The effects of green coffee extract supplementation on glycemic indices and lipid profile in adults: a systematic review and dose-response meta-analysis of clinical trials.

BACKGROUND: The role of coffee consumption in the risk of cardiovascular diseases has been debated for many years. The current study aimed to summarize earlier evidence on the effects of green coffee extract (GCE) supplementation on glycemic indices and lipid profile. METHODS: We searched available online databases for relevant clinical trials published up to October 2019. All clinical trials investigating the effect of GCE supplementation, compared with a control group, on fasting blood glucose (FBG), serum insulin, total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were included. Overall, 14 clinical trials with a total sample size of 766 participants were included in the current meta-analysis. RESULTS: We found a significant reducing effect of GCE supplementation on FBG (weighted mean difference (WMD): -2.35, 95% CI: - 3.78, - 0.92 mg/dL, P = 0.001) and serum insulin (WMD: -0.63, 95% CI: - 1.11, - 0.15 µU/L, P = 0.01). With regard to lipid profile, we observed a significant reduction only in serum levels of TC following GCE supplementation in the overall meta-analysis (WMD: -4.51, 95% CI: - 8.39, - 0.64, P = 0.02). However, subgroup analysis showed a significant reduction in serum TG in studies enrolled both genders. Also, such a significant reduction was seen in serum levels of LDL and HDL when the analyses confined to studies with intervention duration of ≥8 weeks and those included female subjects. In the non-linear dose-response analyses, we found that the effects of chlorogenic acid (CGA) dosage, the main polyphenol in GCE, on FBG, TG and HDL were in the non-linear fashions. CONCLUSION: In conclusion, we found that GCE supplementation improved FBG and serum levels of insulin and TC. Also, there was a significant improvement in other markers of lipid profile in some subgroups of clinical trials.

The effect of green coffee extract supplementation on anthropometric measures in adults: A comprehensive systematic review and dose-response meta-analysis of randomized clinical trials.

BACKGROUND AND AIM: Two meta-analyses summarized data on the effects of green coffee extract (GCE) supplementation on anthropometric measures. However, the accuracy of those meta-analyses is uncertain due to several methodological limitations. Therefore, we aimed to conduct a comprehensive systematic review and dose-response meta-analysis to summarize all available evidence on the effects of GCE supplementation on anthropometric measures by considering the main limitations in the previous meta-analyses. METHODS: We searched available online databases for relevant publications up to January 2020, using relevant keywords. All randomized clinical trials (RCTs) investigating the effects of GCE supplementation, compared with a control group, on anthropometric measures [including body weight, body mass index (BMI), body fat percentage, waist circumference (WC) and waist-to-hip ratio (WHR)] were included. RESULTS: After identifying 1871 studies from our initial search, 15 RCTs with a total sample size of 897 participants were included in the systematic review and meta-analysis. We found a significant reducing effect of GCE supplementation on body weight (weighted mean difference (WMD): -1.23, 95 % CI: -1.64, -0.82 kg,P < 0.001), BMI (WMD: -0.48, 95 % CI: -0.78, -0.18 kg/m2, P = 0.001), and WC (WMD: -1.00, 95 % CI: -1.70, -0.29 cm, P = 0.006). No significant effect of GCE supplementation on body fat percentage and WHR was seen. In the dose-response analyses, there was no significant association between chlorogenic acid (CGA) dosage, as the main polyphenol in green coffee, and changes in anthropometric measures. CONCLUSION: We found that GCE supplementation had a beneficial effect on body weight, BMI and WC. It provides a cost-effective and safe alternative for the treatment of obesity. Additional well-designed studies are required to further confirm our findings.

Effects of zinc supplementation on lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND AIM: Findings on the effects of zinc supplementation on the lipid profile in patients with type 2 diabetes mellitus (T2DM) are conflicting. The current comprehensive systematic review and meta-analysis aimed to summarize available evidence in this regard. METHODS AND RESULTS: After a systematic search in the online databases, we included the randomized controlled trials (RCTs) investigating the effect of zinc supplementation on lipid profile [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG)] in patients with T2DM. Altogether, 9 studies with a total sample size of 424 patients with T2DM were included in the analysis. Combining 9 effect sizes from 9 RCTs, we found a significant lowering effect of zinc supplementation on serum levels of TG (weighted mean difference (WMD): -17.08, 95% CI: -30.59, -3.58 mg/dL, P = 0.01) and TC (WMD: -26.16, 95% CI: -49.69, -2.62 mg/dL, P = 0.02). Although the overall effect of zinc supplementation on LDL-C levels was not significant, a beneficial effect was seen in studies that administered <100 mg/d zinc. Based on the non-linear dose-response analysis, a greater reduction in serum levels of TC and LDL-C following zinc supplementation was seen at <12 weeks' duration of intervention. Unlike the overall effect size, we found a significant increasing effect of zinc supplementation on serum HDL-C concentrations in most subgroups of RCTs according to the subgroup analyses. CONCLUSION: We found that zinc supplementation may beneficially influence lipid profile in patients with T2DM.

Effects of consuming date fruits (Phoenix dactylifera Linn) on gestation, labor, and delivery: An updated systematic review and meta-analysis of clinical trials.

