 21% greater, P1 and P2, respectively, P < 0.05). Nonhepatic glucose uptake (non-HGU) was increased ~38% in Bromo in P2 (P < 0.05). Bromo vs. CTR had higher (P < 0.05) rates of glucose infusion (36 and 30%) and non-HGU (~40 and 27%) than CTR during P1 and P2, respectively. In Bromo vs. CTR, hepatic 18:0/16:0 and 16:1/16:0 ratios tended to be elevated in triglycerides and were higher (P < 0.05) in phospholipids, consistent with a beneficial effect of bromocriptine on liver fat accumulation. Thus, bromocriptine treatment improved glucose disposal in a glucose-intolerant model, enhancing both NHGU and non-HGU.

A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on glucometabolic markers in healthy subjects

AIM

Studies on the effect of Ramadan diurnal intermittent fasting (RDIF) on glucometabolic markers have yielded conflicting results. We conducted ameta-analysis to estimate the effect size for changes in glucometabolic markers in healthy, non-athletic Muslims during Ramadan, and to assess the effect of variable covariates using meta-regression.

METHODS

CINAHL, Cochrane, EBSCOhost, EMBASE, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus, and Web of Science databases were searched from date of inceptionto January 2020. The glucometabolic markers analyzed were: fasting glucose (FG), insulin, insulin resistance (HOMA-IR), leptin, and adiponectin.

RESULTS

We identified seventy-two studies (3134 participants in total) that were conducted in 22 countries between 1982 and 2020. RDIF-induced effect sizes for the glucometabolic markers were: FG (no. of studies K = 61, number of subjects N = 2743, Hedges'g = -0.102, 95% CI: -0.194, -0.01); serum insulin (K = 16, N = 648, Hedges'g = 0.030 95% CI: -0.165, 0.226); HOMA-IR (K = 10, N = 349, Hedges'g = -0.012, 95% CI: -0.274, 0.250); leptin (K = 13, N = 442, Hedges'g = -0.010, 95% CI: -0.243, 0.223); and adiponectin (K = 11, N = 511, Hedges'g = 0.034, 95% CI: -0.227, 0.296).

CONCLUSION

RDIF imposes no adverse metabolic impacts, and might help in improving some glucometabolic markers in healthy subjects.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of intermittent fasting and energy-restricted diets on lipid profile: A systematic review and meta-analysis

OBJECTIVES

To the best of our knowledge, no systematic review and meta-analysis has evaluated the cholesterol-lowering effects of intermittent fasting (IF) and energy-restricted diets (ERD) compared with control groups. The aim of this review and meta-analysis was to summarize the effects of controlled clinical trials examining the influence of IF and ERD on lipid profiles.

METHODS

A systematic review of four independent databases (PubMed/Medline, Scopus, Web of Science and Google Scholar) was performed to identify clinical trials reporting the effects of IF or ERD, relative to non-diet controls, on lipid profiles in humans. A random-effects model, employing the method of DerSimonian and Laird, was used to evaluate effect sizes, and results were expressed as weighted mean difference (WMD) and 95% confidence intervals (CIs). Heterogeneity between studies was calculated using Higgins I², with values ≥50% considered to represent high heterogeneity. Subgroup analyses were performed to examine the influence of intervention type, baseline lipid concentrations, degree of energy deficit, sex, health status, and intervention duration.

RESULTS

For the outcomes of low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triacylglycerols (TG), there were 34, 33, 35, and 33 studies meeting all inclusion criteria, respectively. Overall, results from the random-effects model indicated that IF and ERD interventions resulted significant changes in TC (WMD, -6.93 mg/dL; 95% CI, -10.18 to -3.67; P < 0.001; I² = 78.2%), LDL-C (WMD, -6.16 mg/dL; 95% CI, -8.42 to -3.90; P ˂ 0.001; I² = 52%), and TG concentrations (WMD, -6.46 mg/dL; 95% CI, -10.64 to -2.27; P = 0.002; I² = 61%). HDL-C concentrations did not change significantly after IF or ERD (WMD, 0.50 mg/dL; 95% CI, -0.69 to 1.70; P = 0.411; I² = 80%). Subgroup analyses indicated potentially differential effects between subgroups for one or more lipid parameters in the majority of analyses.

