A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on body weight in healthy subjects aged 16 years and above

The impact of intermittent fasting during Ramadan on psychomotor and cognitive skills in adolescent athletes

Introduction

Intermittent fasting (IF) represents a dietary intervention similar to caloric restriction, characterized by the strategic limitation of food consumption. Among the diverse array of practices for IF, Ramadan IF (RIF), a religious observance in Islam, mandates that healthy adult Muslims abstain from both food and drinks during daylight hours. In sports, researchers have extensively studied IF effects on health, including sleep and physical performance, but its impact on cognitive functions during RIF remains understudied. Therefore, this study was conducted to evaluate the influence of RIF on psychomotor and cognitive performance among young female athletes.

Methods

To achieve this purpose, a cohort of 23 female handball players, aged 17.2 ± 0.5 years, participated in a series of six testing sessions: one conducted prior to Ramadan (R0), and others during the first (R1), second (R2), third (R3), and fourth (R4) weeks of Ramadan, followed by a session in the week after Ramadan (R5). Each session involved assessments using a Simple Reaction Time Test (SRT), Choice Reaction Time Test (CRT), Vigilance Test (VT), and Mental Rotation Test (MRT). Additionally, dietary intake, body composition, and Pittsburgh Sleep Quality Index (PSQI) scores were evaluated during these periods.

Results and discussion

The obtained data illustrated that there was a decrease in SRT, CRT, VT, and MRT performances during R1 in comparison to R0 (all p < .001). This reduction was also observed in R2, R3, R4, and R5. Notably, during the fourth week of Ramadan (R4), these cognitive and psychomotor parameters were significantly lower than during the earlier weeks (R1, R2, R3; all p < .001). Furthermore, a gradual decrease in total PSQI scores, sleep quality, and sleep duration was observed throughout the Ramadan period, reaching the lowest levels during R4. These findings illustrate that RIF has a significantly detrimental impact on neuromuscular and cognitive abilities as well as sleep quality in young female athletes. The study also highlights a fluctuating pattern in cognitive function across the four weeks of Ramadan, with the most pronounced decline observed during the final week of fasting illustrating the importance of conducting similar studies on normal individuals from both genders with larger sample size.

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).

Clinical potential of fasting in type 1 diabetes

Most adults with type 1 diabetes (T1DM) are either overweight or obese. As such, dietary management is recommended as an adjunct to insulin treatment to improve glycemic control and facilitate weight loss in these patients. Time-restricted eating (TRE) is a form of intermittent fasting that offers a simplified approach to treating obesity in T1DM. TRE typically involves restricting eating to 6 to 10 h per day, with water and medications allowed outside the eating window. This review examines the efficacy of TRE and other fasting protocols in improving weight and glycemic control in patients with obesity and T1DM. This review will also evaluate the safety of these regimens and provide advice to clinicians on implementing intermittent fasting in T1DM.

The effect of observing religious or faith-based fasting on cardiovascular disease risk factors: A systematic review and meta-analysis

AIMS

Cardiovascular diseases (CVD) are the leading cause of death worldwide. Fasting is common in many religions and is associated with health benefits. This systematic review to compares the impact of different religious fasting practices, on risk of cardiometabolic diseases.

DATA SYNTHESIS

The search covered five databases following PRISMA guidelines to identify papers published in English from inception to March 2023 (updated January 2024). Inclusion criteria were healthy adults in observational studies, who engaged in religious fasting practices, studies were included where data on matched non-fasting individuals was available. Outcomes were systolic and diastolic blood pressure, body mass index (BMI), triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), and fasting plasma glucose levels. A meta-analysis was conducted, and the review was registered (CRD42022352197). Fourteen studies were met the inclusion criteria with ten studies data being suitable for meta-analysis, reporting on 755 adults participating in fasting practices and 661 non-fasting controls. Religious fasting was associated with a reduction in BMI (-0.40 kg/m2, 95% CI [-0.70, -0.10], p < 0.01). Observance of Ramadan fasting was associated with decreased systolic blood pressure (-3.83  mmHg, 95% CI [-7.44, -0.23], p = 0.04). The observance of Orthodox Christian fasting was associated with a reduction in TC (-0.52 mmoL/l, 95%CI [-0.64, -0.39], p < 0.01). No difference was found for the other outcomes.

CONCLUSION

This review found religious fasting practices which were associated with a reduction in some biomarkers of cardiometabolic diseases risk. Further research on other fasting practices is needed due to limited data.

Effect of calorie restriction and intermittent fasting on glucose homeostasis, lipid profile, inflammatory, and hormonal markers in patients with polycystic ovary syndrome: a systematic review

Background and objective

Polycystic ovary syndrome (PCOS) is a complex hormonal disorder that leads to ovarian cysts, irregular ovulation, and hormonal swings in women. It is a complex and heterogeneous condition that affects 4 to 20% of women of reproductive age worldwide and relates to reproductive, metabolic, and psychosocial dysfunction. Dietary and lifestyle modifications have been proposed to play a central role in the management of PCOS. This study aimed to provide a comprehensive systemic overview of the existing literature on the effects of intermittent fasting (IF) and calorie restriction (CR) regimens on disease markers of PCOS.

Designs and methods

Several databases, such as CINAHL, Cochrane, EBSCOhost, EMBASE, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus, and Web of Science databases were searched for clinical trials and observational studies examined the effects of IF regimens such as time-restricted eating and Ramadan model of IF (RIF) on glucose homeostasis, lipid profile, inflammatory and hormonal markers in patients with PCOS.

Results

This systematic review solicited three articles, comprising a collective sample size of 75 females diagnosed with PCOS. The studies were published between 2015 to 2023 and were undertaken in three countries: China, Turkey, and Iran. The research articles examined the effects of intervention with IF and CR on PCOS-related parameters such as anthropometric measures and biochemical tests which included enzymes, glycemic control, lipid profile, hormonal, and oxidative stress, and inflammatory markers. The articles yielded mixed results, with two of them showing significant changes across all tested parameters. One of the three studies did not exhibit any significant changes.

Conclusion

Very limited studies examined the relationship between IR and CR with markers of PCOS. Further well-controlled studies need to be undertaken the combined results from the limited studies illustrate the intricate and diverse nature of IF, including the RIF, and its influence on measurements of body composition and biochemical markers related to PCOS.

Circadian alignment of food intake and glycaemic control by time-restricted eating: A systematic review and meta-analysis

Daily rhythms of metabolic function are supported by molecular circadian clock systems that are strongly regulated by feeding and fasting. Intermittent fasting diets have been associated with weight loss and improved metabolism. However, the effects of time-restricted eating (TRE) on glycemic parameters are still under debate. In this review, we aim to systematically analyze the effects of TRE on glycemic parameters. We searched on PubMed, EMBASE, and the Cochrane Library for controlled studies in which subjects followed TRE for at least 4 weeks. 20 studies were included in the qualitative systematic review, and 18 studies (n = 1169 subjects) were included in the meta-analysis. Overall, TRE had no significant effect on fasting glucose (Hedges's g = -0.08; 95% CI:-0.31,0.16; p = 0.52), but it did reduce HbA1c levels (Hedges's g = -0.27; 95% CI: -0.47, -0.06; p = 0.01). TRE significantly reduced fasting insulin (Hedges's g = -0.40; 95% CI: -0.73,-0.08; p = 0.01) and showed a tendency to decrease HOMA-IR (Hedges's g = -0.32; 95% CI:-0.66,0.02; p = 0.06). Interestingly, a cumulative analysis showed that the beneficial effects of TRE regarding glucose levels were less apparent as studies with later TRE windows (lTRE) were being included. Indeed, a subgroup analysis of the early TRE (eTRE) studies revealed that fasting glucose was significantly reduced by eTRE (Hedges's g = -0.38; 95% CI:-0.62, -0.14; p < 0.01). Our meta-analysis suggests that TRE can reduce HbA1c and insulin levels, and that timing of food intake is a crucial factor in the metabolic benefit of TRE, as only eTRE is capable of reducing fasting glucose levels in subjects with overweight or obesity.PROSPERO registration number CRD42023405946.

An umbrella review and meta-analysis of meta-analyses of the impact of Ramadan fasting on the metabolic syndrome components

CONTEXT

Ramadan is a holy month of fasting, spiritual reflection, and worship for Muslims worldwide. However, the Ramadan fast - which involves abstaining from all food and drink, sunrise to sunset for 29 days-30 days annually - may also influence physical health outcomes, especially relating to the risk of metabolic syndrome.

OBJECTIVE

The literature from the top of the pyramid of evidence was gathered and synthesized for this comprehensive umbrella review and meta-analysis of meta-analyses in order to provide an overall conclusion on the impact of Ramadan fasting with regard to metabolic syndrome components.

DATA EXTRACTION

Eleven systematic reviews and meta-analyses were included in the current umbrella review. Nine components, including waist circumference, body weight), high-density lipoprotein, low-density lipoprotein, total cholesterol, triglycerides, systolic blood pressure, diastolic blood pressure), and fasting blood plasma glucose were analyzed.