BACKGROUND: Recent studies have shown that consumption of date fruits during pregnancy and also postpartum period might affect some pregnancy outcomes. We performed an updated systematic review and meta-analysis about the effects of consuming date fruits on gestation, labor, and delivery. METHODS: Two researchers independently searched the online databases of PubMed, Scopus, Web of Science, Embase, Google Scholar, and EBSCO up to January 2019 for clinical trials examining the effects of date fruits consumption on any types of gestation, labor, and delivery outcomes. A fixed-effects model or random-effects models were applied to pool data, where appropriate. Quality assessment was done by Jadad scale. RESULTS: In total, 11 and 8 studies were included in the systematic review and meta-analysis. Meta-analysis revealed that date fruit consumption significantly reduced gestation duration (pooled effect size: -0.30, 95% CI: -0.45, -0.15; P < 0.001), increased cervical dilation on admission (pooled effect size: 0.94, 95% CI: 0.88, 1.00; P < 0.001), and shorten duration of first stage of labor (pooled effect size: -50.09, 95% CI: -72.25, -27.93; P < 0.001). Also, it was revealed that date fruit consumption significantly reduced duration of second stage of labor in fixed-effects model (pooled effect size: -9.85, 95% CI: -14.00, -5.70; P < 0.001); however, this effect was not significant in random-effects analysis (pooled effect size: -11.27, 95% CI: -28.23, -5.68; P = 0.193). CONCLUSIONS: Date fruits intake seems to reduce gestation duration and duration of the first stage of labor, and also increase cervical dilation on admission.

Dietary intake of fish, n-3 polyunsaturated fatty acids and risk of hip fracture: A systematic review and meta-analysis on observational studies.

Previous studies have shown that fish consumption and dietary intake of n-3 polyunsaturated fatty acids (n-3 PUFAs) are associated with hip fracture; however, findings were conflicting. The present review aimed to summarize the current evidence on the association of fish consumption and dietary intake of n-3 PUFAs with hip fracture. The online databases of PubMed, ISI Web of Science, Scopus, ProQuest, Science Direct and Embase were searched until August 2017 for related publications using relevant keywords. To pool data, either a fixed-effects model or random-effects models were used. Cochran's Q tests were used to assess heterogeneity between studies. In total, 10 studies (7 prospective and 3 case-control studies) were included in this systematic review, and 9 studies with total sample size of 292657 participants were included in the meta-analysis. The age of participants was 20 years or older. Combining 8 effect sizes from 4 prospective studies and 2 case-control studies revealed a significant inverse association between fish consumption and risk of hip fracture (pooled effect size: 0.88, 95% CI: 0.79-0.98, P = 0.02). Although this relationship became non-significant in prospective studies, a significant inverse association was found in prospective studies with sample size of 10000 individuals or more, and studies that considered body mass index as a covariate. Furthermore, dietary intake of n-3 PUFAs was inversely associated with risk of hip fracture (pooled effect size: 0.89, 95% CI: 0.80-0.99, P = 0.02). Also, such relationship was seen after excluding one case-control study and combining effect sizes only from prospective studies (pooled effect size: 0.88, 95% CI: 0.80-0.98, P = 0.02). In conclusion, we found that fish consumption and dietary intake of n-3 PUFAs might have protective effects on bone health and decline the risk of hip fracture.

Estimation of iron deficiency anemia in Iranian children and adolescents: a systematic review and meta-analysis.

OBJECTIVES: Iron deficiency anemia (IDA) is a major health issue in those aged less than 18 years old with high impact on their development. There are several reports from Iran with variable results. Systematic review and met analysis of these data would reveal a more realistic view of the prevalence of iron deficiency (ID). METHODS: We conducted a systematic search of national and international databases from December 1990 to 31 January 2016 for population-based studies providing estimates on the prevalence of IDA in Iran. From the extracted crude prevalence rates, the heterogenic index of the studies was determined using the Cochran's test (Q) and I2. Then, based on the heterogenetic results, a random effects model for estimate pooled prevalence of IDA was used. Meta-regression was applied to determine heterogeneity suspected factors. RESULTS: The overall prevalence of IDA in Iranian population with age less than 18 years was estimated to be 13.9% (95% CI: 10.8-17.1) and the overall prevalence of ID was 26.9% (95% CI: 19.7-34.1). The prevalence of IDA was 7.9% (95% CI: 4.1-11.7) in males and 8.5% (95% CI: 6.1-10.8) among females aged under than 18 years. DISCUSSION: Despite the efforts of ministry of health and medical education of Iran in implementing free iron supplements for infants and for girls, the prevalence of ID and resultant anemia is considerable. Further interventions to increase use of supplements when they are provided and special programs for non-covered groups including boys under six are in great need.

Estimating the Completeness of Lung Cancer Registry in Ardabil, Iran with a Three-Source Capture-Recapture Method.

Cancer registration is an important component of a comprehensive cancer control program, providing timely data and information for research and administrative use. Capture-recapture methods have been used as tools to investigate completeness of cancer registry data. This study aimed to estimate the completeness of lung cancer cases registered in Ardabil Population Based Cancer Registry (APBCR) with a three-source capture-recapture method. Data for all new cases of lung cancer reported by three sources (pathology reports, death certificates, and medical records) to APBCR for 2006 and 2008 were obtained. Duplicate cases shared among the three sources were identified based on similarity of first name, last name and father's names. A log-linear model was used to estimate number of missed cases and to control for dependency among sources. A total of 218 new cases of lung cancer was reported by three sources after removing duplicates. The estimated completeness calculated by log-linear method was 26.4 for 2006 and 27.1 for 2008. The completeness differed according to gender. In men, the completeness was 26.0% for 2006 and 28.1 for 2008. In women, the completeness was 36.5% for 2006 and 46.9 for 2008. In conclusion, none of the three sources can be considered as a reliable source for accurate cancer incidence estimation.