CONCLUSIONS

Relative to a non-diet control, IF and ERD are effective for the improvement of circulating TC, LDL-C, and TG concentrations, but have no meaningful effects on HDL-C concentration. These effects are influenced by several factors that may inform clinical practice and future research. The present results suggest that these dietary practices are a means of enhancing the lipid profile in humans.

Effects of time-restricted feeding on body weight and metabolism. A systematic review and meta-analysis

Restriction in meal timing has emerged as a promising dietary approach for the management of obesity and dysmetabolic diseases. The present systematic review and meta-analysis summarized the most recent evidence on the effect of time-restricted feeding (TRF) on weight-loss and cardiometabolic variables in comparison with unrestricted-time regimens. Studies involving TRF regimen were systematically searched up to January 2019. Effect size was expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). A total of 11 studies, 5 randomized controlled trials and 6 observational, were included. All selected studies had a control group without time restriction; hours of fasting ranged from 12-h until 20-h and study duration from 4 to 8-weeks. Most studies involved the Ramadan fasting. TRF determined a greater weight-loss than control regimens (11 studies, n = 485 subjects) (WMD: -1.07 kg, 95%CI: -1.74 to -0.40; p = 0.002; I² = 56.2%), unrelated to study design. The subgroup analysis showed an inverse association between TRF and fat free mass in observational studies (WMD: -1.33 kg, 95%CI: -2.55 to -0.11; p = 0.03; I² = 0%). An overall significant reduction in fasting glucose concentrations was observed with TRF regimens (7 studies, n = 363 subjects) (WMD: -1.71 mg/dL, 95%CI: -3.20 to -0.21; p = 0.03; I² = 0%), above all in trials (WMD:-2.45 mg/dL, 95%CI: -4.72 to -0.17; p = 0.03; I² = 0%). No between-group differences in the other variables were found. TRF regimens achieved a superior effect in promoting weight-loss and reducing fasting glucose compared to approaches with unrestricted time in meal consumption. However, long-term and well-designed trials are needed to draw definitive conclusions.

Impact of Ramadan diurnal intermittent fasting on the metabolic syndrome components in healthy, non-athletic Muslim people aged over 15 years: a systematic review and meta-analysis

Studies on the impact of Ramadan diurnal intermittent fasting (RDIF) on the metabolic syndrome (MetS) components among healthy Muslims observing Ramadan month have yielded contradictory results. This comprehensive meta-analysis aimed to obtain a more stable estimate of the effect size of fasting during Ramadan on the MetS components, examine variability among studies, assess the generalisability of reported results and perform subgroup analyses for associated factors. We searched the CINAHL, Cochrane, EBSCOhost, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus and Web of Science databases for relevant studies published from 1950 to March 2019. The MetS components analysed were: waist circumference (WC), systolic blood pressure (SBP), fasting plasma/serum glucose (FG), TAG, and HDL-cholesterol. We identified eighty-five studies (4326 participants in total) that were conducted in twenty-three countries between 1982 and 2019. RDIF-induced effect sizes for the MetS components were: small reductions in WC (no. of studies K = 24, N 1557, Hedges' g = -0·312, 95 % CI -0·387, -0·236), SBP (K = 22, N 1172, Hedges' g = -0·239, 95 % CI -0·372, -0·106), FG (K = 51, N 2318, Hedges' g = -0·101, 95 % CI -0·260, 0·004) and TAG (K = 63, N 2862, Hedges' g = -0·088, 95 % CI -0·171, -0·004) and a small increase in HDL-cholesterol (K = 57, N 2771, Hedges' g = 0·150, 95 % CI 0·064, 0·236). We concluded that among healthy people, RDIF shows small improvement in the five MetS components: WC, SBP, TAG, FG and HDL.