Effects of intermittent fasting on serum lipid levels, coagulation status and plasma homocysteine levels

Can caloric restriction improve outcomes of elective surgeries?

Energy restriction (ER) is a nutrition method to reduce the amount of energy intake while maintaining adequate nutrition. In clinical medicine, applications of ER have been implicated in longevity, mortality, metabolic, immune, and psychological health. However, there are limited studies showing the clinical benefit of ER within the immediate surgical setting. A specific, clinically oriented summary of the potential applications of ER is needed to optimize surgery outcomes for patients. The purpose of this article is to examine how ER can be used for perioperative optimization to improve outcomes for the patient and surgeon. It will also explore how these outcomes can feasibly fit in with enhanced recovery after surgery protocols and can be used as a method for nutrition optimization in surgery. Despite evidence of caloric restriction improving outcomes in critically ill surgical patients, there is not enough evidence to conclude that ER, perioperatively across noncritically ill cohorts, improves postoperative morbidity and mortality in elective surgeries. Nevertheless, a contemporary account of how ER techniques may have a significant role in reducing risk factors of adverse surgical outcomes in this cohort, for example, by encouraging preoperative weight loss contributing to decreased operating times, is reviewed.

Intermittent fasting and cardiovascular disease: A scoping review of the evidence

Intermittent fasting (IF), characterized by alternating periods of fasting and unrestricted eating, typically within an 8-hour window or less each day, has gained significant attention as a possible dietary approach. While it is recognized for its metabolic advantages, like weight loss and enhanced glucose and insulin sensitivity, its effect on cardiovascular health remains a topic of mixed opinions. Recent findings suggest a potential downside, with reports indicating a concerning association: a 91 % higher risk of cardiovascular disease (CVD) mortality compared to eating spread across a 12- to 16-hour period. Despite this alarming statistic, the evidence cannot establish a causal link. The impact of IF on CVD is still insufficiently understood, with benefits sometimes exaggerated and risks downplayed in popular discourse. This scoping review aims to consolidate the current evidence, addressing unresolved questions about the benefits and risks of IF, particularly its association with CVD risks and mortality. The goal is to provide a balanced perspective on the potential health implications of IF, emphasizing the need for further research to clarify its long-term effects on cardiovascular health.

Ramadan intermittent fasting is associated with improved anticoagulant activity among healthy people: a case-control study

Data on the pathophysiological mechanisms of hemostatic alterations in the thrombotic events that occur during Ramadan intermittent fasting (RIF), particularly in the natural coagulation inhibitors, are very limited. Thus, our objective was to evaluate the effect of RIF on the natural anticoagulants level, antithrombin, protein C, and total and free protein S (PS) in healthy participants. Participants were divided into two groups. Group I consisted of 29 healthy fasting participants whose blood samples were taken after 20 days of fasting. Group II included 40 healthy non-fasting participants whose blood samples were taken 2-4 weeks before the month of Ramadan. Coagulation screening tests including prothrombin time (PT), activated partial thromboplastin time (APTT) and plasma fibrinogen level, natural anticoagulants; antithrombin, protein C, free and total PS and C4 binding protein (C4BP) levels were evaluated in the two groups. High levels of total and free PS without change in antithrombin, protein C, and C4BP levels were noted in the fasting group as compared with non-fasting ones (p < 0.05). PT and APTT showed no difference between the two groups. However, the fibrinogen level was higher in the fasting group. In conclusion, RIF was found to be associated with improved anticoagulant activity in healthy participants, which may provide temporal physiological protection against the development of thrombosis in healthy fasting people.

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.

Glucagon-Like Peptide-1 (GLP-1) during Ramadan: Narrative Review of the Published Literature

Ramadan fasting, a religious practice observed by Muslims worldwide, involves abstaining from eating, drinking, smoking, and using oral medications from dawn to dusk during the ninth lunar month. Studies have demonstrated that fasting during Ramadan has been shown to increase HDL cholesterol, leptin, adiponectin, and insulin sensitivity, as well as lower several hemostatic risk factors for cardiovascular diseases. Additionally, it may result in a drop in blood sugar levels, especially in diabetics who are also on blood sugar-lowering medicine. Hypoglycemia, characterized by low blood sugar levels, could also result from fasting during Ramadan. The GLP-1 (glucagon-like peptide-1) hormone plays a significant role in regulating glucose metabolism and insulin secretion, and Ramadan fasting can affect its production and release in the gut. Research contributes to our understanding of the utilization of GL-1 medications during Ramadan among patients, broadening therapy alternatives and offering insightful information for well-informed decision-making. Therefore, this narrative review aims to explore the current evidence that studies the safety and efficacy of GLP-1 agonists during Ramadan for nondiabetic and diabetic patients to ensure healthy fasting during Ramadan.

Ramadan-specific nutrition education improves cardio-metabolic health and inflammation-a prospective nutrition intervention study from Pakistan

There are recent reports that Ramadan fasting (RF) results in weight gain instead of weight loss. In addition, the data on the efficacy of brief nutrition education on healthy eating practices in Ramadan for better health are scarce. Therefore, a study was conducted to investigate the effects of brief nutrition education before the start of RF on healthy eating practices during RF. For this purpose, a prospective observational study focused on "Dietary Education and Awareness for Ramadan (DEAR)" as an intervention was carried out. The participants (n = 74) were recruited and divided into two groups, i.e., intervention and control groups (n = 37 each). As an intervention, nutrition education lessons were given before and during RF month. The control group did not attend these nutrition education lessons. Data on anthropometrics, dietary intake, and other parameters were collected at three time points: before, in the end, and 4 weeks after RF. Weight was measured in kg; height, waist circumference (WC), and hip circumference (HC) were measured in cm; and body mass index (BMI) was calculated. Waist-to-hip ratio (WHR) was calculated by dividing the waist value by the hip value. Body composition analysis was performed by the body composition analyzer (BF-907). Blood pressure (BP) was measured using a validated automated blood pressure. A 3-5 ml of venous blood was collected, and plasma and serum were separated. Serum and plasma samples were processed for general blood chemistry (blood lipid profile, glucose, and CRP) within 2 h. CRP was determined by the immunoturbidimetry method using an auto-analyzer. An enzyme-linked immunosorbent assay (ELISA) was used to determine cytokine/chemokines. Adherence to nutrition education (intervention) was assessed. The results show that nutrition education has positive effects on overall nutrition. Significant improvement in dietary adherence to dietary advice in the intervention group was noted. Significant BW loss (mean loss: 1.21 kg) in the intervention group was observed. The majority (63.3%) had lost BW ≥ 1.0 kg. Other changes observed as a result of the intervention included improvements in blood glucose, cholesterol, CRP levels, and systolic and diastolic BP. There was a notable shift in pro- and anti-inflammatory cytokine concentrations: IL-7, IL-4, and TGF-α decreased, while IL-2, TNF-α and resistin, IL-1 RA, IL-17 A, and sCD40 increased. In conclusion, RF resulted in a loss in mean BW and an improvement in related blood chemistry and cytokine profiles. Furthermore, nutrition education before RF resulted in better nutrition practices during RF and a desirable healthy BW, blood lipid, and cytokine profiles.

