Ramadan Fasting in Germany (17-18 h/Day): Effect on Cortisol and Brain-Derived Neurotrophic Factor in Association With Mood and Body Composition Parameters

Distinct biophysiological effects of Ramadan fasting and traditional intermittent fasting on markers of body fat storage. A real-life study

BACKGROUND

Ramadan Intermittent fasting (RIF) exerts beneficial metabolic effects and improves gastrointestinal motility. However, a comparison between RIF and the traditional 16-hours intermittent fasting (16IF), a strategy for weight loss, is lacking.

METHODS

A total of 34 subjects (median age 32.5 years, range 18-63 years; median BMI 24.5 Kg m-1², range 18.6-37.6 Kg m-1²) were assigned to RIF (N = 18) or 16IF (N = 16) for 30 days. We measured variations in anthropometric measures (BMI, waist, and abdominal circumference), serum insulin, glucose, cortisol, non-esterified fatty acid (NEFA), body fat composition (bioelectrical impedance analysis), and the ultrasonographic measurements of liver steatosis (Hepatorenal index, HRI) and thickness of subcutaneous (SAT) and visceral (VAT) fats.

RESULTS

At baseline, BMI, rates of liver steatosis and distribution of normal weight, overweight, and obese subjects were comparable between the two groups. Body weight significantly decreased at the end of fasting in both RIF (-4.2 % vs baseline, P = 0.002) and 16IF (-2.1 % vs baseline, P = 0.002). Waist and abdominal circumferences significantly decreased only in RIF as well as the amount of body fat. In subjects with liver steatosis, SAT and VAT significantly decreased following RIF, but not 16h-IF, as well as the ultrasonographic HRI.

CONCLUSION

Both 16IF and RIF are able, during 1-month, to reduce body weight. However, RIF but not 16IF also generates marked beneficial effects in terms of reduced subcutaneous fat and liver steatosis. Further studies urge to verify the effects of different models of IF in weight-cycling and long-term management of obesity and related dysmetabolic conditions, such as ectopic fat over-storage.

Ramadan fasting in the third trimester of pregnancy and postpartum colostrum cortisol concentrations in Morocco

Breast milk cortisol concentration varies among and within lactating women, but the causes and consequences of variation are not yet fully understood. This study investigated whether maternal fasting from food and water for over 16 h per day during the third trimester of pregnancy was associated with increased concentrations of cortisol in colostrum during the month of Ramadan in a Moroccan sample. Participants were women who gave birth at the public maternity hospital in Rabat, Morocco throughout the month of and month following Ramadan. Participants completed interviews (N = 92), underwent anthropometric assessment (N = 73), and colostrum samples (N = 63) were collected approximately 48-72 h postpartum. Cortisol analysis was completed on a subset of colostrum samples (N = 43). Women were categorized as fasting every day of Ramadan before giving birth (N = 52/92, 57%), fasting some days (N = 29/92, 32%), and not fasting (N = 11/92, 11%). For women who fasted, average fasting duration was 19.5 days (range: 1-29 days), and average time between the last day of fasting and birth was 8.8 days (range: 0-43 days). The number of days of fasting was positively associated with cortisol concentrations in colostrum (p < .009) in a multivariate analysis controlling for maternal anthropometry, hypertension and/or diabetes, and reasons for opting out of fasting. Each day of fasting was associated with a 4.05% increase in colostrum cortisol. Results are consistent with the hypothesis that maternal fasting during the third trimester of pregnancy increases breast milk cortisol and thus alters the hormonal milieu to which the infant is exposed.

Adaptive Effects of Endocrine Hormones on Metabolism of Macronutrients during Fasting and Starvation: A Scoping Review

Food deprivation can occur for different reasons. Fasting (<24 h duration) occurs to meet religious or well-being goals. Starvation (>1-day duration) occurs when there is intentional (hunger strike or treatment of a medical condition) or unintentional (anorexia nervosa, drought, epidemic famine, war, or natural disaster) food deprivation. A scoping review was undertaken using the PubMed database to explore 1805 abstracts and review 88 eligible full-text articles to explore the adaptive relationships that emerge between cortisol, insulin, glucagon, and thyroid hormones on the metabolic pathways of macronutrients in humans during fasting and starvation. The collected data indicate that fasting and starvation prime the human body to increase cortisol levels and decrease the insulin/glucagon ratio and triiodothyronine (T3) levels. During fasting, increased levels of cortisol and a decreased insulin/glucagon ratio enhance glycogenolysis and reduce the peripheral uptake of glucose and glycogenesis, whereas decreased T3 levels potentially reduce glycogenolysis. During starvation, increased levels of cortisol and a decreased insulin/glucagon ratio enhance lipolysis, proteolysis, fatty acid and amino acid oxidation, ketogenesis, and ureagenesis, and decreased T3 levels reduce thermogenesis. We present a potential crosstalk between T3 and the above hormones, including between T3 and leptin, to extend their adaptive roles in the metabolism of endogenous macronutrients during food deprivation.

