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

The effects of camel milk (CM) intake on glycemic control in patients with diabetes are controversial. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize the effect of CM intake on glucose homeostasis parameters in patients with both types of diabetes mellitus; T1DM and T2DM. We searched Google Scholar, PubMed/MEDLINE, EBSCO host, CINAHL, ScienceDirect, Cochrane, ProQuest Medical, Web of Science, and Scopus databases from inception until the end of November 2021. Relevant RCTs were identified, and the effect size was reported as mean difference (MD) and standard deviation (SD). Parameters of glycosylated hemoglobin (HbA1c), fasting blood glucose (FBG), postprandial blood glucose (PBG), fasting serum insulin (FI), insulin resistance (expressed in terms of HOMA-IR), insulin dose (ID) received, serum insulin antibody (IA), and C-peptide (CP) were tested. Out of 4054 collected articles, 14 RCTs (total 663 subjects) were eligible for inclusion. The pooled results obtained using a random-effects model showed a statistically significant decrease in HbA1c levels (MD, −1.24, 95% confidence interval (CI): −2.00, −0.48, p < 0.001 heterogeneity (I²) = 94%) and ID received (MD, −16.72, 95% CI: −22.09, −11.35 p < 0.00001, I² = 90%), with a clear tendency was shown, but non-significant, to decrease FBG (MD, −23.32, 95% CI: −47.33, 0.70, p = 0.06, I² = 98%) in patients with diabetes who consumed CM in comparison to those on usual care. Conversely, the consumption of CM did not show significant reductions in the rest of the glucose homeostasis parameters. Subgroup analysis revealed that patients with T2DM were more beneficially affected by CM intake than those with T1DM in lowering FBG, while patients with T1DM were more beneficially affected by CM intake than those with T2DM in lowering HbA1c. Both fresh and treated (pasteurized/fermented) CM gave similar beneficial effects in lowering HbA1c. Lastly, a relatively superior effect for longer duration on shorter duration (>6 months, ≤6 months, respectively) of CM intake is found in lowering HbA1c. To conclude, long-term consumption of CM by patients with diabetes could be a useful adjuvant therapy alongside classical medications, especially in lowering the required insulin dose and HbA1c. Due to the high heterogeneity observed in the included studies, more controlled trials with a larger sample size are warranted to confirm our results and to control some confounders and interfering factors existing in the analyzed articles.

Context: Ramadan fasting (RF) is associated with various physiological and metabolic changes among fasting Muslims. However, it remains unclear whether these effects are attributable to changes in meal timing or changes in dietary energy and macronutrient intakes. Furthermore, the literature on the associations between RF, meal timing, and energy and macronutrient intakes is inconclusive. Objectives: This systematic review aimed to estimate the effect sizes of RF on energy and macronutrient intakes (carbohydrates, protein, fats, dietary fiber, and water) and determine the effect of different moderators on the examined outcomes. Data Sources: The Cochrane, CINAHL, EMBASE, EBSCOhost, Google Scholar, PubMed/MEDLINE, ProQuest Medical, Scopus, ScienceDirect, and Web of Science databases were searched from inception to January 31, 2022. Data Extraction: The studies that assessed energy, carbohydrate, protein, fat, fiber, and water intakes pre- and post-fasting were extracted. Data Analysis: Of the 4776 identified studies, 85 relevant studies (n = 4594 participants aged 9–85 y) were selected. The effect sizes for the studied variables were as follows: energy (number of studies [K] = 80, n = 3343 participants; mean difference [MD]: −142.45; 95% confidence interval [CI]: −215.19, −69.71), carbohydrates (K = 75, n = 3111; MD: −23.90; 95% CI: −36.42, −11.38), protein (K = 74, n = 3108; MD: −4.21; 95% CI: −7.34, −1.07), fats (K = 73, n = 3058; MD: −2.03; 95% CI: −5.73, 1.67), fiber (K = 16, n = 1198; MD: 0.47; 95% CI: −1.44, 2.39), and water (K = 17, n = 772; MD: −350.80; 95% CI: −618.09, 83.50). Subgroup analyses showed age significantly moderated the 6 dietary outcomes, and physical activity significantly moderated water intake. There were significant reductions in energy, carbohydrate, and protein intakes during RF. Conclusions: The change in meal timing rather than quantitative dietary intake may explain various physiological and health effects associated with RF.

Purpose: People with food allergies rely to a great extent on restaurant staff to have a safe meal. The purpose of this paper is to acquire novel data to evaluate knowledge, attitudes and practices of food allergy among the restaurant's staff and factors that could be associated with these domains.Design/methodology/approach: A cross-sectional study involving 306 restaurant staff in Amman City, Jordan was conducted using a validated self-reported questionnaire. Logistic regression analysis was performed to identify factors independently associated with knowledge, attitude and practices (KAP).Findings: The results showed that most restaurant staff had moderate to excellent knowledge, positive attitudes, low to moderate risk practices regarding food allergy. Knowledge level was significantly associated with the staff's age, position, education level and restaurant class. Further, attitude level was significantly associated with staff age, experience, gender, education level, restaurant class and whether the restaurant held food safety certificates. Similarly, staff behavioral practices were significantly associated with staff position, restaurant class and the presence of valid food safety certificates.Practical implications: This study suggests that more training for the staff in restaurants would be associated with a lower risk of providing unsafe meals.Originality/value: This study demonstrated the need for the pre-employment theoretical and practical tests for restaurants’ staff to determine their knowledge level and provide them mandatory developing training programs to support and facilitate food allergy risk management and to develop food allergy policies.