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.

Effects of time-restricted feeding (16/8) combined with a low-sugar diet on the management of non-alcoholic fatty liver disease: A randomized controlled trial

OBJECTIVES

Emerging studies have employed time-restricted feeding (TRF) and a low-sugar diet alone in the management of non-alcoholic fatty liver disease (NAFLD), but their combination has not been tested. The aim of this study was to investigate the effects of TRF combined with a low-sugar diet on NAFLD parameters, cardiometabolic and inflammatory biomarkers, and body composition in patients with NAFLD.

METHODS

A 12-wk randomized controlled trial was performed to compare the effects of TRF (16 h fasting/8 h feeding daily [16/8]) plus a low-sugar diet versus a control diet based on traditional meal distribution in patients with NAFLD. Changes in body composition, anthropometric indices, and liver and cardiometabolic markers were investigated.

RESULTS

TRF 16/8 with a low-sugar diet reduced body fat (26.7 ± 5.4 to 24.2 ± 4.9 kg), body weight (83.8 ± 12.7 to 80.5 ± 12.1 kg), waist circumference (104.59 ± 10.47 to 101.91 ± 7.42 cm), and body mass index (29.1 ± 2.6 to 28 ± 2.7 kg/m²), as well as circulating levels of fasting blood glucose and liver (alanine aminotransferase, 34 ± 13.9 to 21.2 ± 5.4 U/L; aspartate aminotransferase, 26.3 ± 6.2 to 20.50 ± 4 U/L; γ-glutamyl transpeptidase, 33 ± 15 to 23.2 ± 11.1 U/L; fibrosis score, 6.3 ± 1 to 5.2 ± 1.2 kPa; and controlled attenuation parameter, 322.9 ± 34.9 to 270.9 ± 36.2 dB/m), lipids (triacylglycerols, 201.5 ± 35.3 to 133.3 ± 48.7 mg/dL; total cholesterol, 190 ± 36.6 to 157.8 ± 33.6 mg/dL; and low-density lipoprotein cholesterol, 104.6 ± 27.3 to 84 ± 26.3 mg/dL), and inflammatory markers (high-sensitivity C-reactive protein, 3.1 ± 1.1 to 2 ± 0.9 mg/L; and cytokeratin-18, 1.35 ± 0.03 to 1.16 ± 0.03 ng/mL). These results were statistically significant (P < 0.05) compared with the control group.

CONCLUSIONS

TRF plus a low-sugar diet can reduce adiposity and improve liver, lipid, and inflammatory markers in patients with NAFLD.

The effects of fasting diets on nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. There is no confirmed treatment for NAFLD as yet. Recently, fasting regimens and their relationship to NAFLD have drawn a great deal of attention in the literature. We review the current evidence that supports fasting diets as an adjunctive therapeutic strategy for patients with NAFLD and address potential action mechanisms. We reason that the fasting diets might be a promising approach for modulating hepatic steatosis, fibroblast growth factors 19 and 21 signaling, lipophagy, and the metabolic profile.

The Role of Intermittent Fasting in the Management of Nonalcoholic Fatty Liver Disease: A Narrative Review

Intermittent fasting is a non-pharmacological dietary approach to management of obesity and metabolic syndrome, involving periodic intervals of complete or near-complete abstinence from food and energy-containing fluids. This dietary strategy has recently gained significant popularity in mainstream culture and has been shown to induce weight loss in humans, reduce gut and systemic inflammation, and improve gut microbial diversity and dysbiosis (largely in animal models). It has been hypothesized that intermittent fasting could be beneficial in the management of nonalcoholic fatty liver disease, given the condition's association with obesity. This review summarizes protocols, potential mechanisms of action, and evidence for intermittent fasting in nonalcoholic fatty liver disease. It also highlights practical considerations for implementing intermittent fasting in clinical practice. A search of the literature for English-language articles related to intermittent fasting or time-restricted feeding and liver disease was completed in PubMed and Google Scholar. Potential mechanisms of action for effects of intermittent fasting included modulation of circadian rhythm, adipose tissue and adipokines, gut microbiome, and autophagy. Preclinical, epidemiological, and clinical trial data suggested clinical benefits of intermittent fasting on metabolic and inflammatory markers in humans. However, there was a paucity of evidence of its effects in patients with nonalcoholic fatty liver disease. More clinical studies are needed to determine mechanisms of action and to evaluate safety and efficacy of intermittent fasting in this population.

Effects of Prolonged Intermittent Fasting Model on Energy Metabolism and Mitochondrial Functions in Neurons

Background:

Calorie restriction (CR) during daily nutrition has been shown to affect the prognosis of many chronic diseases such as metabolic syndrome, diabetes, and aging. As an alternative nutrition model, prolonged intermittent fasting (PF) in humans is defined by the absence of food for more than 12 h. In our previous human studies, CR and PF models were compared and it was concluded that the two models might have differences in signal transduction mechanisms. We have investigated the effects of these models on neurons at the molecular level in this study.

Methods:

Neurons (SH-SY5Y) were incubated with normal medium (N), calorie-restricted medium (CR), fasting medium (PF), and glucose-free medium (G0) for 16 h. Simultaneously, ketone (beta-hydroxybutyrate; bOHB) was added to other experiment flasks containing the same media. Concentrations of lactate, lactate dehydrogenase (LDH), bOHB, and glucose were measured to demonstrate the changes in the energy metabolism together with the mitochondrial functions of cells. Citrate synthase activity and flow cytometric mitochondrial functions were investigated.

Results:

At the end of incubations, lactate and LDH levels were decreased and mitochondrial activity was increased in all ketone-added groups (P < .01) regardless of the glucose concentration in the environment. In the fasting model, these differences were more prominent.

Conclusion:

Our results demonstrated that neurons use ketones regardless of the amount of glucose, and bOHB-treated cells had positive changes in mitochondrial function. We conclude that the presence of bOHB might reverse neuron damage and that exogenous ketone treatment may be beneficial in the treatment of neurological diseases in the future.

Gut microbiota modulation as a possible mediating mechanism for fasting-induced alleviation of metabolic complications: a systematic review

BACKGROUND

Intermittent fasting has been reported to have positive effects on obesity, diabetes, cardiovascular diseases, hypertension, and several neurodegenerative diseases through different mechanisms such as alteration in the gut microbiota. This systematic review was conducted with the aim of providing an overview of the existing animal and human literature regarding the gut microbiota alterations in various fasting regimens.

METHOD

A systematic literature search was conducted on PubMed, Scopus and Web of Science databases up to May 2021 to find all relevant studies examining the gut microbiota alteration during the fasting. Original researches on animal models or human patients were included in this study.

RESULTS

The search fulfilled 3072 documents from which 31 studies (20 animal and 11 human studies) were included. Upon fasting, abundance of several beneficial bacteria including Lactobacillus and Bifidobacterium shifted significantly. Moreover, some taxa, including Odoribacter which negatively associated with blood pressure bloomed during fasting. Ramadan fasting, as a kind of intermittent fasting, improves health parameters through positive changes in gut microbiota including upregulation of A. muciniphila, B. fragilis, Bacteroides and butyric acid-producing Lachnospiraceae.