Impact of Ramadan fasting on serum levels of major endocrinology hormonal and biochemical parameters in healthy non-athlete adults: A systematic review and meta-analyses

BACKGROUND

Ramadan Intermittent Fasting (RIF) has the potential to alter hormonal levels in the body. This study investigates the impact of RIF on hormonal levels among healthy individuals during Ramadan.

METHODS

A systematic review and meta-analysis of previously published studies were conducted, focusing on healthy non-athlete adults. The intervention examined was Ramadan Intermittent Fasting, and the primary outcomes assessed were changes in endocrine hormonal and biochemical parameters. The pooled effect measure was expressed as odds ratio (OR) and 95% confidence interval (CI) using the random-effects model.

RESULTS

A total of 35 original articles were retrieved, with a combined sample size of 1,107 participants eligible for the meta-analysis. No significant relationship was found between pre- and post-Ramadan hormonal levels of T3, T4, TSH, FT3, FT4, Testosterone, LH, FSH, Prolactin, PTH, Calcium, and Phosphorus (P-value<0.05). However, a substantial decrease in morning cortisol levels was observed across the studies (P-value: 0.08, Hedges' g = -2.14, 95% CI: -4.54, 0.27).

CONCLUSIONS

Ramadan Intermittent Fasting results in minimal hormonal changes and is a safe practice for healthy individuals. The fasting regimen appears to disrupt the circadian rhythm, leading to a decrease in morning cortisol levels.

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 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.

Fasting diets: what are the impacts on eating behaviors, sleep, mood, and well-being?

Fasting diets (FDs) have drawn great attention concerning their contribution to health and disease over the last decade. Despite considerable interest in FDs, the effect of fasting diets on eating behaviors, sleep, and mood-essential components of diet satisfaction and mental health- has not been addressed comprehensively. Understanding the critical role that fasting plays in these elements will open up potential treatment avenues that have not yet been explored. The aim of the present paper was to conduct a comprehensive critical review exploring the effects of fasting on eating behaviors, sleep, and mood. There is currently a lack of clarity regarding which fasting option yields the most advantageous effects, and there is also a scarcity of consistent trials that assess the effects of FDs in a comparable manner. Similarly, the effects and/or treatment options for utilizing FDs to modify eating and sleep behaviors and enhance mood are still poorly understood. Further researches aiming at understanding the impacts of various fasting regimes, providing new insights into the gut-brain axis and offering new treatment avenues for those with resistant anxiety and depression, are warranted. Alteration of eating behaviors can have lasting effects on various physiological parameters. The use of fasting cures can underpin ancient knowledge with scientific evidence to form a new approach to the prevention and treatment of problems associated with co-morbidities or challenges pertaining to eating behaviors. Therefore, a thorough examination of the various fasting regimens and how they impact disease patterns is also warranted.

Intermittent Fasting as a Potential Therapeutic Instrument for Major Depression Disorder: A Systematic Review of Clinical and Preclinical Studies

Recent studies have reported positive effects of Intermittent Fasting (IF) on metabolic parameters, cognition, and mood. However, regarding depressive symptoms, the effect of IF is not clear. The purpose of this review was to assess the available evidence on IF interventions for depression in both clinical and preclinical studies. Of the 23 included studies, 15 were performed on humans and 8 on animal models. The studies on rodents suggested that IF acts as a circadian regulator, improving neurotransmitter availability and increasing the levels of neurotrophic factors in the brain. However, the investigations on humans mainly evaluated healthy volunteers and showed a great heterogeneity regarding both the IF regimen studied and the observed effects on mood. Most available clinical trials have specific limitations, such as small sample sizes and uncontrolled designs. A comprehensive systematic review was conducted on five databases, PubMed, Cochrane, the Central Register of Controlled Trials, Web of Science databases, BVS and Scopus, identifying 23 relevant studies up to 6 October 2022. IF has potentially relevant physiological effects for the treatment of mood disorders, but better designed studies and controlled evaluations are needed to evaluate its efficiency in the treatment of major depression.

Perceived changes in the mental well-being among Nigerians due to Ramadan Intermittent Fasting during the COVID-19 pandemic

INTRODUCTION

Muslims fast every year during the month of Ramadan from dawn until dusk. This study examined mental well-being and correlating factors among Nigerian adults who observed Ramadan intermittent fasting (RIF).

METHODS

A validated generalized anxiety disorder-2 and Patient Health Questionnaire-2, the four-item spiritual well-being index, and the Islamic intrinsic religiosity questionnaire were used to collect data about mental well-being (depression, anxiety), spirituality, and intrinsic religiosity through a web-based survey between the May 9, 2021 (27th of Ramadan, 1442) and the June 4, 2021 (29th of Shawwal, 1442). We studied the mental well-being of respondents over a period of 4 weeks before Ramadan (BR) and during the 4 weeks of Ramadan between the April 12, 2021 and the May 12, 2021(DR). Multinomial regression analysis was used to determine the factors associated with depression and anxiety. This research did not receive any grant or funding.