DATA ANALYSIS

The random-effects meta-analysis results revealed standard mean differences as follows: waist circumference -0.30 (95% confidence interval [CI] -0.33 to -0.27), body weight -0.34 (95% CI -0.39 to -0.29), high-density lipoprotein 0.20 (95% CI 0.10 to 0.30), low-density lipoprotein -0.10 (95% CI -0.13 to -0.07), total cholesterol -0.15 (95% CI -0.21 to -0.09), triglycerides -0.16 (95% CI -0.24 to -0.08), systolic blood pressure -0.20 (95% CI -0.23 to -0.17), diastolic blood pressure -0.20 (95% CI -0.22 to -0.18), fasting blood plasma glucose -0.10 (95% CI -0.12 to -0.08).

CONCLUSION

Ramadan fasting appears to benefit body weight, lipid profile, blood pressure, and fasting blood glucose levels. Therefore, engaging in fasting during Ramadan may contribute to weight reduction, decreased cardiovascular disease risk, improved blood pressure, and enhanced glycemic control. Nevertheless, the methodological quality of the included reviews ranged from low to critically low, necessitating cautious interpretation of conclusions drawn from these data.

SYSTEMATIC REVIEW REGISTRATION

Open Science Framework Identifier: DOI 10.17605/OSF.IO/9WVJZ.

Metabolic changes with intermittent fasting

BACKGROUND

The prevalence of obesity is rising globally and effective strategies to treat obesity are needed. Intermittent fasting, a dietary intervention for weight management, has received growing interest from the general public, as well as healthcare professionals, as a form of lifestyle intervention.

METHODS

We executed a rapid review using PUBMED database to identify systematic reviews that examined the impact of intermittent fasting on metabolic indices, published between 2011 and 2022.

RESULTS

Intermittent fasting leads to weight loss of a similar magnitude to continuous energy restriction. Most of the evidence shows that intermittent fasting leads to greater fat loss as measured by fat mass (kg) or body fat percentage compared to an ad libitum diet, but fat loss attained during intermittent fasting is not significantly different to continuous energy restriction, although recent evidence shows intermittent fasting to be superior. There is mixed evidence for the impact of intermittent fasting on insulin resistance, fasting glucose and lipid profile. Some studies focused on populations of Muslim people, which showed that Ramadan fasting may lead to weight loss and improvement of metabolic parameters during fasting, although the effects are reversed when fasting is finished.

CONCLUSIONS

Intermittent fasting is more effective than an ad libitum dietary intake, and equally or more effective as continuous energy restriction, for weight management. However, there is inconclusive evidence on whether intermittent fasting has a clinically beneficial effect on glucose and lipid metabolism.

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

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

Alterations in anthropometric, inflammatory and mental health parameters during Ramadan intermittent fasting in a group of healthy people: a prospective cohort study

Fasting has been practiced with different time span in different areas of the world and for various reasons. One of the types of fasting regimens is Ramadan intermittent fasting (RIF), which is described as intermittent dry fasting and known as the most commonly practiced form of religious fasting. Different studies have shown its effects on body composition parameters and mental health, fatigue and quality of life (QoL). Elucidating the relationship of RIF on biological parameters would also be of importance to show its mechanism. Therefore, we evaluated several biological mediators related to mental health, such as ß-nerve growth factor (ß-NGF), brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and insulin-like growth factor-1 (IGF-1), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), and matrix-metalloproteinase-9 (MMP-9). This study consisted of fasting (FG; n = 25) and non-fasting group (NFG; n = 25). Four different time points were assessed for FG: one week before (T1), mid (T2), last days (T3), and one week after (T4) RIF. T1 and T3 were the assessment time points for NFG. Biological mediators were determined from serum samples by using Human Magnetic Luminex and enzyme-linked immunosorbent assay. Furthermore, we then performed correlation analyses between biological mediators and our previously published clinical parameters including body composition and mental health parameters at all time points. Significant alterations were shown in FG for ß-NGF (T2vsT3, p < 0.05; T2vsT4, p < 0.05), GDNF (T1vsT4, p < 0.05; T2vsT4, p < 0.05), IL-8 (T2vsT3, p < 0.05; T3vsT4, p < 0.05), TNF-α (T1vsT3, p < 0.05; T1vsT4, p < 0.001; T2vsT4, p < 0.001), and MMP-9 (T1vsT4, p < 0.01). There were no statistically significant differences between FG and NFG in all biological mediators at T1 and T3. Correlation analysis showed that MMP-9 levels had negative correlation with body mass index (BMI) at T3. At T3 BDNF levels had negative correlation with Epworth Sleepiness Scale (ESS) as one of measured QoL parameters. ß-NGF, GDNF, TNF-α, and MMP-9 had positive correlation with some of body composition and mental health parameters. Findings demonstrate that RIF altered different biological mediators could give benefit to health. Its benefit is mediated by the alteration of biological mediators.

Effect of Intermittent Fasting on Cardiometabolic Health in the Chinese Population: A Meta-Analysis of Randomized Controlled Trials

The efficacy of intermittent fasting (IF), as an emerging weight management strategy, in improving cardiometabolic health has been evaluated in various populations, but that among Chinese individuals has not been systematically studied. A comprehensive search on multiple databases was performed to identify eligible randomized controlled trials (RCTs) up to October 2022. The primary outcome was post-intervention weight loss, and secondary outcomes included changes in cardiometabolic indicators. Effect estimates were meta-analyzed using a random-effects model. In total, nine RCTs with 899 Chinese participants were included. Time-restricted eating was the most adopted IF protocol in this study (six out of nine), followed by alternate-day fasting. The IF intervention significantly reduced body weight, body mass index, body fat mass, homeostatic model assessment of insulin resistance, low-density lipoprotein cholesterol, and triglycerides when compared with control groups. However, no statistically significant reductions in waist circumference, total cholesterol, high-density lipoprotein cholesterol, fasting glucose, systolic blood pressure, and diastolic blood pressure were found. To sum up, IF can be a weight management strategy and may improve the cardiometabolic health of Chinese adults, but more long-term trials using different IF strategies are required to generate robust evidence of its efficacy.

Effect of Calorie Restriction and Intermittent Fasting Regimens on Brain-Derived Neurotrophic Factor Levels and Cognitive Function in Humans: A Systematic Review

Background: The potential positive interaction between intermittent fasting (IF) and brain-derived neurotrophic factor (BDNF) on cognitive function has been widely discussed. This systematic review tried to assess the efficacy of interventions with different IF regimens on BDNF levels and their association with cognitive functions in humans. Interventions with different forms of IF such as caloric restriction (CR), alternate-day fasting (ADF), time-restricted eating (TRE), and the Ramadan model of intermittent fasting (RIF) were targeted. Methods: A systematic review was conducted for experimental and observational studies on healthy people and patients with diseases published in EMBASE, Scopus, PubMed, and Google Scholar databases from January 2000 to December 2023. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statements (PRISMA) for writing this review. Results: Sixteen research works conducted on healthy people and patients with metabolic disorders met the inclusion criteria for this systematic review. Five studies showed a significant increase in BDNF after the intervention, while five studies reported a significant decrease in BDNF levels, and the other six studies showed no significant changes in BDNF levels due to IF regimens. Moreover, five studies examined the RIF protocol, of which, three studies showed a significant reduction, while two showed a significant increase in BDNF levels, along with an improvement in cognitive function after RIF. Conclusions: The current findings suggest that IF has varying effects on BDNF levels and cognitive functions in healthy, overweight/obese individuals and patients with metabolic conditions. However, few human studies have shown that IF increases BDNF levels, with controversial results. In humans, IF has yet to be fully investigated in terms of its long-term effect on BDNF and cognitive functions. Large-scale, well-controlled studies with high-quality data are warranted to elucidate the impact of the IF regimens on BDNF levels and cognitive functions.

The impacts of Ramadan fasting for patients with non-alcoholic fatty liver disease (NAFLD): a systematic review

Background

Numerous studies have explored the impacts of Ramadan fasting on Non-alcoholic fatty liver disease (NAFLD). Therefore, the objective of this systematic review was to analyze and summarize all clinical studies regarding the impacts of Ramadan fasting for patients with NAFLD.

Methods

We performed a comprehensive search of the Embase, Cochrane, and PubMed databases from inception to September 1, 2023. All clinical studies concerning the impacts of Ramadan fasting on patients with NAFLD were included.

Results

In total, six studies with 397 NAFLD patients comprising five prospective studies and one retrospective study were included in the systematic review. All six studies were assessed as high-quality. Ramadan fasting may offer potential benefits for patients with NAFLD, including improvements in body weight, body composition, cardiometabolic risk factors, glucose profiles, liver parameters, and inflammation markers.

Conclusion

Ramadan fasting might be an effective dietary intervention for NAFLD. However, the number of studies examining the impacts of Ramadan fasting for patients with NAFLD is relatively limited. Therefore, more high-quality research is needed to further our understanding of the benefits of Ramadan fasting for NAFLD.

Systematic review registration

https://inplasy.com, identifier 202390102.

Ramadan fasting model exerts hepatoprotective, anti-obesity, and anti-hyperlipidemic effects in an experimentally-induced nonalcoholic fatty liver in rats

BACKGROUND

The epidemic of nonalcoholic fatty liver disease (NAFLD) and its metabolic effects present a serious public health concern. We hypothesized that the Ramadan fasting model (RFM), which involves fasting from dawn to dusk for a month, could provide potential therapeutic benefits and mitigate NAFLD. Accordingly, we aimed to validate this hypothesis using obese male rats.