CONCLUSION

The findings suggest that different fasting regimens including alternate-day fasting, calorie- and time-restricted fasting programs and Ramadan fasting could promote health maybe through the modulation of gut microbiome. However, further studies are needed to explore properly the connection between gut microbiota and meal frequency and timing.

Impact of Ramadan fasting on disease activity in patients with multiple sclerosis: a multicenter study

BACKGROUND

The safety of Ramadan fasting for Muslim patients suffering from multiple sclerosis (MS) is still a matter of debate. This work aimed to study the clinical course of MS during Ramadan fasting and to clarify the predictors of relapses and symptoms exacerbation.

METHODS

This retrospective study included 153 Muslim patients with MS. Data related to the disease course before Ramadan were obtained from patients' files, whereas data related to the disease activity during Ramadan, were collected from patients over the two months following Ramadan.

RESULTS

Patients with MS who experienced relapses, exacerbation of symptoms and development of new symptoms during Ramadan had a statistically significant longer disease duration compared to those who did not experience (P < 0.001, <0.001, 0.01 respectively). Also, patients who experienced relapses, exacerbation of symptoms and development of new symptoms during Ramadan had a statistically significant higher expanded disability status scale (EDSS) compared to those who did not experience (P <0.001, <0.001,0.01, respectively). The occurrence of relapses, exacerbation of symptoms and development of new symptoms during Ramadan, were significantly higher in patients who experienced relapses in the preceding year compared to those who did not (P= 0.002, 0.002, 0.01, respectively). Binary logistic regression revealed that each score elevation of EDSS increased the odds of relapse during Ramadan by 1.02 (P-value = 0.04). Also, each month's increase in disease duration increased the odds of relapse during Ramadan by 1.87 (P-value = 0.046).

CONCLUSION

High EDSS and long disease duration are independent predictors of relapse during Ramadan.

Impact of Fasting on Cardiovascular Outcomes in Patients With Hypertension

ABSTRACT

Fasting has been frequently practiced for religious or medical purposes worldwide. However, limited literature assesses the impact of different fasting patterns on the physiologic and cardiac-related parameters in patients with hypertension. This review aims to examine the effect of fasting on cardiovascular outcomes in hypertensive patients. Medline, Embase, and Cochrane library were systematically screened until March 2021 for observational prospective cohorts investigating the effect of fasting on cardiovascular outcomes. Articles were assessed by searching for hypertension and fasting, both as Medical Subject Headings (MeSH) terms and text words. The review included studies assessing Ramadan, intermittent, and water-only fasting. Water-only fasting reduces body weight, blood pressure, and lipolytic activity of fasting hypertensive patients without affecting average heart rate. Ramadan fasting enhances lipid profile, although it shows conflicting results for body weight, blood pressure, and heart rate variability. Considering the limited studies in this field, further research should be conducted to support the clinical impact of fasting on the cardiovascular health of patients with hypertension.

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.

Intermittent fasting for the prevention of cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death worldwide. Lifestyle changes are at the forefront of preventing the disease. This includes advice such as increasing physical activity and having a healthy balanced diet to reduce risk factors. Intermittent fasting (IF) is a popular dietary plan involving restricting caloric intake to certain days in the week such as alternate day fasting and periodic fasting, and restricting intake to a number of hours in a given day, otherwise known as time-restricted feeding. IF is being researched for its benefits and many randomised controlled trials have looked at its benefits in preventing CVD.

OBJECTIVES

To determine the role of IF in preventing and reducing the risk of CVD in people with or without prior documented CVD.

SEARCH METHODS

We conducted our search on 12 December 2019; we searched CENTRAL, MEDLINE and Embase. We also searched three trials registers and searched the reference lists of included papers. Systematic reviews were also viewed for additional studies. There was no language restriction applied.

SELECTION CRITERIA

We included randomised controlled trials comparing IF to ad libitum feeding (eating at any time with no specific caloric restriction) or continuous energy restriction (CER). Participants had to be over the age of 18 and included those with and without cardiometabolic risk factors. Intermittent fasting was categorised into alternate-day fasting, modified alternate-day fasting, periodic fasting and time-restricted feeding.

DATA COLLECTION AND ANALYSIS

Five review authors independently selected studies for inclusion and extraction. Primary outcomes included all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and heart failure. Secondary outcomes include the absolute change in body weight, and glucose. Furthermore, side effects such as headaches and changes to the quality of life were also noted. For continuous data, pooled mean differences (MD) (with 95% confidence intervals (CIs)) were calculated. We contacted trial authors to obtain missing data. We used GRADE to assess the certainty of the evidence.  MAIN RESULTS: Our search yielded 39,165 records after the removal of duplicates. From this, 26 studies met our criteria, and 18 were included in the pooled analysis. The 18 studies included 1125 participants and observed outcomes ranging from four weeks to six months. No studies included data on all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and heart failure at any point during follow-up. Of quantitatively analysed data, seven studies compared IF with ab libitum feeding, eight studies compared IF with CER, and three studies compared IF with both ad libitum feeding and CER. Outcomes were reported at short term (≤ 3 months) and medium term (> 3 months to 12 months) follow-up. Body weight was reduced with IF compared to ad libitum feeding in the short term (MD -2.88 kg, 95% CI -3.96 to -1.80; 224 participants; 7 studies; low-certainty evidence). We are uncertain of the effect of IF when compared to CER in the short term (MD -0.88 kg, 95% CI -1.76 to 0.00; 719 participants; 10 studies; very low-certainty evidence) and there may be no effect in the medium term (MD -0.56 kg, 95% CI -1.68 to 0.56; 279 participants; 4 studies; low-certainty evidence). We are uncertain about the effect of IF on glucose when compared to ad libitum feeding in the short term (MD -0.03 mmol/L, 95% CI -0.26 to 0.19; 95 participants; 3 studies; very-low-certainty of evidence) and when compared to CER  in the short term: MD -0.02 mmol/L, 95% CI -0.16 to 0.12; 582 participants; 9 studies; very low-certainty; medium term: MD 0.01, 95% CI -0.10 to 0.11; 279 participants; 4 studies; low-certainty evidence). The changes in body weight and glucose were not deemed to be clinically significant. Four studies reported data on side effects, with some participants complaining of mild headaches. One study reported on the quality of life using the RAND SF-36 score. There was a modest increase in the physical component summary score.

AUTHORS' CONCLUSIONS

Intermittent fasting was seen to be superior to ad libitum feeding in reducing weight. However, this was not clinically significant. There was no significant clinical difference between IF and CER in improving cardiometabolic risk factors to reduce the risk of CVD. Further research is needed to understand the safety and risk-benefit analysis of IF in specific patient groups (e.g. patients with diabetes or eating disorders) as well as the effect on longer-term outcomes such as all-cause mortality and myocardial infarction.

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

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

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

Background

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

Methods

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

Results

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

Conclusion

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

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Effects of Ramadan intermittent fasting on lipid and lipoprotein parameters: An updated meta-analysis

AIMS

This systematic review and meta-analysis aimed to clarify several aspects of intermittent fasting during the month of Ramadan on lipid and lipoprotein levels in apparently healthy subjects.

