Dietary Patterns in Association with Sleep Duration in Iranian Adults: Results from YaHS-TAMYZ and Shahadieh Cohort Studies.

Background: Little observational studies have been conducted on the association between diet and sleep. We conducted a cross-sectional study to evaluate the associations of dietary patterns with sleep duration in an Iranian population. Methods: This study was conducted on the baseline data of two population-based Iranian cohorts: the YaHS-TAMYS and Shahedieh studies. Dietary intakes were assessed in 10451 Yazdi people aged 20-75 years. Dietary habits were derived from answers to a food frequency questionnaire, and a factor analysis using principal component analysis (PCA) was used to identify dietary patterns. The reported sleep duration was categorized as short (<6 h), normal (6-8 h) or long (>8 h). Multivariable logistic regression was used to determine the relationship between dietary patterns and the odds of short and long sleep duration. Results: Four major dietary patterns were identified: "healthy," "western," "traditional," and "high-carbohydrate, high-fat." In the Shahedieh study, participants in the top quartile of the western dietary pattern had greater odds of short (<6 h) and long (>8 h) sleep duration (OR = 1.49; 95% CI: 1.17, 1.90; P trend <0.001 and OR = 1.46; 95% CI: 1.12, 1.90; P trend = 0.014, respectively) than those in the bottom quartile. Also, participants in the highest quartile of the high-carbohydrate, high-fat pattern had higher odds of long sleep duration compared with those in the lowest quartile (OR = 1.36; 95% CI: 1.05, 1.75; P trend = 0.005). Pooling the two studies revealed that the western dietary pattern was significantly associated with short sleep duration (OR = 1.31; 95% CI: 1.08, 1.59). Conclusions: The western dietary pattern might inversely be associated with sleep duration. Future prospective studies are recommended to confirm these results.

Dietary glycemic index and glycemic load in association with sleep duration: YaHS-TAMYZ and Shahedieh observational studies.

BACKGROUND & AIMS: Current data on the association between dietary glycemic index (GI) and glycemic load (GL) and sleep duration are limited and controversial. The present cross-sectional study aimed to investigate the relationship between dietary GI and GL with sleep duration in a large number of adults living in central Iran. METHODS: Baseline data from two Iranian cohorts were pooled for the current analysis: the YaHS-TAMYZ (n = 9962) and Shahedieh (n = 9977) studies. Demographic data as well as dietary intakes, sleep duration, and possible confounders, were collected by interview. Anthropometric measurements were also conducted by trained interviewers. Participants were categorized based on sleep duration [short (<6 h), normal (6-8 h), and long (>8 h)]. Multivariable logistic regression was used to determine the relationship between dietary GI/GL and the likelihood of short and long sleep duration. RESULTS: In total, 10,451 participants aged 20-70 years were included in the analyses. After controlling for all possible confounders, no significant association was observed between dietary GI and short or long sleep duration (P > 0.05). Individuals in the highest quartile of dietary GL had a higher chance for long sleep duration compared to participants in the lowest quartile (OR = 1.41; 95% CI: 1.14, 1.74, Ptrend = 0.001). No significant association was observed between dietary GL and short sleep duration. CONCLUSION: Dietary GL is positively associated with the likelihood of long sleep duration. Future prospective studies are required to confirm the current findings.

The healthy Nordic dietary pattern has no effect on inflammatory markers: A systematic review and meta-analysis of randomized controlled clinical trials.

OBJECTIVES: The Nordic diet (ND) is regarded as a healthy dietary pattern that might beneficially affect systemic chronic inflammation; however, the results of published studies are conflicting. The present systematic review and meta-analysis aimed to summarize the published evidence by randomized controlled clinical trials with regard to the effect of the ND pattern on circulating inflammatory markers such as C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). METHODS: PubMed, ISI Web of Science, Scopus, and Google Scholar were searched up to October 2017 to identify relevant studies. The risk of bias in the included studies was assessed using Cochrane's collaboration tool. The overall effects were calculated using the random effects model. RESULTS: Seven studies were eligible to be included in the systematic review. All studies were conducted in Nordic countries. The meta-analysis of six eligible clinical trials included 613 adult participants and showed that adherence to the ND does not significantly affect circulating CRP levels (weighted mean difference [WMD]: -0.17 mg/L; 95% confidence interval [CI], -0.69 to 0.35; P = 0.529). The meta-analysis of three studies that reported on the effect on other inflammatory makers also failed to find any significant effect on TNF-α (WMD: 0.23 mg/L; 95% CI, -0.75 to 1.21; P = 0.645) and IL-6 (WMD: 0.13 mg/L, 95% CI, -0.29 to 0.56; P = 0.539) concentrations. CONCLUSIONS: Adherence to the ND pattern does not seem to affect circulating CRP, IL-6, and TNF-α levels. Clinical trials with longer follow-up periods and including participants in other regions are highly recommended.

The Dietary Approaches to Stop Hypertension (DASH)-Style Diet and an Alternative Mediterranean Diet are Differently Associated with Serum Inflammatory Markers in Female Adults.

BACKGROUND: Studies on the association between a priori dietary patterns and serum highly sensitive C-reactive protein (hs-CRP) have led to inconsistent results, and we are not aware of any study on interleukin 17A (IL-17A) as an inflammatory marker associated with autoimmune diseases. OBJECTIVE: The present study aimed to investigate the association between Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean dietary patterns with circulating hs-CRP and IL-17A levels. METHODS: In this cross-sectional study, female teachers (aged 20-50 years) who lived in Yazd, Iran, were randomly selected from elementary, guidance, and high schools from September 2015 to February 2016. Anthropometric data, as well as general information and dietary food intakes, were gathered, and each participant gave 1 blood sample. Participants were categorized into tertiles based on the DASH and the Mediterranean diet calculated scores. The associations between the dietary patterns and serum hs-CRP and IL-17A levels were assessed in the crude and multivariable models. In total, 320 female teachers aged 40.38 (8.08) years were included. RESULTS: The DASH diet was associated with lower serum hs-CRP levels in the crude ( P = .05) and the fully adjusted models ( P = .02), while it was not significantly associated with IL-17A levels. The participants with the highest adherence to the Mediterranean diet had significantly lower circulating IL-17A levels ( P = .04) even controlling for all confounders ( P = .02); however, there was not a significant relationship between this diet and hs-CRP levels. CONCLUSIONS: The DASH and the Mediterranean dietary patterns might be differently associated with inflammatory markers. Further prospective studies are recommended to confirm our results.

Comparison of Serum Zinc Levels among Children with Simple Febrile Seizure and Control Group: A Systematic Review.

OBJECTIVE: Several factors are involved in the etiology of febrile seizure (FS), among them is zinc (Zn), which has been discussed in various studies. The present systematic review compares Zn levels in children with FS and a control group. MATERIALS & METHODS: We searched keywords of febrile seizure, febrile convulsion, children, childhood, fever, trace elements, risk factor, predisposing, zinc, Zn, and epilepsy in the following databases: SCOPUS, PubMed, and Google Scholar. The quality of research papers was assessed using a checklist. Data was extracted from primary studies based on demographic variables and amounts of Zn in case and control groups. RESULTS: Twenty primary studies were entered in the present study. Of which, eighteen studies, reported that Zn serum levels were significantly lower in the case group (patients with FS) than the control group. CONCLUSION: The present systematic review indicated that Zn is one factor for predicting FS. A low level of this element among children can be regarded as a contributing factor for FS, a conclusion with a high consensus among different studies carried out in different parts of the world.