METHODS

Rats were split into two groups (n = 24 per group), and they were given either a standard (S) or high-fat diet (HFD) for 12 weeks. During the last four weeks of the study period, both S- and HFD-fed rats were subdivided into eight groups to assess the effect of RFM with/without training (T) or glucose administration (G) on the lipid profile, liver enzymes, and liver structure (n = 6/group).

RESULTS

The HFD+RFM group exhibited a significantly lower final body weight than that in the HFDC group. Serum cholesterol, low-density lipoprotein, and triglyceride levels were significantly lower in the HFD+RFM, HFD+RFM+T, and HFD+RFM+G groups than those in the HFDC group. Compared with the HFDC group, all groups had improved serum high-density lipoprotein levels. Furthermore, HFD groups subjected to RFM had reduced serum levels of aspartate transaminase and alanine transaminase compared with those of the HFD-fed group. Moreover, the liver histology improved in rats subjected to RFM compared with that of HFD-fed rats, which exhibited macro- and micro-fat droplet accumulation.

CONCLUSION

RFM can induce positive metabolic changes and improve alterations associated with NAFLD, including weight gain, lipid profile, liver enzymes, and hepatic steatosis.

Changes in energy and macronutrient intakes during Ramadan fasting: a systematic review, meta-analysis, and meta-regression

CONTEXT

Ramadan fasting (RF) is associated with various physiological and metabolic changes among fasting Muslims. However, it remains unclear whether these effects are attributable to changes in meal timing or changes in dietary energy and macronutrient intakes. Furthermore, the literature on the associations between RF, meal timing, and energy and macronutrient intakes is inconclusive.

OBJECTIVES

This systematic review aimed to estimate the effect sizes of RF on energy and macronutrient intakes (carbohydrates, protein, fats, dietary fiber, and water) and determine the effect of different moderators on the examined outcomes.

DATA SOURCES

The Cochrane, CINAHL, EMBASE, EBSCOhost, Google Scholar, PubMed/MEDLINE, ProQuest Medical, Scopus, ScienceDirect, and Web of Science databases were searched from inception to January 31, 2022.

DATA EXTRACTION

The studies that assessed energy, carbohydrate, protein, fat, fiber, and water intakes pre- and post-fasting were extracted.

DATA ANALYSIS

Of the 4776 identified studies, 85 relevant studies (n = 4594 participants aged 9-85 y) were selected. The effect sizes for the studied variables were as follows: energy (number of studies [K] = 80, n = 3343 participants; mean difference [MD]: -142.45; 95% confidence interval [CI]: -215.19, -69.71), carbohydrates (K = 75, n = 3111; MD: -23.90; 95% CI: -36.42, -11.38), protein (K = 74, n = 3108; MD: -4.21; 95% CI: -7.34, -1.07), fats (K = 73, n = 3058; MD: -2.03; 95% CI: -5.73, 1.67), fiber (K = 16, n = 1198; MD: 0.47; 95% CI: -1.44, 2.39), and water (K = 17, n = 772; MD: -350.80; 95% CI: -618.09, 83.50). Subgroup analyses showed age significantly moderated the 6 dietary outcomes, and physical activity significantly moderated water intake. There were significant reductions in energy, carbohydrate, and protein intakes during RF.

CONCLUSIONS

The change in meal timing rather than quantitative dietary intake may explain various physiological and health effects associated with RF.

Ramadan intermittent fasting is associated with ameliorated inflammatory markers and improved plasma sphingolipids/ceramides in subjects with obesity: lipidomics analysis

Intermittent fasting (IF) is associated with enormous metabolic alterations that underpin its diverse health effects. Changes in lipid metabolism, particularly ceramides, and other sphingolipids, are among the most notable of these alterations. This study investigated the lipidomic alterations associated with 29-30 days of Ramadan diurnal intermittent fasting (RIF) in metabolically healthy overweight and obese subjects. A prospective cohort of 57 overweight and obese adults (70% males, 38.4 ± 11.2 years), with an age range of 18-58 years was observed prior to and at the conclusion of Ramadan. At both time points, anthropometric, biochemical (lipid profile, glycemic, and inflammatory markers), and dietary intake measurements were taken. Using liquid chromatography-mass spectrometry, a lipidomic analysis of ceramides and other sphingolipids was conducted. Using paired sample t-tests, pre- and post-Ramadan anthropometric, biochemical, and dietary values were compared. RIF was associated with improved levels of lipid profile compartments and inflammatory markers. In addition, RIF was associated with a decrease in plasma sphingosine and sphinganine, which was accompanied by a decrease in sphingosine 1-phosphate and sphinganine 1-phosphate. In addition, RIF was associated with decreased C17, C22, and C24 sphingomyelin, but not C14, C16, C18, C20, and C24:1 sphingomyelin, as well as C20, C22, C24, and C24:1 dihydrosphingomyelin, but not C16 and C18 dihydrosphingomyelin. This study demonstrates that RIF is associated with improvements in plasma sphingosine, sphinganine sphingomyelin, and dihydrosphingomyelin lipid species, as well as improved lipid profile and inflammatory markers, which may confer short-term protection against cardiometabolic problems in patients with overweight/obesity.

Ramadan Fasting and Short-Term Maximal Physical Performance: Searching for Optimal Timing of the Last Meal "Suhoor" in Female Pre-University Handball Players

Aiming to identify the ideal suhoor timing for maintaining optimal physical performance and health indicators during Ramadan intermittent fasting, the present study compares the effects of early vs. late Suhoor on short-term high-intensity physical exercise while controlling the body mass index (BMI) oral temperature (OT), dietary intake, and sleep patterns. In a randomized design, 19 female pre-university handball players (age: 16.8 ± 0.4 y; height: 1.70 ± 0.9 m; and body mass: 61.5 ± 6.9 kg) underwent two test sessions (at 08:00 a.m. and 05:00 p.m.) at four different conditions: ten days prior to Ramadan (R - 10), the final ten days of Ramadan (R) including both Early Suhoor R(ES) and Late Suhoor R(LS) conditions, and the ten days immediately following Ramadan (R + 10). A recovery period of at least 48 h has been set between successive test sessions at each period. Outcome measures included the Countermovement Jumps Test (CMJ), Modified Agility t-Test (MATT), Repeated Sprint Ability (RSA), and Rating of Perceived Exertion (RPE). The Pittsburgh Sleep Quality Index (PSQI), OT, BMI, and daily diary intake were assessed across the three periods. The total scores of PSQI decreased significantly during R and R + 10 compared to R - 10. When performed in the afternoon, CMJ, MATT, and RSA performance decreased significantly at R(ES) and R(LS) conditions compared to R - 10. However, these performances decreased only after R(ES) when performed in the morning. Furthermore, performances were lower during R(ES) compared to R(LS) in the afternoon for all tests and the morning for MATT and RSA tests. These findings support prior research showing a deterioration of physical performance during Ramadan fasting and indicate a more pronounced impact following early Suhoor condition. Therefore, consuming a late suhoor, closer to pre-dawn time, could be suggested as an effective strategy to minimize physical performance decline during short-term high-intensity exercise.

Alteration in body water compartments following intermittent fasting in Ramadan

Concerning the health outcomes of intermittent fasting in Ramadan, loss of fat-free mass (FFM) and changes in the content of body water are of paramount importance. In this study, we aimed to assess the concomitant alterations in body water compartment and composition following Ramadan fasting in healthy individuals. We conducted an open-label cohort with longitudinal follow-up, involving 73 healthy medical staff who planned to fast for at least 20 consecutive days during Ramadan. The primary outcomes of the cohort were changes in parameters related to body composition and water content, which were measured using bioelectrical impedance analysis by InBody S10 (InBody, Seoul, South Korea). Based on the results, the participants' weight decreased significantly by approximately 1,030 g after the fasting period (p < 0.001). There was a significant reduction in the fat mass of an average 828 g (p < 0.001), which accounted for more than 80% of the weight loss. The decline in FFM was not significant (190 g; p = 0.234). The amount of total body water (TBW) and extracellular water (ECW) did not change, while intracellular water (ICW) decreased significantly by about 160 mL (p = 0.027). A strong correlation was observed between the reduction of phase angle and the increase in ECW/TBW ratio (R = -0.71, p < 0.001). Overall, our findings revealed a minimal amount of weight loss after Ramadan fasting, which was mainly due to the loss of fat mass. The parallel decrease in ICW and phase angle indicated impaired cell membrane integrity, with subsequent movement of water from the intracellular to the extracellular compartment.

Changes in dietary and lifestyle behaviors and mental stress among medical students upon Ramadan diurnal intermittent fasting: a prospective cohort study from Taif/Saudi Arabia

BACKGROUND

Intermittent fasting (IF) is a popular dietary plan for weight loss. In fact, fasting is a common practice in different religions such as Buddhism, Hinduism, Judaism, Christianity, and Islam. During the month of Ramadan, more than 1.5 billion Muslims worldwide fast from dawn to sunset. Ramadan diurnal intermittent fasting (RDIF) has health benefits, including a reduction in cardiovascular disease (CVD) risk and an improvement in mood. However, little is known about the effects of RDIF on lifestyle behaviors, such as regular exercise, consuming healthy diet, and avoiding harmful substances, as well as mental stress, and academic performance in high school and university students.