DATA SYNTHESIS

We searched PubMed, Scopus, and Embase databases and the reference lists of previous reviews, up to Feb 2019 for studies that investigated the effects of Ramadan fasting on fasting levels of triglycerides (TG), total cholesterol (TC), HDL-C, LDL-C, and VLDL-C among healthy subjects including pregnant women and athletic subjects. Studies were selected for quality assessment, meta-analyses, subgroup analyses, and meta-regressions; data of 33 eligible studies, conducted between 1978 and 2019, were included in the analysis.

RESULTS

Intermittent fasting showed no significant effect on circulating TG (WMD = -0.38 mg/dl, 95% CI = -5.33, 4.57), TC (WMD = -1.58 mg/dl, 95% CI = -6.04, 2.88), and LDL-C levels (WMD = 1.85 mg/dl, 95% CI = 0.77, 2.92). Overall, HDL-C (WMD = -2.97 mg/dl; 95% CI = -6.43, 0.48 mg/dl) and VLDL-C (WMD = -1.41 mg/dl; 95% CI = -2.73, -0.10 mg/dl) significantly decreased after Ramadan fasting. A significant increase in LDL-C levels was observed in athletic subjects (WMD = 2.97 mg/dl; 95% CI = 0.80, 5.13) and apparently healthy subjects (WMD = 1.81 mg/dl; 95% CI = 0.55, 3.07). Change in TG levels was associated with age (β = -0.94, P = 0.043), its baseline values (β = -0.44, P = 0.001), and weight change during the fasting period (β = -0.57, P = 0.032).

CONCLUSION

Ramadan fasting may be accompanied by a moderate improvement of lipid and lipoprotein parameters, especially HDL-C levels; fasting appears to be more beneficial for men and athletic subjects.

Metabolic effects of Ramadan fasting in patients at high risk of cardiovascular diseases

BACKGROUND AND AIM

The effects of Ramadan fasting on health are a little controversial. The present study is aimed at evaluating the metabolic effects on a group of 517 patients with ≥2 cardiovascular risk factors over a period running from 2012 to 2014.

METHODS

Each patient was assessed at three visits: before, during, and after Ramadan. Demographical, clinical and biological tests were performed at each visit.

RESULTS

Metabolically, we noted a significant and discrete rise in blood glucose level (+1.2 mmol/L), triglycerides (+0.3 mmol/L), cholesterol (+0.12 mmol/L) and creatinine (+3 µmol/L) during Ramadan. These disturbances decreased significantly after Ramadan. The same variations were observed among diabetics (n=323). However, there was a significant decrease in HbA1c after Ramadan (9.0% vs 7.6%, p<0.001). Our findings also revealed there was no significant correlation between variations of metabolic parameters and dietary intake. No acute metabolic incidents were reported during the study period.

CONCLUSION

The current study showed that Ramadan is responsible for a transient but well tolerated disturbance of metabolic parameters followed by a significant post-Ramadan improvement. These changes did not seem to be directly related to dietary intake.

Effect of Ramadan Fasting on Weight and Body Composition in Healthy Non-Athlete Adults: A Systematic Review and Meta-Analysis

Background: Ramadan involves one month of fasting from sunrise to sunset. In this meta-analysis, we aimed to determine the effect of Ramadan fasting on weight and body composition. Methods: In May 2018, we searched six databases for publications that measured weight and body composition before and after Ramadan, and that did not attempt to influence physical activity or diet. Results: Data were collected from 70 publications (90 comparison groups, 2947 participants). There was a significant positive correlation between starting body mass index and weight lost during the fasting period. Consistently, there was a significant reduction in fat percentage between pre-Ramadan and post-Ramadan in people with overweight or obesity (−1.46 (95% confidence interval: −2.57 to −0.35) %, p = 0.010), but not in those of normal weight (−0.41 (−1.45 to 0.63) %, p = 0.436). Loss of fat-free mass was also significant between pre-Ramadan and post-Ramadan, but was about 30% less than loss of absolute fat mass. At 2–5 weeks after the end of Ramadan, there was a return towards, or to, pre-Ramadan measurements in weight and body composition. Conclusions: Even with no advice on lifestyle changes, there are consistent—albeit transient—reductions in weight and fat mass with the Ramadan fast, especially in people with overweight or obesity.

The role of inflammatory markers following Ramadan Fasting

Objectives:

The aim of present study was to investigate the effect of fasting during Ramadan on plasma adiponectin and TNF-α levels.

Methods:

This is a cross sectional study, conducted at Federal Urdu University of Arts, Science & Technology (FUUAST), Karachi, comprising a total of 55 (50%) females and 55 (50%) males whose ages ranged between 20 and 40 years, and fasted during Ramadan (June-July 2014) were enrolled in the study. Subjects were separated into normal weight, overweight and obese males and females. Anthropometric measurements and Fasting venous blood samples were taken at first and last (29^th) day of Ramadan. Plasma adiponectin and TNF-alpha levels were assayed with ELISA kits. All values were calculated and presented as mean ± standard error of the mean (SEM) and by using analysis of variance (ANOVA) for repeated measures. P values < 0.05 were accepted as significant.

Results:

Body mass index (BMI) (Kg/m2) in over-weight and obese male subjects exhibited considerable reduction (P<0.05; P<0.05), post Ramadan when compared to their respective pre Ramadan fasting weights. Noticeable and significant reduction was also observed in BMI of obese females (P<0.05). Post Ramadan Overweight Males (P<0.05) and Post Ramadan Obese Males (P<0.001) exhibited significantly elevated plasma adiponectin (μg/mL) values. While plasma adiponectin mean concentration of only obese females were significantly improved at last week of Ramadan (P<0.01). Fasting in Ramadan significantly decreased TNF-α (pg/mL) levels of post obese males and females than Pre-Ramadan-groups (P<0.05; P<0.01) respectively.

Conclusion:

The study reports of noticeable changes with Ramadan fasting resulting increase of plasma adiponectin and decrease of TNF-α levels as well as body weight. The study strongly suggests further investigations on larger sample sizes with possible association of dietary restrictions and weight loss on mechanism of enhanced adiponectin and reduced TNF-α in obese and overweight persons who fast on Ramadan pattern.

Intermittent Fasting During Ramadan Improves Insulin Sensitivity and Anthropometric Parameters in Healthy Young Muslim Men

The current study aimed to determine the effect of fasting during Ramadan on the metabolic profile, anthropometry, and serum leptin and adiponectin concentrations. Anthropometry and blood samples were examined at 2 phases: baseline (within 3 days of the start of the Ramadan fast) and end-line (in the last 3 days before the end of the Ramadan fast) in 27 healthy Muslim male participants who completed Ramadan fasting. Results demonstrate reductions in body weight (P < .001), body mass index (P < .001), fat mass (P = .003), muscle mass (P = .004), and waist circumference (P < .001) following reductions in energy intake (P = .003). Insulin sensitivity was improved. Serum insulin concentration and homeostatic model assessment of insulin resistance decreased significantly (P = .005 and P = .009). No significant change in fasting plasma glucose was observed. Correlation coefficients showed a significant correlation between the percentage changes in body weight and percentage changes in serum leptin concentration (r = 0.412; P = .037). These results demonstrate that intermittent fasting during Ramadan leads to beneficial effects by improving insulin sensitivity. It also resulted in a beneficial effect on weight and fat loss.