RESULTS

A total of 770 adult Nigerians who observed RIF study were included in this cross-sectional study. When compared to mental well-being BR, observing RIF by Nigerian adult respondents was associated with a significant improvement in their mental well-being. A higher proportion of respondents felt less depressed DR (61.3% vs. 56.5%. < .001). Interest and pleasure in doing things improved DR than BR (p= 0.007) and respondents felt less nervous and anxious (60.7% vs. 57.1%, respectively; p <.001). Mental well-being was independently associated with sociodemographic characteristics, physical activity, and perceived relationships.

CONCLUSIONS

This study found significant improvement in mental well-being DR compared to BR despite the ongoing COVID-19 pandemic. The effect of RIF on mental well-being needs further research with multicentric studies among different sets of ethnic populations.

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.

Improvement in endothelial function in hypertensive patients after Ramadan fasting: effects of cortisol

BACKGROUND

There are studies on the effects of Ramadan fasting (RF), which is one of the intermittent fasting diets, on both hypertension and endothelial function. However, the relationship between possible improvements in endothelial function and blood pressure after RF is not clear. In this study, we aimed to evaluate the effects of RF on blood pressure and endothelial dysfunction in patients with arterial hypertension (HT).

METHODS

: Sixty-four HT patients, aged 45-65, who were followed up in the Cardiology Department of Kayseri City Hospital and fasted during Ramadan between 13 April and 13 May 2021 with their self-consents were enrolled to study. Body mass index (BMI), blood pressure, and flow-mediated dilatation (FMD) were assessed before and after Ramadan. Also, 5 mL venous blood samples were taken between 8:00 and 8:30 a.m. from all participants to assess cortisol, C-reactive protein (CRP), and other laboratory data.

RESULTS

: In patients, FMD values were found to be higher after Ramadan compared to values before the fasting period (p < 0.001). CRPand cortisol levels decreased after fasting, and the decrease in CRP (95% CI for B = -1.685 - -0.334, p = 0.009) and cortisol levels (95% CI for B = -0.392 - 0.092, p = 0.039) were determined as the predictive factors for FMD after RF.

DISCUSSION

Endothelial functions as determined by FMD improved after 30 days of intermittent fasting. The decreased CRP and cortisol levels may contribute to the improvement in FMD after RF.

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.

Importance of Intermittent Fasting Regimens and Selection of Adequate Therapy on Inflammation and Oxidative Stress in SARS-CoV-2 Infection

The unpredictable nature of new variants of coronavirus 2 (SARS-CoV-2)-highly transmissible and some with vaccine-resistance, have led to an increased need for feasible lifestyle modifications as complementary therapies. Systemic inflammation is the common hallmark of communicable diseases like severe coronavirus disease 2019 (COVID-19) and non-communicable chronic diseases (NCDs) such as obesity, cardiovascular diseases (CVD), diabetes mellitus, and cancers, all for which mitigation of severe outcomes is of paramount importance. Dietary quality is associated with NCDs, and intermittent fasting (IF) has been suggested as an effective approach for treatment and prevention of some NCDs, similar to that of caloric restriction. There is a paucity of high-quality data from randomized controlled trials regarding the impact of IF and the intake of specific nutrients on inflammation and post-infection outcomes in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The current review of recent literature was performed to explore the immunomodulatory roles of IF regimens and supplements involving the intake of specific nutrients including vitamins (A, B, C, D, and E), zinc, and nutraceuticals (n-3 polyunsaturated fatty acids, quercetin, and probiotics) on inflammatory and oxidative stress markers, with consideration of how they may be related to SARS-CoV-2.

Ramadan Fasting in Health and Disease in 2021: A Narrative Review

Introduction: The literature on the health aspects of Ramadan fasting (RF) is widely spread in many journals.

Materials and Methods: This is a narrative review of data obtained from the PubMed database (National Library of Medicine, Bethesda, Maryland, United States). We used the search term “Ramadan fasting,” and relevant records were examined. The publications are narrated thematically.

Results: The publications spanned fundamental, clinical, professional, cultural, and advocacy facets. The publications crossed conventional disciplinary lines and geographical locations and appeared in journals with different access systems. The contents are presented under the themes that emerged depending on the retrieved literature. This year basic coverage included changes in physiology and nutrition during Ramadan. However, the clinical issues included a wide range of topics. These included the impact of RF on nonalcoholic fatty liver disease and adjustments needed in endocrine replacement therapy for hypothyroidism and adrenal insufficiency. Coverage also included chronic kidney disease. The impact on maternal health, fetal well-being, and long-term effects of RF exposures were addressed in several studies. Studies in cardiovascular medicine focused on blood pressure and cardiovascular risk factors. Sports medicine and athletes' well-being received somewhat prominent coverage. The impact on renal function, particularly in patients with chronic kidney disease, was investigated by a few authors. Several groups addressed the eyes' structure and function, neurological conditions, especially headache disorders, and hematological and oncological conditions. Finally, the impact of RF on several aspects of mental health and well-being was addressed by various groups.

Conclusions: Health aspects of RF received a sustained academic interest with a broad spectrum in 2021. This narration provides an overview of the year's scholarly health-related literature on various aspects of health and disease. It should help researchers and clinicians catch up quickly with the health concerns during Ramadan.