METHODS

In this prospective cohort study, two self-reported questionnaires were sent one week before and during the last week of Ramadan (April 2022; Ramadan 1443 in Hijri Islamic Calendar) to assess changes in lifestyle, perceived stress, and academic achievement of medical students at Taif University in Taif city, Saudi Arabia. Healthy lifestyle components data were collected to calculate healthy lifestyle scores, including body mass index, physical activity, adherence to a Mediterranean diet, smoking status, and sleep duration.

RESULTS

RDIF was associated with a healthier lifestyle in both female and male participants (pre-RDIF mean score: 2.42 vs post-RDIF mean score: 2.74; statistical power = 0.99; P-value < 0.05). They were more active and adherent to the Mediterranean diet during RDIF. Additionally, the post-RDIF smoking rate declined by 53.4%. Male participants showed higher perceived stress scores during RDIF (pre-RDIF mean score: 19.52 vs post-RDIF mean score: 22.05; P-value < 0.01). No changes in academic performance were observed upon RDIF.

CONCLUSION

Medical students show healthier dietary and lifestyle behaviors and their academic performance is not affected during RDIF. However, perceived stress is higher among male students.

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.

Sex as a biological determinant in anthropometric, biochemical, and dietary changes during Ramadan intermittent fasting in healthy people: A systematic review

AIMS

Observing Ramadan intermittent fasting (RIF) is associated with different behavioral, dietary, and health-related outcomes among healthy and unwell people. Sex is a major biological determinant that affects various health outcomes and impacts the effectiveness of dietary and lifestyle modifications. This systematic review aimed to identify differences in health-related outcomes following the practice of RIF by the sex of study participants.

METHODS

A systematic search was conducted across several databases to qualitatively identify studies focused on dietary, anthropometric, and biochemical outcomes associated with RIF in females and males.

RESULTS

Of 3870 retrieved studies, sex-based differences were reported in 29 studies that included 3167 healthy people (females n = 1558, 49.2%). Most differences between males and females were reported both before and during RIF. Sex differences were examined for 69 outcomes following RIF and included dietary factors (17 outcomes), anthropometrics (13 outcomes), and biochemical factors (39 outcomes), with the latter including metabolic, hormonal, regulatory, inflammatory, and nutrition-related biochemical markers.

CONCLUSIONS

Sex-based differences were observed in the examined dietary, anthropometric, and biochemical outcomes associated with the observance of RIF. More attention needs to be directed toward including both sexes in studies focused on the impact of observing RIF and differentiating outcomes based on sex.

Examination of sleep in relation to dietary and lifestyle behaviors during Ramadan: A multi-national study using structural equation modeling among 24,500 adults amid COVID-19

Background

Of around 2 billion Muslims worldwide, approximately 1.5 billion observe Ramadan fasting (RF) month. Those that observe RF have diverse cultural, ethnic, social, and economic backgrounds and are distributed over a wide geographical area. Sleep is known to be significantly altered during the month of Ramadan, which has a profound impact on human health. Moreover, sleep is closely connected to dietary and lifestyle behaviors.

Methods

This cross-sectional study collected data using a structured, self-administered electronic questionnaire that was translated into 13 languages and disseminated to Muslim populations across 27 countries. The questionnaire assessed dietary and lifestyle factors as independent variables, and three sleep parameters (quality, duration, and disturbance) as dependent variables. We performed structural equation modeling (SEM) to examine how dietary and lifestyle factors affected these sleep parameters.

Results

In total, 24,541 adults were enrolled in this study. SEM analysis revealed that during RF, optimum sleep duration (7-9 h) was significantly associated with sufficient physical activity (PA) and consuming plant-based proteins. In addition, smoking was significantly associated with greater sleep disturbance and lower sleep quality. Participants that consumed vegetables, fruits, dates, and plant-based proteins reported better sleep quality. Infrequent consumption of delivered food and infrequent screen time were also associated with better sleep quality. Conflicting results were found regarding the impact of dining at home versus dining out on the three sleep parameters.

Conclusion

Increasing the intake of fruits, vegetables, and plant-based proteins are important factors that could help improve healthy sleep for those observing RF. In addition, regular PA and avoiding smoking may contribute to improving sleep during RF.

Effects of Ramadan Fasting on Glycaemic Control Among Patients with Type 2 Diabetes: Systematic Review and Meta-analysis of Observational Studies

INTRODUCTION

The prevalence of type 2 diabetes (T2D) is increasing around the world. Although Muslims with a physical illness are exempted from fasting during the month of Ramadan, a great number still choose to fast, often without medical consultations. The aim of this systematic review and meta-analysis was to investigate the impact of observing Ramadan fasting (RF) on glycaemic control in patients with T2D.

METHODS

The Web of Science, Scopus, EBSCOhost, CINAHL, ScienceDirect, Cochrane Library, ProQuest Central and Europe PubMed Central (Medline) databases were searched for relevant studies published between January 2000 and December 2021. Observational studies that examined the changes in body weight (BW) and glucose parameters (glycosylated haemoglobin [HbA1c] and fasting blood glucose [FBG]), before and after RF among different age groups with T2D were included in the systemic review and meta-analysis. Effect sizes for the tested outcomes were calculated as weighted mean difference (WMD), with their confidence intervals (CI). Quality assessment was examined using the National Heart, Lung, and Blood Institute (NHLBI) tool.

RESULTS

Of the 1592 identified records, 12 studies conducted in Middle Eastern and Asian countries were eligible and included in the quantitative analyses. The quality of the retrieved studies was evaluated and found to range between fair (83%) and good (17%). These 12 studies included 5554 participants of whom 54% were males and 46% were females. Our pooled analysis demonstrated that HbA1c and FBG levels significantly decreased after RF when compared to the pre-fasting levels (WMD = 0.55 mg/dl, 95% CI 0.33-0.77, P < 0.00001, Ι² = 93% and WMD = 12.42, CI 6.46-18.38, P < 0.0001, Ι² = 81%, respectively). However, the difference in BW in fasting patients after RF versus the pre-fasting stage was non-significant. Although, young patients with T2D were enrolled in the 12 selected studies, we did not find any studies that solely focussed on this group.

CONCLUSION

The impact of RF on adult patients with T2D is associated with favorable outcomes. However, future studies should evaluate data from young adults separately. In addition, it is essential to identify the effects of the number of fasting days (level of exposure), diet, level of physical activity and sleeping pattern on optimal glycaemic control. This information could be utilized by medical professionals as a non-pharmacological therapeutic method for management of diabetes in patients who are willing to practice fasting during Ramadan and other months of the year.

STUDY REGISTRATION

PROSPERO: CRD42022314752.

The impact of Ramadan intermittent fasting on anthropometric measurements and body composition: Evidence from LORANS study and a meta-analysis

Background

Although the effect of Ramadan intermittent fasting (RIF) on anthropometry and body composition has been questioned, none of the previous studies tried to explain the reported changes in these parameters. Also, systematic reviews that investigated the topic were limited to healthy individuals or a specific disease group.

Methods

The London Ramadan Study (LORANS) is an observational study on health effects of RIF. We measured weight, waist circumference (WC), hip circumference (HC), body mass index (BMI), waist-to-hip ratio (WHR), basal metabolic rate (BMR), fat percentage (FP), free-fat mass (FFM), extremities predicted muscle mass, total body water (TBW), trunk FM, trunk FFM and trunk predicted muscle mass before and immediately after Ramadan. Using mixed-effects regression models, we investigated the effect of RIF with adjustment for potential confounders. We also conducted a meta-analysis of the results of LORANS with other studies that investigated the effect of RIF on anthropometry and body composition. The review protocol is registered with PROSPERO registry (CRD42020186532).

Results

We recruited 146 participants (Mean ± SD age = 43.3 ± 15 years). Immediately after Ramadan, compared with before Ramadan, the mean difference was-1.6 kg (P<0.01) in weight,-1.95cm (P<0.01) in WC,-2.86cm (P <0.01) in HC, -0.60 kg/m2 (P < 0.01) in BMI and -1.24 kg (P < 0.01) in FM. In the systematic review and meta-analysis, after screening 2,150 titles and abstracts, 66 studies comprising 7,611 participants were included. In the general population, RIF was followed by a reduction of 1.12 Kg in body weight (-1.89- -0.36, I2 = 0), 0.74 kg/m2 reduction in BMI (-0.96- -0.53, I2 = 0), 1.54cm reduction in WC (-2.37- -0.71, I2 = 0) and 1.76cm reduction in HC (-2.69- -0.83, I2 = 0). The effect of fasting on anthropometric and body composition parameters starts to manifest in the second week of Ramadan and starts to diminish 3 weeks after Ramadan.

Conclusion

RIF is associated with a reduction in body weight, BMI, WC, HC, FM, FP and TBW. Most of these reductions are partially attributed to reduced FM and TBW. The reductions in these parameters appear to reverse after Ramadan.

Ramadan diurnal intermittent fasting is associated with significant plasma metabolomics changes in subjects with overweight and obesity: A prospective cohort study

Introduction

During the holy month of Ramadan, adult healthy Muslims are mandated to abstain from dawn to sunset, with free eating at night hours that may extend up to 12 h. The current work was designed to investigate the metabolomics changes incurred upon the observance of Ramadan diurnal intermittent fasting (RDIF).