Time-restricted feeding influences immune responses without compromising muscle performance in older men

OBJECTIVE

This study examined the effect of 12 wk of time-restricted feeding (TRF) on complete blood cell counts, natural killer cells, and muscle performance in 20- and 50-year-old men.

METHODS

Forty active and healthy participants were randomly divided into young experimental, young control, aged experimental, and aged control group. Experimental groups participated in TRF. Before (P1) and after (P2) TRF, participants performed a maximal exercise test to quantify muscle power. Resting venous blood samples were collected for blood count calculation.

RESULTS

No changes were identified in muscle power in all groups after TRF (P > 0.05). At P1, red cells, hemoglobin, and hematocrit were significantly higher in young participants compared with elderly participants (P < 0.05). At P2, this age effect was not found in red cells between the young experimental group and the aged experimental group (P > 0.05). At P1, white blood cells and neutrophils were significantly higher in young participants compared with elderly participants (P < 0.05). At P2, only neutrophils decreased significantly (P < 0.05) in experimental groups without significant (P > 0.05) difference among them. Lymphocytes decreased significantly in the aged experimental group at P2 (P < 0.05), whereas NKCD16⁺ and NKCD56⁺ decreased significantly in experimental groups at P2 (P < 0.05). TRF had no effect on CD3, CD4⁺, and CD8⁺ levels (P > 0.05).

CONCLUSION

TRF decreases hematocrit, total white blood cells, lymphocytes, and neutrophils in young and older men. TRF may be effective in preventing inflammation by decreasing natural killer cells. As such, TRF could be a lifestyle strategy to reduce systemic low-grade inflammation and age-related chronic diseases linked to immunosenescence, without compromising physical performance.

The Effect of Ramadan Fasting on Biochemical Parameters in Healthy Thai Subjects

Introduction

Although, the effect of Ramadan fasting on the risks for Cardiovascular Disease (CVD) has been reported in several studies, the results were inconsistent. In addition, the effect of Ramadan fasting on biochemical parameters in Thai subjects has not been evaluated.

Aim

The aim of this study was to investigate the effect of Ramadan fasting on anthropometry, blood pressure, Fasting Blood Glucose (FBG), lipid profiles, and body composition in healthy Thai subjects.

Materials and Methods

A total of 65 healthy subjects (21 men and 44 women) aged between 19-24 years were randomly recruited. Anthropometry, blood pressure, FBG, Total Cholesterol (TC), Triglyceride (TG), High Density Lipoprotein-Cholesterol (HDL-C), Low Density Lipoprotein-Cholesterol (LDL-C), and body composition were measured before Ramadan, end of Ramadan and after one month of Ramadan.

Results

There were no changes in anthropometry, blood pressure, lipid profiles and body composition in both genders before Ramadan, end of Ramadan and after one month of Ramadan. Nevertheless, FBG levels were significantly increased after one month of Ramadan compared with baseline (5.09±0.50 versus 4.83±0.38 mmol/L, p=0.016, respectively) in women.

Conclusion

The Ramadan fasting did not affect the lipid, anthropometric and body composition in healthy Thai subjects. However, the increased FBG levels after one month of Ramadan were observed in women. To improve the favourable biochemical parameters after Ramadan fasting, the lifestyle modifications such as, increased intake of healthy diets and increased physical activity should be recommended.

Impact of Time-Restricted Feeding and Dawn-to-Sunset Fasting on Circadian Rhythm, Obesity, Metabolic Syndrome, and Nonalcoholic Fatty Liver Disease

Obesity now affects millions of people and places them at risk of developing metabolic syndrome, nonalcoholic fatty liver disease (NAFLD), and even hepatocellular carcinoma. This rapidly emerging epidemic has led to a search for cost-effective methods to prevent the metabolic syndrome and NAFLD as well as the progression of NAFLD to cirrhosis and hepatocellular carcinoma. In murine models, time-restricted feeding resets the hepatic circadian clock and enhances transcription of key metabolic regulators of glucose and lipid homeostasis. Studies of the effect of dawn-to-sunset Ramadan fasting, which is akin to time-restricted feeding model, have also identified significant improvement in body mass index, serum lipid profiles, and oxidative stress parameters. Based on the findings of studies conducted on human subjects, dawn-to-sunset fasting has the potential to be a cost-effective intervention for obesity, metabolic syndrome, and NAFLD.

Effects of intermittent fasting and chronic swimming exercise on body composition and lipid metabolism

Intermittent fasting protocol (IFP) has been suggested as a strategy to change body metabolism and improve health. The effects of IFP seem to be similar to aerobic exercise, having a hormetic adaptation according to intensity and frequency. However, the effects of combining both interventions are still unknown. Therefore, the aim of the present study was to evaluate the effects of IFP with and without endurance-exercise training on body composition, food behavior, and lipid metabolism. Twenty-week-old Wistar rats were kept under an inverted circadian cycle of 12 h with water ad libitum and assigned to 4 different groups: control group (ad libitum feeding and sedentary), exercise group (ad libitum feeding and endurance training), intermittent fasting group (IF; intermittent fasting and sedentary), and intermittent fasting and exercise group (IFEX; intermittent fasting and endurance training). After 6 weeks, the body weight of IF and IFEX animals decreased without changes in food consumption. Yet, the body composition between the 2 groups was different, with the IFEX animals containing higher total protein and lower total fat content than the IF animals. The IFEX group also showed increases in total high-density lipoprotein cholesterol and increased intramuscular lipid content. The amount of brown adipose tissue was higher in IF and IFEX groups; however, the IFEX group showed higher expression levels of uncoupling protein 1 in this tissue, indicating a greater thermogenesis. The IFP combined with endurance training is an efficient method for decreasing body mass and altering fat metabolism, without inflicting losses in protein content.

Effects of Ramadan fasting on moderate to severe chronic kidney disease. A prospective observational study

Objectives:

To examin the effect of Ramadan fasting on worsening of renal function (WRF).

Method:

This was a single-arm prospective observational study including 65 patients with stage 3 or higher chronic kidney disease (CKD). By definition, WRF was considered to have occurred when serum creatinine levels increased by 0.3 mg/dL (26.5 µmol/l) from baseline during or within 3 months after Ramadan. The study was conducted in the Nephrology Clinic of King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia during the month of Ramadan 1436 AH (Hijiri), which corresponded to June 18-July 17, 2015.

Results:

This study included 65 adults with a mean age of 53 years. Overall, 33% of patients developed WRF. In the multivariate analysis, more advanced CKD stage, higher baseline systolic blood pressure and younger age were independently associated with WRF. Underlying cause of CKD, use of diuretics, use of renin angiotensin blockers, gender, and smoking status were not associated with WRF.

Conclusion:

In patients with stage 3 or higher CKD, Ramadan fasting during the summer months was associated with worsening of renal function. Clinicians need to warn CKD patients against Ramadan fasting.

Matching Meals to Body Clocks-Impact on Weight and Glucose Metabolism

The prevalence of type 2 diabetes continues to rise worldwide and is reaching pandemic proportions. The notion that this is due to obesity, resulting from excessive energy consumption and reduced physical activity, is overly simplistic. Circadian de-synchrony, which occurs when physiological processes are at odds with timing imposed by internal clocks, also promotes obesity and impairs glucose tolerance in mouse models, and is a feature of modern human lifestyles. The purpose of this review is to highlight what is known about glucose metabolism in animal and human models of circadian de-synchrony and examine the evidence as to whether shifts in meal timing contribute to impairments in glucose metabolism, gut hormone secretion and the risk of type 2 diabetes. Lastly, we examine whether restricting food intake to discrete time periods, will prevent or reverse abnormalities in glucose metabolism with the view to improving metabolic health in shift workers and in those more generally at risk of chronic diseases such as type 2 diabetes and cardiovascular disease.

Study of Human Biochemical Parameters During and After Ramadan

Ramadan fasting is obligatory for Muslims each year. They abstain from drinking, eating and intimate relationship between dawn and dusk during this month. Dietary restriction during Ramadan has various biochemical and physiological effects. It is shown to decrease the body weight, glucose and lipid profile. This study aims to analyze the changes in body weight, glucose and lipid profile during Ramadan in physiotherapy students in Pakistan. The study was conducted during June-July 2013 (Hijri year 1434). There were 80 students (50 males and 30 females) recruited in the experiment. They all were healthy adults between the age group of 18-24 (mean age 20.5) years. All subjects underwent a general physical examination and interview, and non-healthy subjects were excluded. On statistical analysis, quantitative data were expressed in terms of mean ± SD and a p value of ≤0.05 was believed statically significant. Paired t test was used to compare the variables. There was a little reduction in body weight (62.7 ± 8.8 vs. 62.3 ± 9.0; p value = 0.009) but a significant decline in glucose level (72.6 ± 12.5 vs. 57.9 ± 10.7; p value = 0.000), low-density lipoprotein level (2.9 ± 0.3 vs. 2.5 ± 0.3; p value = 0.000), total cholesterol (4.6 ± 0.4 vs. 4.2 ± 0.5; p value = 0.000) and triglycerides (1.4 ± 0.5 vs. 1.2 ± 0.5; p value = 0.000) was observed. Moreover, there was some reduction in high-density lipoprotein cholesterol level (1.2 ± 0.3 vs. 1.1 ± 0.3; p value = 0.045). This study shows that Ramadan fasting, a religious obligation for purification of body and soul, resulted in reduced body weight and a positive effect on glucose level and lipid profile.

Diabetes and Ramadan: A concise and practical update

Despite the fact that the month of Ramadan includes 29–30 days and the duration of fasting for each day can last for between 12 and 16 h, it was estimated that a large number of individuals with diabetes do fast during Ramadan. In light of recent advancement of new pharmacological agents, drugs such as vildagliptin, sitagliptin, and liraglutide were found to be safe to use during this month of fasting. These therapeutic agents can also be used in combination with metformin. The use of sulfonylureas, in most of the recent guidelines about diabetes and Ramadan, seems not to gain much support due to the risk of hypoglycemia. In this review, we also addressed the use of insulin injection, insulin pump, and education before, during, and after Ramadan. Further research is needed to determine (i) the therapeutic benefit of new antidiabetic agents and (ii) the benefit of new technologies for the treatment of diabetes.

Does Lipid Profile Affect Thrombin Generation During Ramadan Fasting in Patients With Cardiovascular Risks?

There is evidence that diet and variation in lipid metabolism can influence blood coagulation, but little is known about the effect of Ramadan fasting on plasmatic coagulation pattern. We investigated the effect of Ramadan fasting on thrombin generation (TG) in patients with cardiovascular disease (CVD) risks, and we aimed to assess the effect of lipid profile on TG parameters. The study was conducted in 36 adults having at least 2 CVD risks and in 30 healthy controls. Coagulation pattern was assessed by both classical clotting times and TG test. A complete lipid profile was performed simultaneously. Patients were invited 2 times: 1 week before Ramadan and during the last week of the Ramadan. The TG parameters were not different in patients with CVD risks compared to healthy controls. Fasting had no effect on plasmatic coagulation parameters and on TG profile. Individual analysis of the mean rate index (MRI) of TG revealed 3 groups: group 1 with no modification of MRI, group 2 with a significant increase in MRI (81.64 nM/min vs 136.07 nM/min; P < .001), and group 3 with a significant decrease in MRI (125.27 nM/min vs 73.18 nM/min; P = .001). Only in group 2, a significant increase was observed in total cholesterol and low-density lipoprotein cholesterol. Changes in lipid profile during Ramadan fasting did not influence the global coagulation pattern in patients with CVD risks. Whereas, a significant increase in the propagation phase of TG was associated with a significant increase in cholesterol levels, which was not found with the other TG parameters.

Effects of Ramadan fasting on glucose homeostasis and adiponectin levels in healthy adult males

BACKGROUND

Adiponectin is a hormone secreted by adipocytes during the fasting phase of the fast-fed cycle. Ramadan fasting involves prolonged fasting for up to twelve hours and thus could lead to increased secretion of adiponectin by adipocytes. However, studies on the role of adiponectin on glucose and body weight homeostasis during Ramadan fasting is still a matter of controversy. Thus the specific aim of this study was to assess the effect of fasting during Ramadan on the adiponectin levels, body weight and glucose homeostasis in healthy male Malaysian subjects.

METHODS

Twenty healthy male (19-23 years) Muslim subjects were followed up during the fasting month of Ramadan. Anthropometry and blood samples were taken one week before and during the fourth week of fasting. Plasma glucose, insulin and adiponectin were estimated and insulin sensitivity indices were estimated using the Homeostasis Model Assessment.

RESULTS

Subjects experienced a significant decrease in body weight (2.4 %, p < 0.001) and body mass index (5.5 %, p < 0.01). There was also a significant decrease of 12.3 %, 52.8 % and 45.6 % of plasma glucose, insulin and adiponectin respectively (p < 0.01). The drop in adiponectin was positively correlated with the decrease in body weight (r = 0.45, p < 0.05). There was also a significant increase in insulin sensitivity and a decrease in insulin resistance (p < 0.01).

CONCLUSIONS

These results indicate that Ramadan fasting in young healthy individuals has a positive impact on the maintenance of glucose homeostasis. It also shows that adiponectin levels dropped along with significant loss in weight. We feel caloric restriction during the Ramadan fasting is in itself sufficient to improve insulin sensitivity in healthy individuals.

The effects of intermittent fasting during the month of Ramadan in chronic haemodialysis patients in a tropical climate country

Background

Chronic kidney disease is an emerging problem in the majority Muslim countries. Despite the uncertainties of the risks involved, some Muslim patients undergoing chronic haemodialysis choose to observe intermittent fasting during the month of Ramadan. This study aims to investigate the effect of Ramadan fasting in haemodialysis patients residing in a tropical climate country.