Methods

Twenty-five metabolically healthy participants with overweight and obesity (7 females and 18 males, with a mean age of 39.48 ± 10.0 years) were recruited for the study and were followed before and at the end of RDIF month. Dietary, anthropometric, biochemical, and physical activity assessments were performed before and at the end of the fasting month. The metabolomic assay was performed using liquid chromatography-mass spectrometry for the two-time points.

Results and discussion

Metabolomics assay revealed a significant reduction in a few metabolites. The analysis revealed that 27 metabolites differed significantly (P < 0.05) between pre-and post-RDIF. Among the differentially abundant metabolites, 23 showed a decrease with fasting, these included several amino acids such as aspartame, tryptophan, phenylalanine, histidine, and other metabolites including valeric acid, and cortisol. On the other hand, only four metabolites showed increased levels after RDIF including traumatic acid, 2-pyrrolidinone, PC[18:1(9Z)/18:1(9Z)], and L-sorbose. The MetaboAnalyst^® platform reported that the top enriched metabolic pathways included: (1) histidine metabolism; (2) folate biosynthesis (3) phenylalanine, tyrosine, and tryptophan biosynthesis; (4) aminoacyltRNA biosynthesis; (5) caffeine metabolism; (6) vitamin B₆ metabolism; and several other pathways relating to lipid metabolisms such as arachidonic acid metabolism, glycerophospholipid metabolism, and linoleic acid metabolism. In conclusion, RDIF entails significant changes in various metabolic pathways that reflect different dietary and lifestyle behaviors practiced during the fasting month.

Dietary Intake and Body Composition During Ramadan in Athletes: A Systematic Review and Meta-Analysis With Meta-Regression

The aim of this research was to evaluate the effect of Ramadan observance on dietary intake and body composition in adult athletes. This was a systematic review and meta-analysis. Data sources used were PubMed, Web of Science, Scopus, and Taylor and Francis. Eligibility criteria for selecting studies were as follows: single-group, pre-/post-Ramadan, with or without control group, conducted in athletes aged ≥19 years training at least twice a week, and published in any language before August 25, 2021. Studies assessing dietary intake and/or body composition were deemed eligible. The methodological quality of studies was assessed using QualSyst. Nine studies evaluated dietary intake; 4 of these were rated as strong quality and the remaining as moderate. Of the 17 selected studies evaluating body composition, 7 were of strong quality and the remaining 10 were rated as moderate. Compared to pre-Ramadan, energy (number of studies, K = 7; number of participants, N = 78; g = -0.781; 95% confidence interval [CI], -1.416 to -0.145; p = 0.016), carbohydrate (K = 5; N = 50; g = -1.643; 95% CI, -2.949 to -0.336; p = 0.014), and water (K = 4; N = 39; g = -1.081; 95% CI, -1.371 to -0.790; p = 0.000) intakes decreased during Ramadan. However, fat (K = 5; N = 50; g = -0.472; 95% CI, -1.085 to 0.140; p = 0.131) and protein (K = 5; N = 60; g = -0.574; 95% CI, -1.213 to -0.066; p = 0.079) intakes remained unchanged. Compared to pre-Ramadan, body mass (K = 16; N = 131; g = -0.262; 95% CI, -0.427 to -0.097; p = 0.002) and body fat percentage (K = 8; N = 81; g = -0.197; 95% CI, -0.355 to -0.040; p = 0.014) decreased in the fourth week of Ramadan. Lean body mass did not change during Ramadan (K = 4; N = 45; g = -0.047; 95% CI, -0.257 to 0.162; p = 0.658). Carbohydrate and total water intake decreased with the observance of Ramadan, but fat and protein intake were unchanged. Continued training of athletes during Ramadan was associated with a decreased body mass and body fat percentage, but not lean body mass, toward the end of the fasting month. Key pointsRamadan fasting decreases body mass and body fat percentage of athletes, but not lean body mass.Longer durations of fasting could provoke more pronounced decrements in body mass.Carbohydrate and total water intake decreased during Ramadan in athletes.Future studies, with greater methodological rigor, are required to better discern changes in dietary intake and body composition during Ramadan. Supplemental data for this article is available online at https://doi.org/10.1080/07315724.2021.2000902 .

Religious fasting and its impacts on individual, public, and planetary health: Fasting as a "religious health asset" for a healthier, more equitable, and sustainable society

Religious fasting is practiced by people of all faiths, including Christianity, Islam, Buddhism, Jainism, as well as Hinduism, Judaism, and Taoism. Individual/clinical, public, global, and planetary health has traditionally been studied as separate entities. Nevertheless, religious fasting, in conjunction with other religious health assets, can provide several opportunities, ranging from the individual to the population, environmental, and planetary levels, by facilitating and supporting societal transformations and changes, such as the adoption of healthier, more equitable, and sustainable lifestyles, therein preserving the Earth's systems and addressing major interconnected, cascading, and compound challenges. In this review, we will summarize the most recent evidence on the effects of religious fasting, particularly Orthodox and Ramadan Islamic fasting, on human and public health. Further, we will explore the potential effects of religious fasting on tackling current environmental issues, with a special focus on nutrition/food restriction and planetary health. Finally, specific recommendations, particularly around dietary intake during the fasting rituals, will be provided to ensure a sustainable healthy planet.

Nigerian Muslim's Perceptions of Changes in Diet, Weight, and Health Status during Ramadan: A Nationwide Cross-Sectional Study

The Islamic month of Ramadan is marked by fasting, when Muslims refrain from eating and drinking from dawn to sunset, which has an impact on their dietary habits. The study aimed to assess Nigerian Muslims' dietary modifications during Ramadan and their related changes in body weight and health status. A web-based cross-sectional study was conducted among Nigerian adult Muslims. The survey assessed sociodemographic, dietary habits, eating behaviors, food choices, perceived weight changes, and health status. The logistic regression model was used to assess the predictors of weight change and perceived health status. There were 770 participants, 62.9% of whom were women, ranging in age from 18 to 60 years with a mean age of 27.7 ± 6.4 years. Fruits, palm dates, homemade foods, milk products, and vegetables were more frequently consumed. There were fewer energy drinks, pastries, salty snacks, and carbonated or sugared drinks consumed during Ramadan than before. Over half (54.6%, 95% CI: 51.0-58.9%) of the respondents lost weight during Ramadan, 37.0% (95% CI: 17.4-38.6%) maintained their weight and 8.4% (95% CI: 6.6-10.6%) gained weight during the month. Nearly all (97.3%, 95% CI: 95.8-98.3%) reported having good health during Ramadan, and 2.7% (95% CI: 1.7-4.1%) reported having a poorer health state during Ramadan. There was a significant weight loss and healthy dietary change associated with Ramadan fasting in Nigeria. Public health measures must be in place to impart such positive health behaviors so that such healthy habits continue throughout the year.

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 the 5:2 intermittent fasting diet on non-alcoholic fatty liver disease: A randomized controlled trial

Background and aims

Dietary regimens are crucial in the management of non-alcoholic fatty liver disease (NAFLD). The effects of intermittent fasting (IF) have gained attention in this regard, but further research is warranted. Thus, we aimed to ascertain the overall effects of the 5:2 IF diet (5 days a week of normal food intake and 2 consecutive fasting days) in patients with NAFLD compared to a control group (usual diet).

Methods and results

A 12-week randomized controlled trial was performed to evaluate the effects of the 5:2 IF diet on anthropometric indices, body composition, liver indices, serum lipids, glucose metabolism, and inflammatory markers in patients with NAFLD. The IF group (n = 21) decreased body weight (86.65 ± 12.57–82.94 ± 11.60 kg), body mass index (30.42 ± 2.27–29.13 ± 1.95 kg/m²), waist circumference (103.52 ± 6.42–100.52 ± 5.64 cm), fat mass (26.64 ± 5.43–23.85 ± 5.85 kg), fibrosis (6.97 ± 1.94–5.58 ± 1.07 kPa), steatosis scores/CAP (313.09 ± 25.45–289.95 ± 22.36 dB/m), alanine aminotransferase (41.42 ± 20.98–28.38 ± 15.21 U/L), aspartate aminotransferase (34.19 ± 10.88–25.95 ± 7.26 U/L), triglycerides (171.23 ± 39.88–128.04 ± 34.88 mg/dl), high-sensitivity C-reactive protein (2.95 ± 0.62 −2.40 ± 0.64 mg/L), and cytokeratin-18 (1.32 ± 0.06–1.19 ± 0.05 ng/ml) values compared to the baseline and the end of the control group (n = 23)—p ≤ 0.05 were considered as significant. However, the intervention did not change the levels of high-density lipoprotein cholesterol, total cholesterol, low-density lipoprotein cholesterol, fasting blood sugar, insulin, HOMA-IR, and total antioxidant capacity.

Conclusion

Adhering to the 5:2 IF diet can reduce weight loss and related parameters (fat mass and anthropometric indicators of obesity), as well as hepatic steatosis, liver enzymes, triglycerides, and inflammatory biomarkers in patients with NAFLD.

Assessment of water consumption during Ramadan intermittent fasting: Result from Indonesian cross-sectional study

During Ramadan fasting, people are likely to consume water and beverages lower than recommended intake due to the limited time. However, it is necessary to achieve the recommended daily water intake to maintain the hydration status, as well as productivity during fasting. Unfortunately, there is a lack of data on drinking patterns during Ramadan. This study aims to investigate water and beverage intake and drinking patterns to help achieve water requirements during Ramadan among Indonesian adults. This is a cross-sectional study conducted during the Ramadan period from April to May 2021 (Ramadan 1442 Hijri). We used a self-administered questionnaire on drinking habits during Ramadan and utilized a 7-day fluid record (Liq.In 7) to assess water and beverage intake among participants who were managed through online procedure. There were 380 participants from five universities across Indonesia who completed the questionnaire accordingly and then analyzed it. The result shows that total water and beverage intake during Ramadan among participants was below the recommendation [1,670 (1,326–2,034) ml/day]. Among the type of beverages, water is the highest level of consumption [1,262 (983–1,666) ml/day] then followed by sugar-sweetened beverages [200 (91–350) ml/day]. We found a significant difference in water and beverages consumption between time of iftar [474 (375–590) ml/day], nighttime [574 (414–810) ml/day], and suhoor [560 (423–711) ml/day]. From this study, we found that during Ramadan the most common drinking pattern is 2-4-2, but a drinking pattern of 4-2-2 glasses (sequence of four glasses at iftar, two glasses at nighttime, two glasses at suhoor) had a significantly higher chance to adhere with the recommendation of fluid intake compared to other patterns. Therefore, based on this research on water and beverage intake, it is necessary and important to make improvements among Indonesian adults during Ramadan, and the drinking pattern of 4-2-2 glasses may help to achieve the recommended daily water consumption.

Haptoglobin polymorphism modulates cardiometabolic impacts of four consecutive weeks, dawn to sunset Ramadan intermittent fasting among subjects with overweight/obesity

AIMS

Haptoglobin (Hp) is a multifaceted marker of inflammation, and mediates the interplay between obesity, inflammation, and cardiometabolic dysfunction. However, the role of the Hp phenotype in modulating intermittent fasting (IF)-induced cardiometabolic changes remains to be elucidated.

METHODS

Hp phenotype was determined for the study subjects. Cardiometabolic markers were assessed before and at the end of four consecutive weeks, dawn to sunset IF.

RESULTS

A total of 114 subjects (75 males and 39 females, 38.7 ± 11.7 years, body mass index (BMI) of 30.41 ± 5.09 kg/m²) were recruited. Hp2-2 (n = 55, 48.2 %) and Hp2-1 (n = 53, 46.5 %) were the predominant phenotypes. Significant reductions were observed in serum Hp, IL-6, TNF-α, triglycerides (TG), total cholesterol (TC), LDL, BMI, and fat mass (FM), while a significant elevation was observed in serum CD163, HDL, and IL-10 at the end of the IF month for the whole population. Based on the Hp polymorphism, significant decreases in Hp, BMI, FM, TG, LDL, and TNF-α, with significant increases in HDL and CD163 levels were observed among subjects with Hp2-2 and Hp2-1 phenotypes. A more pronounced reduction in FM was reported in subjects with Hp2-2 in comparison with Hp2-1.

CONCLUSION

Hp gene polymorphism modulates IF-induced changes in cardiometabolic markers.

CLINICAL TRIAL REGISTRATION NUMBER

ISRCTN18205186; https://trialsearch.who.int/?TrialID=ISRCTN18205186.

Bibliometric overview of Ramadan fasting studies during 2010-2021

BACKGROUND AND AIMS

To quantify the bibliometric parameters of Ramadan fasting literature from 2010 to 2021.

MATERIALS AND METHODS

Scopus was searched for all articles related to Ramadan fasting or Islamic fasting from the beginning of 2010 to the end of 2021. Only original articles and reviews were included and their bibliometric and scientometric parameters were determined using Excel, Graph Pad Prism, VOSviewer, and Sci2 tool software.

RESULTS

Finally 1276 articles, including 1109 original articles and 167 reviews, were included. These articles had 14263 citations and an H-index of 48. Based on the number of publications, top institute, top journal, top country, and top authors were University of Sfax (n = 48 articles), Diabetes Research and Clinical Practice (n = 69), the United States (n = 144), and Chtourou H & Hassanein M (n = 38), respectively. Also, Diabetes Research and Clinical Practice had a strong bibliographic coupling with other journals. The recent bursting words were adrenal insufficiency and COVID-19. The most co-occurred topics were the effect of Ramadan fasting on diabetic patients, pregnant women, and glycemic state and body composition of diabetic patients.

CONCLUSION

This study provided a comprehensive bibliometric overview of Ramadan fasting literature from 2010 to 2021. The temporal change in the number of publications and other analyses on the literature of 2019, 2020 and 2021 showed that substantial increasing publications with new emerging subjects had become of interest to many researchers during the last three years.

Sex as a Biological Factor in the Changes in Disease Patients During Ramadan Intermittent Fasting: A Systematic Review

Background

During Ramadan, many patients with diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy choose to fast even against their doctor's advice. The impact of this intermittent fasting on health and disease could be different in men and women. The aim of this study was to determine the effect of sex as a factor in diseases outcomes of patients who opt to fast during Ramadan.

Main Body

The articles included in this study reported data on six diseases: diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy. A systematic search was performed on PubMed and Scopus for observational and clinical studies mentioning Ramadan, diabetes, renal, cardiovascular, gastrointestinal diseases, headaches, and epilepsy in both men and women. Data was extracted by two independent reviewers using a standardized data-collection form. From 381 original articles, 38 studies were selected, including 25,023 patients of which 44.4% were women. Sex-based differences were reported by 18 studies for several variables such as body mass index, blood glucose, the frequency of hypoglycemia, renal colic, mortality, thrombosis, and gastrointestinal diseases in patients fasting during Ramadan. Most of the differences between men and women were reported both in the baseline period before Ramadan and during Ramadan. Indeed, during the period outside Ramadan, the frequency of renal colic, cardiovascular, gastrointestinal diseases, were higher in men; while body mass index, Thrombosis, and headache were higher in women. In the remaining 21 studies, it was reported that the sex factor was not associated with the effect of Ramadan fasting in the frequency and other outcomes of these diseases.

Conclusion

Currently, small attention is paid to sex as a determinant factor in patients while fasting during Ramadan. There appeared to be differences in the frequency and incidence of diseases in men and women during Ramadan. Closer attention to sex differences regarding the frequency and the progression of the diseases during fasting may help to improve patient care, especially to benefit those patients willing to fast during Ramadan.

Exergaming During Ramadan Intermittent Fasting Improve Body Composition as Well as Physiological and Psychological Responses to Physical Exercise in Adolescents With Obesity

The effects of exergaming on biochemical responses has been investigated; however, no data is available for this effect during Ramadan intermittent fasting (RIF). RIF is a daily fasting characterized by abstaining from eating and drinking from sunrise to sunset for 29–30 days. The purpose of this study was to investigate the effect of exergaming during RIF on body composition, physical performance and hematological parameters in overweight and adolescents with obesity. Twenty-four adolescents with obesity were divided into two groups [control group (CG), n = 12, or cooperative sport exergaming group (EG), n = 12: 45 min per session during five days per week)]. Participants completed a 6-min walking test (6MWT), a squat jump test and a 10 and a 30m sprint tests in four different occasions: before Ramadan (T0), the second week of Ramadan (T1), the fourth week of Ramadan (T2), and after Ramadan (T3). Blood pressure, rating of perceived exertion (RPE), body composition, central obesity index, dietary intake and profile of mood states (POMS) were, also, assessed over the four periods. The results showed that body weight, body mass index and body fat percentage were significantly lower at T2 compared to T0 and T1 in the EG. After RIF, body composition returned to the values recorded before RIF. The POMS score was significantly lower during T2 compared to T0, T1 and T3 in the EG. The vertical jump and the 6MWT distance were significantly higher (i) at T2 compared to T0, T1 and T3 in the EG and (ii) in EG compared to CG at T2. RPE was significantly lower (i) at T2 compared to T0, T1 and T3 in the EG and (ii) in EG compared to CG at T2. Blood pressure was lower during T2 compared to the other periods in EG. The EG experienced significant decreases in total cholesterol and triglycerides during T2. However, no significant changes between groups and periods was reported for all the other parameters. In conclusion, exergaming during RIF has a positive effect on body composition and physiological and psychological responses in adolescents with obesity.