Methods

This prospective cross sectional study recruited Muslim patients on regular haemodialysis from three haemodialysis centres in Kuala Lumpur from 15^th July 2011 to 29^th August 2011. Patients who fasted for any number of days were included (n = 35, 54% female, age 54±11 years). 89% of patients fasted for more than 15 days and 49% were diabetics. Dialysis parameters and blood samples were obtained one week prior to Ramadan and during the last week of Ramadan. The differences in dialysis parameters and biochemical values pre- and end-Ramadan were examined using paired t-test.

Results

Both pre- and post-dialysis weight were significantly decreased during Ramadan fasting compared to the month prior (p = <0.001). There was a significant decrease in the amount of ultrafiltration (p = 0.002). There were no significant differences in dry weight, inter-dialytic weight gain, mean urea reduction ratio or blood pressure measurements comparing pre- and end of Ramadan fasting. There was a significant increase in serum albumin level (p = 0.006) and decrease in serum phosphate level (p = 0.02) at the end of Ramadan.

Conclusion

Ramadan fasting is associated with reduced weight, improved serum albumin and phosphate level in our population of haemodialysis patients. A larger multi-centre study will allow us to understand more about the effects of fasting in this population.

Islamic fasting and weight loss: a systematic review and meta-analysis

OBJECTIVE

Studies on the effects of Ramadan fasting on weight changes have been contradictory. We brought together all published data to comprehensively examine the effects in a systematic review and meta-analysis.

DESIGN

Relevant studies were obtained through searches of PubMed and CINAHL and by independent screening of reference lists and citations without any time restriction. All searches were completed between October and November 2011.

SETTING

Changes in body weight during and after Ramadan were extracted from thirty-five English-language studies and were meta-analysed. Most of the studies were conducted in West Asia (n 19); the remainder were conducted in Africa (n 7), East Asia (n 3) and North America/Europe (n 4).

SUBJECTS

Healthy adults.

RESULTS

Fasting during Ramadan resulted in significant weight loss (-1·24 kg; 95% CI -1·60, -0·88 kg). However, most of the weight lost was regained within a few weeks and only a slight decrease in body weight was observed in the following weeks after Ramadan compared with that at the beginning of Ramadan. Weight loss at the end of Ramadan was significant in both genders (-1·51 kg for men and -0·92 kg for women); but again the weight loss lasted no longer than 2 weeks after Ramadan. Weight loss during Ramadan was greater among Asian populations compared with Africans and Europeans.

CONCLUSIONS

Weight changes during Ramadan were relatively small and mostly reversed after Ramadan, gradually returning to pre-Ramadan status. Ramadan provides an opportunity to lose weight, but structured and consistent lifestyle modifications are necessary to achieve lasting weight loss.

Ramadan fasting ameliorates oxidative stress and improves glycemic control and lipid profile in diabetic patients

PURPOSE

The effects of Ramadan fasting on public health are important. The present study characterized the metabolic effects of Ramadan fasting and evaluated its influence on oxidative stress in diabetic patients.

METHODS

The current study was carried out in the city of Benha, Egypt, during the period from July 12, 2012 to October 4, 2012. This corresponds to 22 Shaban 1433 to 18 Dhul Al-Qi'dah 1433 in the Islamic Calendar. Two equal, sex- and age-matched groups (n = 40 each; age 55 ± 5 years) of non-diabetic subjects (ND group) and diabetic patients (D group) were recruited for this study. Parameters of glycemic control, lipid profile, and oxidative stress were measured pre-, during and post-fasting.

RESULTS

Ramadan fasting reduced fasting blood glucose (FBG) insignificantly by 5.8% and significantly by 23.0% in the (ND) and (D) groups, respectively. Serum triglycerides (TG) and malondialdehyde (MDA) were lowered significantly by: TG (22.8, 22.1%), MDA (54.3, 46.6%), and total cholesterol (TC) and low-density lipoproteins (LDL) insignificantly by: TC: (4.7, 6.1%), LDL: (4.0, 5.1%), whereas high-density lipoproteins (HDL) were raised significantly by 6.7% and insignificantly by 2.2%, and blood glutathione (GSH) significantly by 52.6 and 59.4%, in the (ND) and (D) groups, respectively. At 6 weeks post-fasting FBG, TG, TC, HDL, and LDL returned to levels indistinguishable from their baseline values in both groups, while MDA was maintained significantly lower by (25.7, 22.7%), and GSH significantly higher by (26.3, 31.3%), in the (ND) and (D) groups, respectively.

CONCLUSIONS

Ramadan fasting improves glycemic control and lipids profile and alleviates oxidative stress in diabetics.

Effects of intermittent fasting on metabolism in men

This review analyzes the available literature on the impact of intermittent fasting (IF), a nutritional intervention, on different aspects of metabolism. The epidemic of metabolic disturbances, such as obesity, metabolic syndrome (MS), and diabetes mellitus type 2 has led to an increase in the prevalence of cardiovascular diseases, and affected patients might significantly benefit from modifications in nutritional habits. Recent experimental studies have elucidated some of the metabolic mechanisms involved with IF. Animal models have shown positive changes in glucose (lower plasma glucose and insulin levels) and in lipid metabolism (reduced visceral fat tissue and increased plasma adiponectin level), and an increased resistance to stress. Despite the limited number of samples studied, positive results have been reported on the impact of IF for human health. IF is reported to improve the lipid profile; to decrease inflammatory responses, reflected by changes in serum adipokine levels; and to change the expression of genes related to inflammatory response and other factors. Studies on obese individuals have shown that patient compliance was greater for IF than other traditional nutritional approaches (calorie restriction), and IF was found to be associated with low oxidative stress. Recent reports suggest that IF exerts a positive impact on the metabolic derangements commonly associated with cardiovascular diseases, and that it may be a viable and accessible intervention for most individuals. Therefore, further clinical studies are essential to test the effectiveness of IF in preventing and controlling metabolic and cardiovascular diseases.

Ramadan fasting ameliorates arterial pulse pressure and lipid profile, and alleviates oxidative stress in hypertensive patients

BACKGROUND AND AIM

Effects of Ramadan fasting on health are important. Its effects on arterial pulse pressure (PP), lipid profile and oxidative stress were characterized in hypertensives.

METHODS

PP, indices of lipid profile and oxidative stress were measured pre-, during and post-fasting in equal (40 each), sex- and age-matched groups (age 55 ± 5 years) of hypertensives (HT) and controls (C).

RESULTS

Fasting reduced PP significantly by 17.2% and insignificantly by 9.3% in the HT and C groups, respectively. Total cholesterol (TC) was lowered insignificantly by 11.7% and 4.7% in the HT and C patients, respectively. Triglycerides (TG) and malondialdehyde (MDA) were significantly lowered by: TG: 24.5% and 22.8%; MDA: 45.6% and 54.3%; while glutathione (GSH) elevated by 56.8% and 52.6% in the HT and C groups, respectively. High-density lipoproteins (HDL) were raised significantly by 33.3% and insignificantly by 6.7%, whereas low-density lipoproteins (LDL) decreased significantly by 17.7% and insignificantly by 4.0% in the HT and C groups, respectively. At 6 weeks post-fasting, MDA remained significantly lower than the pre-fasting level by 24.3% and 25.7%, and GSH higher by 30.2% and 26.3% in the HT and C groups, respectively, while PP and TC returned to pre-fasting values in both groups. The post-fasting, HDL was significantly higher by 20.3% and LDL lower by 12.0% than the fasting levels in the HT patients.