Effects of Diurnal Ramadan Intermittent Fasting on Cardiometabolic Risk Factors and Sleep Quality in Healthy Turkish Adults

This study aimed to evaluate the effect of diurnal Ramadan fasting on cardiometabolic risk factors (blood glucose, lipid profile, inflammatory cytokines) and sleep quality in healthy Turkish adults. This prospective observational study was conducted with a total of 32 individuals (12 males, 20 females) who were aged between 19-32 years and fasted for 25 or more continuous days in Ankara, Turkey between 1 Ramadan 1442 and 30 Ramadan 1442. Individuals applied fasting for 16 hours in the spring season. Blood samples were taken after at least 8 hours of fasting, anthropometric measurements were taken and sleep quality was assessed using The Pittsburgh Sleep Quality Index (PSQI) at the beginning and the end of Ramadan. There was a significant decrease in body mass index (BMI), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-α) levels during Ramadan fasting (p < .005). There were no changes in lipid profiles and sleep quality. There was a significant increase in fasting blood glucose levels (p < .05); however, this change is within normal limits. There was also a significant relationship between BMI and CRP, IL-6, and TNF-α levels (p < .05). The diurnal Ramadan fasting did not affect lipid profiles and sleep quality in healthy Turkish subjects. However, decreased BMI and inflammatory cytokine levels were observed at the end of Ramadan fasting. More studies are needed to clarify the role of Ramadan fasting in healthy populations.

Effect of Ramadan intermittent fasting on inflammatory markers, disease severity, depression, and quality of life in patients with inflammatory bowel diseases: A prospective cohort study

Background

Intermittent fasting (IF) during the month of Ramadan is part of the religious rituals of Muslims. The effect of intermittent fasting on disease activity in inflammatory bowel diseases (IBD) is still unknown. This is the first study to assess the effect of IF during Ramadan on inflammatory markers in patients diagnosed with IBD. The effects on clinical disease activity, quality of life, and levels of depression were also assessed.

Methods

Patients diagnosed with ulcerative colitis (UC) or Crohn’s disease (CD) who intended to observe Ramadan fasting were recruited. The following were assessed immediately before and at the end of Ramadan: Serum CRP and stool calprotectin, partial Mayo score, Harvey Bradshaw index (HBI), Simple IBD questionnaire (SIBDQ), and Hamilton depression scale questionnaire.

Results

80 patients diagnosed with IBD were recruited (60 UC, 20 CD). Serum CRP and stool calprotectin did not show a significant change before vs after fasting (median CRP 0.53 vs 0.50, P value = 0.27, Calprotectin 163 vs 218 respectively, P value = 0.62). The partial Mayo score showed a significant rise after fasting (median 1 before vs 1 after fasting, mean: 1.79 vs 2.33 respectively, P value = 0.02). Harvey-Bradshaw index did not show a significant change after fasting (median 4 vs 5, P value = 0.4). Multiple linear regression revealed that older age and a higher baseline calprotectin were associated with a higher change in Mayo score after fasting (P value = 0.02 and P value = 0.01, respectively). No significant change was detected in SIBDQ or Hamilton depression scale scores.

Conclusions

In patients diagnosed with UC, IF during Ramadan was associated with worsening of clinical parameters, the effect was more pronounced in older patients and those with higher baseline calprotectin levels. However, IF during Ramadan was not associated with an adverse effect on objective inflammatory markers (CRP and calprotectin).

Ramadan Intermittent Fasting Is Associated with Changes in Circulating Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) in Metabolically Healthy Obese Subjects

Background and Objectives: Dietary modification is the principal approach to the management of hyperlipidemia in adults. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key regulator of plasma cholesterol and a target for novel lipid-lowering pharmacotherapies. This study aimed to explore how circulating levels of PCSK9 changed during Ramadan intermittent fasting in metabolically healthy obese subjects. Materials and Methods: This cross-sectional study used convenience sampling to recruit 55 overweight and obese participants (22 females and 33 males) who observed Ramadan fasting. Body weight and composition, glucoregulatory factors, serum PCSK9 concentration, dietary intake, and physical activity were assessed 1 week before and at the end of Ramadan fasting. Results: The median (interquartile range) age was 35 (22) years, and body mass index was 30.2 (5.4). We found significant (p < 0.05) increases in serum levels of PCSK9, serum insulin, insulin resistance, and leptin at the end of Ramadan compared with pre-fasting levels. Significant (p < 0.05) reductions in body weight, waist circumference, systolic and diastolic blood pressure, total cholesterol, triglycerides, high-density lipoprotein cholesterol, and adiponectin were also observed at the end of Ramadan. Conclusions: Observing Ramadan fasting was associated with increased PCSK9 levels in metabolically healthy obese subjects. The complex relationships between PCSK9 and insulin resistance and dysregulation of adipokine secretion in relation to dietary and lifestyle modifications during Ramadan warrant further research.

Considering intermittent fasting among Saudis: insights into practices

BACKGROUND

There is a dearth of studies on intermittent fasting in Saudi Arabia outside of Ramadan. The aim of this research was to study and describe the practice of intermittent fasting outside of Ramadan among Saudi people.

METHODS

A web-based survey that focused on intermittent fasting practices-specifically the use of intermittent fasting applications, goal setting, and the effects of fasting on an individual's state of health-was administered, collected, and analyzed.

RESULTS

The study revealed that 58% (298/514) of the respondents practiced intermittent fasting for a duration of less than 3 months. The most-practiced pattern of intermittent fasting was a 16/8 fasting pattern (43.8%, 225/514). About 88.3% (454/514) of those who followed intermittent fasting drank fluids while fasting. Additionally, the amount of weight loss after intermittent fasting was less than 2.2 kg for 35% (180/514) of the participants. The primary goal of intermittent fasting for 44.9% (231/514) of the respondents was to lose weight. The majority of the participants (84.6%, 435/514) did not use any fasting applications.

CONCLUSION

The results of the current research on intermittent fasting outside of Ramadan are preliminary and inconclusive. The findings of the present study advance the idea that for some Saudis, the practice of intermittent fasting does not necessarily begin and end with Ramadan; this finding may present a strategic opportunity for Saudi health professionals who are focused on the obesity epidemic and other public health issues in Saudi Arabia. This study sought to help start a discussion on this topic and fill the knowledge gap.

Ramadan Diurnal Intermittent Fasting Is Associated With Attenuated FTO Gene Expression in Subjects With Overweight and Obesity: A Prospective Cohort Study

Aim and Background

A growing body of evidence supports the impact of intermittent fasting (IF) on normalizing body weight and that the interaction between body genes and environmental factors shapes human susceptibility to developing obesity. FTO gene is one of these genes with metabolic effects related to energy metabolism and body fat deposition. This research examined the changes in FTO gene expression upon Ramadan intermittent fasting (RIF) in a group of metabolically healthy subjects with overweight and obesity.

Methods

Sixty-three (63) subjects were recruited, of which 57 (17 males and 40 females, mean age 38.4 ± 11.2 years) subjects with overweight and obesity (BMI = 29.89 ± 5.02 kg/m2were recruited and monitored before and at the end of Ramadan month), and 6 healthy subjects with normal BMI (21.4 ± 2.20 kg/m2) recruited only to standardize the reference for normal levels of FTO gene expression. In the two-time points, anthropometric, biochemical, and dietary assessments were undertaken, and FTO gene expression tests were performed using RNA extracted from the whole blood sample.

Results

In contrast to normal BMI subjects, the relative gene expressions in overweight/obese were significantly decreased at the end of Ramadan (−32.30%, 95% CI–0.052 −0.981) in comparison with the pre-fasting state. Significant reductions were found in body weight, BMI, fat mass, body fat percent, hip circumference, LDL, IL-6, TNF-α (P&lt;0.001), and in waist circumference (P&lt;0.05), whilst HDL and IL-10 significantly increased (P&lt;0.001) at the end of Ramadan in comparison with the pre-fasting levels. Binary logistic regression analysis for genetic expressions showed no significant association between high-energy intake, waist circumference, or obesity and FTO gene expression.

Conclusions

RIF is associated with the downregulation of the FTO gene expression in subjects with obesity, and this may explain, at least in part, its favorable metabolic effects. Hence, RIF presumably may entail a protective impact against body weight gain and its adverse metabolic-related derangements in subjects with obesity.

Diabetes and Ramadan: Practical guidelines 2021

Fasting during Ramadan is one of the five pillars of Islam and is obligatory for all healthy Muslims from the age of puberty. Though individuals with some illness and serious medical conditions, including some people with diabetes, can be exempted from fasting, many will fast anyway. It is of paramount importance that people with diabetes that fast are given the appropriate guidance and receive proper care. The International Diabetes Federation (IDF) and Diabetes and Ramadan (DaR) International Alliance have come together to provide a substantial update to the previous guidelines. This update includes key information on fasting during Ramadan with type 1 diabetes, the management of diabetes in people of elderly ages and pregnant women, the effects of Ramadan on one's mental wellbeing, changes to the risk of macrovascular and microvascular complications, and areas of future research. The IDF-DAR Diabetes and Ramadan Practical Guidelines 2021 seek to improve upon the awareness, knowledge and management of diabetes during Ramadan, and to provide real-world recommendations to health professionals and the people with diabetes who choose to fast.

Effects of Intermittent Fasting on Cardiometabolic Health: An Energy Metabolism Perspective

This review summarizes the effects of different types of intermittent fasting (IF) on human cardiometabolic health, with a focus on energy metabolism. First, we discuss the coordinated metabolic adaptations (energy expenditure, hormonal changes and macronutrient oxidation) occurring during a 72 h fast. We then discuss studies investigating the effects of IF on cardiometabolic health, energy expenditure and substrate oxidation. Finally, we discuss how IF may be optimized by combining it with exercise. In general, IF regimens improve body composition, ectopic fat, and classic cardiometabolic risk factors, as compared to unrestricted eating, especially in metabolically unhealthy participants. However, it is still unclear whether IF provides additional cardiometabolic benefits as compared to continuous daily caloric restriction (CR). Most studies found no additional benefits, yet some preliminary data suggest that IF regimens may provide cardiometabolic benefits in the absence of weight loss. Finally, although IF and continuous daily CR appear to induce similar changes in energy expenditure, IF regimens may differentially affect substrate oxidation, increasing protein and fat oxidation. Future tightly controlled studies are needed to unravel the underlying mechanisms of IF and its role in cardiometabolic health and energy metabolism.

Ramadan fasting and weight change trajectories: Time-varying association of weight during and after Ramadan in low-income and refugee populations

Obesity is a significant driver of the global burden of non-communicable diseases. Fasting is one approach that has been shown to improve health outcomes. However, the effects of Ramadan fasting differ in that the type, frequency, quantity, and time of food consumption vary. This phenomenon requires in-depth evaluation considering that 90% of Muslims (~2 billion people) fast during Ramadan. To address this issue, we evaluated the pattern of weight change during and following Ramadan for a total of 52 weeks. The study was conducted in Amman, Jordan. Between 2012 and 2015, 913 participants were recruited as part of a trial investigating the efficacy of a weight loss intervention among those with or at risk for diabetes. Weight was measured weekly starting at the beginning of Ramadan, and changes were analyzed using discrete and spline models adjusted for age, sex, and trial group. Results show slight weight gain within the first two weeks and weight loss in the subsequent weeks. During the first week of Ramadan, the estimate for a weight reduction was 0·427 kg, (95% CI: -0·007, 0·861), increasing to 1·567 kg, (95% CI: 2·547, 3·527) at week 26. There was clear evidence of gradual weight gain from about 4 to 15 weeks and a drop towards the end of the investigation at week 28 (-0·12kg, 95% CI: -0·89, 0·56). Our results show that weight changes occurred during and after Ramadan. Weight fluctuations may affect health risks, and thus, findings from this study can inform interventions. Public health agencies could leverage this period of dietary change to sustain some of the benefits of fasting. The authors (DEZ, EFD) acknowledge the Mulago Foundation, the Horace W. Goldsmith Foundation, Robert Wood Johnson Foundation, and the World Diabetes Foundation. TRIAL REGISTRATION. Clinicaltrials.gov registry identifier: NCT01596244.

The impact of dawn to sunset fasting on immune system and its clinical significance in Covid-19 pandemic

Dawn to sunset fasting, a type of intermittent fasting commonly practiced in the month of Ramadan, requires fasting from dawn to sunset without food or liquid intake. Dawn and dusk are two transition time zones of the day that play a critical role in the human circadian rhythm. Practicing dawn to sunset fasting requires the alignment of mealtimes and wake-sleep times with the human biological dawn and dusk. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impairs immune cell responses at multiple levels and leads to severe Coronavirus Disease 2019 (COVID-19). It generates high levels of pro-inflammatory cytokines and chemokines, also known as a cytokine storm, leads to mitochondrial dysfunction and generation of excessive amounts of mitochondrial reactive oxygen species, downregulates autophagy to escape detection for unchecked replication, and alters gut microbiome composition. Severe cases of COVID-19 have been associated with several comorbidities that impair immune responses (e.g., obesity, diabetes, malignancy) and blood laboratory abnormalities (e.g., elevated procalcitonin, C-reactive protein, interleukin-6 (IL-6), leukocytosis, lymphopenia). Several studies of dawn to sunset fasting showed anti-inflammatory effect by suppressing several pro-inflammatory cytokines, reducing oxidative stress, inducing a proteome response associated with increased autophagy, remodeling the gut microbiome, and improving the components of metabolic syndrome (e.g., obesity, blood glucose levels, blood pressure, lipids). In conclusion, dawn to sunset fasting has the potential to optimize the immune system function against SARS-CoV-2 during the COVID-19 pandemic as it suppresses chronic inflammation and oxidative stress, improves metabolic profile, and remodels the gut microbiome. This review presents scientific literature related to the effects of dawn to sunset fasting on the immune system. Studies are needed to assess and confirm the potential benefits of dawn to sunset fasting against SARS-CoV-2.

Does observance of Ramadan affect sleep in athletes and physically active individuals? A systematic review and meta-analysis

The purpose of this systematic review and meta-analysis is to provide an accurate description of the effect of Ramadan observance on sleep duration, sleep quality, daily nap duration, and daytime sleepiness in athletes and physically active individuals. Five electronic databases (PubMed, Web of Science, Scopus, Wiley, and Taylor and Francis) were used to search for relevant studies conducted with athletes or physically active individuals during Ramadan, published in any language, and available before May 23, 2021. Studies that included assessments of sleep quantity and/or quality, and/or daytime sleepiness, and/or daily naps in athletes and physically active individuals were included. The methodological quality of the studies was assessed using "QualSyst". Of the 18 papers included in this study (298 participants in total), 14 were of strong quality, two were moderate, and the remaining two were rated as weak. Individuals who continued to train during Ramadan experienced a decrease in sleep duration (number of studies, K = 17, number of participants, N = 289, g = -0.766, 95% confidence interval [CI] -1.199 to -0.333, p = 0.001). Additionally, the global score of the Pittsburgh Sleep Quality Index increased from 4.053 (K = 5, N = 65, 95% CI 3.071-5.034) pre-Ramadan, to 5.346 (95% CI 4.362-6.333) during Ramadan, indicating a decrease in sleep quality. The duration of daytime naps increased during compared to pre-Ramadan (K = 2, N = 31, g = 1.020, 95% CI 0.595-1.445, p = 0.000), whereas Epworth Sleepiness Scale scores remained unchanged during versus pre-Ramadan (K = 3, N = 31, g = 0.190, 95% CI -0.139-0.519, p = 0.257). In conclusion, individuals who continued to train during Ramadan experienced a decrease in sleep duration, impairment of sleep quality, and increase in daytime nap duration, with no change in daytime sleepiness levels.

Ramadan Fasting Improves Body Composition without Exacerbating Depression in Males with Diagnosed Major Depressive Disorders

Background: Ramadan fasting (RF) is a form of intermittent fasting that generally improves body composition and related metabolic profiles. Whether RF exacerbates depressive symptomatology in individuals diagnosed with major depressive disorder (MDD) is undetermined. Methods: 100 men, who lived in Bahrain and were between the ages of 18 and 64 years with an established diagnosis of MDD, participated in this 4-week study. Based on preference, participants were assigned to a fasting group (FG, n = 50) and a non-fasting group (NFG, n = 50). The FG engaged in fasting from 03:40 to 18:10 (dawn and dusk timings). Changes in depressive symptoms, body mass, body composition, and components of metabolic syndrome were measured. Results: There were no significant changes in depressive symptoms within the FG vs. NFG after controlling for baseline covariates: mean difference 0.49 (SE = 0.63), p = 0.43. No adverse effects were reported in either group. The FG experienced significant reductions in body mass, 1.87 kg, p = 0.001; body mass index, 0.69 kg/m², p = 0.001; body fat, 0.87%, p = 0.001; body surface area, 0.03 m², p = 0.001; and lean mass, 0.77 kg, p = 0.001. Conclusions: RF did not negatively affect depressive symptoms and improved body composition, suggesting short-term intermittent fasting may be a safe dietary practice for adult males with MDD.

The effects of Ramadan intermittent fasting on liver function in healthy adults: A systematic review, meta-analysis, and meta-regression

INTRODUCTION

Growing evidence is suggestive that intermittent fasting likely to improve liver function; however, still the evidences are controversial to draw a definitive conclusion. Therefore, we conducted a systematic review and meta-analysis to estimate the effect size for changes in liver function tests (LFT) in healthy people practicing Ramadan diurnal intermittent fasting (RDIF), and to examine the impact of different covariates using subgroup analysis and meta-regression.

METHODS

Scientific databases were searched from date of inception in 1950 to the end of July 2020. The liver function tests searched and analyzed were aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), bilirubin (BLU), L-lactate dehydrogenase (LDH) and prothrombin time (PT).

RESULTS

Twenty studies (601 adult participants in total, aged 18-57 years) conducted in 10 countries between 1987 and 2020 were identified. RDIF-induced effect sizes for the LFT expressed as standardized mean difference (SMD) [95% confidence interval] were: AST (no. of studies K = 16, number of subjects N = 502, SMD = -0.257 [-0.381, -0.133], I² = 42%); ALT (K = 16, N = 502, SMD = -0.105 [-0.282, 0.07], I² = 71%); GGT (K = 2, N = 46, SMD = -0.533 [-0.842, -0.224], I² = 0%); ALP (K = 10, N = 312, SMD = -0.318 [-0.432, -0.204], I² = 0.0%); BLU (K = 10, N = 325, SMD = -0.264 [-0.520, -0.007], I² = 70.1%); LDH (K = 5, N = 145, SMD = -0.041 [-0.380, 0.298], I² = 72%); PT (K = 2, N = 74, SMD = -0.027 [-0.732, 0.678], I² = 87%).

CONCLUSION

RDIF induces significant but small (AST, ALP, BLU) to medium (GGT) positive changes on LFT, and may confer a transient, short-term protection against fatty liver disease in healthy subjects.