CONCLUSION

Fasting improves PP and lipids profile and ameliorates oxidative stress in hypertensives.

Impact of religious Ramadan fasting on cardiovascular disease: a systematic review of the literature

BACKGROUND

Fasting during the month of Ramadan is a religious obligation that is practiced by millions of people around the world yet there is no clear scientific consensus on its effects on cardiovascular disease. This study was performed to inform physicians as well as patients of evidence based recommendations on this subject.

AIM

The study was undertaken to assess: (1) any alteration in the incidence of acute cardiac illness during Ramadan fasting; (2) whether fasting during the month of Ramadan alters the clinical status of patients with stable cardiac disease; and (3) the impact of Ramadan fasting on cardiovascular risk factors in normal subjects, in patients with stable cardiac disease, metabolic syndrome, dyslipidemia, type 2 diabetes and systemic hypertension.

STUDY DESIGN

Systematic review of the literature.

METHOD

A Medline search of the English literature published between January 1980 and September 2012.

RESULTS

The incidence of acute cardiac illness during Ramadan fasting was similar to non-fasting days, although the timing of symptom onset may be different, with significant increase in events during the period of 'breaking fast' when compared to non-fasting days. The majority of patients with stable cardiac illness can undergo Ramadan fasting without any clinical deterioration. Body mass index, lipid profile, and blood pressure showed significant improvement in normal healthy subjects, patients with stable cardiac illness, metabolic syndrome, dyslipidemia and hypertension during Ramadan fasting. The lipid profile of diabetic patients deteriorated significantly during Ramadan fasting.

CONCLUSIONS

Ramadan fasting is not associated with any change in incidence of acute cardiac illness and the majority of cardiac patients can fast without any difficulty. Improvement in lipid profile, especially 30% to 40% increment in high-density lipoprotein, as reported in some studies, appear promising. Diabetic patients should be carefully monitored during Ramadan fasting.

The effect of ramadan fasting and physical activity on body composition, serum osmolarity levels and some parameters of electrolytes in females

BACKGROUND

So far, there have been a few and incoherent results about the effects of physical activities. Fasting in Ramadan has an effect on the level of osmolarity and the concentration of serum electrolytes both in active and inactive females.

OBJECTIVES

The aim of this study was to observe the changes of serum electrolytes and osmolarity levels according to regular exercise during fasting.

PATIENTS AND METHODS

TWENTY TWO HEALTHY FEMALES WHO WERE ELECTED BY CONVENIENCE SAMPLING METHOD WERE DIVIDED INTO TWO GROUPS: 1) fasting + exercise (FE; n = 11) and 2) fasting + non exercise (FNE; n = 15). The FE group participated in aerobic training for four sessions per week during the fasting. All measurements were done once before the first day, on the second week, on the fourth week and two weeks after fasting month and these measures were used to analyze test results.

RESULTS

THE MEAN DIFFERENCES WERE AS FOLLOWS: significant weight loss, BMI, WHR, in two groups at the end of Ramadan (P < 0.05). The mean of weight, BMI, WHR, body fat, protein, mineral and total water showed no difference between groups (P > 0.05). Potassium, creatinine, urea and uric acid had been decreased significantly in both groups (P < 0.05). Variance between groups was significant only in variable urea (P < 0.05). Variations within group had been changed in FBS; sodium, phosphorus and osmolarity levels were not changed significantly.

CONCLUSIONS

According to this result, regular exercise in case of fasting in Ramadan led to some changes in serum osmolarity index, electrolytes and water. Therefore, it is important for female athletes to consider applying a suitable nutritious diet and sufficient water consumption during Ramadan.

Impact of ramadan intermittent fasting on oxidative stress measured by urinary 15-f(2t)-isoprostane

Fasting and caloric restriction have been associated with reduced incidence of chronic diseases and cancers. These effects have been attributed to reduced oxidative stress. Since Ramadan intermittent fasting (RIF) has been associated with reduced caloric intake, it was hypothesized that RIF would alleviate oxidative stress in healthy volunteers. The study was designed to elucidate the impact of RIF on oxidative stress measured by 15-F_2t-Isoprostane (15FIP). Fifty healthy subjects (23 men and 27 women) who intended to fast Ramadan were recruited. Urine and serum sampling and anthropometric and dietary assessments were conducted one week before Ramadan (T0), at the end of the third week of Ramadan (T1), and one month after Ramadan (T2). Biochemical measurements included urinary 15FIP, creatinine, and hematological indices. Results revealed that the urinary level of 15FIP measured at T0 was normal, while they showed a significantly (P < 0.05) higher level when measured at T1 concomitant with a significant (P < 0.05) increase in the body weight and total body fat percent. In conclusion, results suggest that increased body weight is associated with increased lipid peroxidation and oxidative stress, and the impact of RIF on oxidative stress is mediated by the changes in body weight at the end of the month.

Effects of Ramadan fasting on cardiovascular risk factors: a prospective observational study

Background

Previous research has shown that Ramadan fasting has beneficial effects on cardiovascular risk factors, however there are controversies. In the present study, the effect of Ramadan fasting on cardiovascular risk factors has been investigated.

Method

This is a prospective observational study that was carried out in a group of patients with at least one cardiovascular risk factor (including history of documented previous history of either coronary artery disease (CAD), metabolic syndrome or cerebro-vascular disease in past 10 y). Eighty two volunteers including 38 male and 44 female, aged 29–70 y, mean 54.0 ± 10 y, with a previous history of either coronary artery disease, metabolic syndrome or cerebro-vascular disease were recruited. Subjects attended the metabolic unit after at least 10 h fasting, before and after Ramadan who were been fasting for at least 10 days. A fasting blood sample was obtained, blood pressure was measured and body mass index (BMI) was calculated. Lipids profile, fasting blood sugar (FBS) and insulin, homocysteine (hcy), high-sensitivity C-reactive protein (hs-CRP) and complete blood count (CBC) were analyzed on all blood samples.

Results

A significant improvement in 10 years coronary heart disease risk (based on Framingham risk score) was found (13.0 ± 8 before Ramadan and 10.8 ±7 after Ramadan, P <0.001, t test).There was a significant higher HDL-c, WBC, RBC and platelet count (PLT), and lower plasma cholesterol, triglycerides, LDL-c, VLDL-c, systolic blood pressure, body mass index and waist circumference after Ramadan (P <0.05, t test). The changes in FBS, insulin,Homeostasis Model Assessment Insulin Resistance (HOMA-IR), hcy, hs-CRP and diastolic blood pressure before and after Ramadan were not significant (P >0.05, t test).

Conclusions

This study shows a significant improvement in 10 years coronary heart disease risk score and other cardiovascular risk factors such as lipids profile, systolic blood pressure, weight, BMI and waist circumference in subjects with a previous history of cardiovascular disease.