Effects of chocolate on cognitive function in healthy adults: A systematic review and meta-analysis on clinical trials.

Cognitive function is defined as performance in objective tasks that need conscious mind effort. It has been shown that consuming foods rich in flavanols causes neurobiological effects and improves learning, memory, and global cognitive function. This study aimed to investigate the impact of chronic chocolate consumption on cognitive function in healthy adults based on published trials. The PICO strategy was applied to examine the research question in this study. Researchers searched the Web of Science, Science Direct, Pubmed, Scopus, Cochrane Library, and Google Scholar databases. Related articles of randomized controlled trials that evaluated the chronic effect of chocolate on cognitive function were selected (all published from their inception to February 2021). The difference in means of the last and first measurements was the main effect measure between the control and intervention groups. For quantitative data synthesis, weighted mean difference (WMD) and 95% confidence interval (CI) were performed in the random effect model. Of the initial 340 articles identified, seven trials met the eligibility criteria. Chronic chocolate intake significantly reduced executive function time (WMD: -11.77, 95% CI: -22.49, -1.05, p = 0.03) of the participants. Further, the language and executive function (WMD: 6.38, 95% CI: 5.97, 6.80, p < 0.001) was raised by 6.38 times after the intervention with chocolate. We could not perform subgroup analysis due to insufficient trials and significant heterogeneity in some studies. It is concluded that daily consumption of cocoa may provide short and middle-term effects on young adults and make them better cognitive performance in learning, memory, and attention.

The effect of melatonin supplementation on liver indices in patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis of randomized clinical trials.

Several randomized clinical trials (RCTs) evaluated the effect of melatonin supplementation on liver enzymes in patients with non-alcoholic fatty liver disease (NAFLD) and reported conflicting results. To meet these discrepancies, a meta-analysis was conducted to evaluate the eff ;ect of melatonin on liver indices in patients with NAFLD. To collect the required data, a thorough search was conducted through Web of science, Pubmed, Cochrane database, Embase, Google Scholar, ProQuest, and Scopus databases. The aim was to find clinical trials over the effect of melatonin supplementation on liver indices up to 16 May 2019. As a result, five eligible articles were selected and analysed in this meta-analysis using a fixed-effects model. Heterogeneity test was performed by I2 statistics and Cochrane Q test. The results showed that melatonin had a significant effect on aspartate aminoteransferase (AST) (WMD = 2.29, [95 %CI: 1.14, 3.43] IU/L, p = <0.001), alkaline phosphatase (ALP) (WMD = -8.40, [95 %CI -11.33, -5.48] IU/L, p < 0.001), and gamma-glutamyltransferase (GGT) (WMD = -33.37, [95 %CI: -37.24, -29.49] IU/L, p= < 0.001). Melatonin had no significant effect on alanine aminotransferase (ALT) regarding the overall effect size. Based on this meta-analysis, melatonin supplementation can improve liver indices. However, more RCTs are required with larger sample sizes and better control of confounding variables such as weight, body mass index, and gender to determine the effect of melatonin on patients with non-alcoholic fatty acid disease.

The effects of soy isoflavones on total testosterone and follicle-stimulating hormone levels in women with polycystic ovary syndrome: a systematic review and meta-analysis.

OBJECTIVES: The aims of this systematic review and meta-analysis were to evaluate the effectiveness of soy isoflavones on serum levels of total testosterone (TT) and follicle-stimulating hormone (FSH) in women with polycystic ovary syndrome (PCOS). METHODS: A meta-analysis was performed by searching for relevant randomised controlled trials (RCTs) in several databases. Of the four trials found, the eligibility criteria to evaluate the efficacy of soy isoflavones on serum levels of FSH were met by three trials and of TT by four trials. The Cochrane scale was used to evaluate the risk of bias. Fixed-effects and random-effects models were used to evaluate overall effect. The χ 2 test (Cochran's Q test) and the I 2 index were used to assess the heterogeneity of RCTs. RESULTS: Our results showed that soy isoflavones significantly decreased TT (weighted mean difference [WMD] - 0.14; 95% confidence interval [CI] - 0.2, -0.02; p = 0.016; I 2 = 89%, p < 0.001) but had no significant effect on FSH levels (WMD -0.25; 95% CI -0.54, 0.02; p = 0.06; I 2 = 0%, p = 0.85). CONCLUSION: Although the results of this meta-analysis showed that soy isoflavones in women with PCOS decreased TT and had no significant effect on FSH, better and more valid studies are needed to confirm these results.

Combined cranberry supplementation and weight loss diet in non-alcoholic fatty liver disease: a double-blind placebo-controlled randomized clinical trial.

A double-blind placebo-controlled randomised clinical trial was conducted on 41 patients with non-alcoholic fatty liver disease (NAFLD). Participants were randomly allocated to receive either a cranberry supplement or a placebo for 12 weeks. Both groups were assigned to follow a weight loss diet. At the end of the study, alanine aminotransferase and insulin decreased significantly in both groups (p < .05); however, this reduction was significantly greater in the cranberry group than in the placebo group (p < .05). Significant improvements in insulin resistance were observed in the cranberry group and between the two groups (p < .001 and p = .020, respectively). Also, there was an improvement in steatosis grade and anthropometric measurements in both groups (p < .05), and there was no significant difference between the two groups in regard to these factors (p > .05). It seems that 288 mg of cranberry extract might improve managing NAFLD, which is equivalent to 26 g of dried cranberry.

Effect of fenugreek extract supplement on testosterone levels in male: A meta-analysis of clinical trials.

Different types of glycosides extract of fenugreek have shown androgenic and anabolic effect in male. The aim of the study was to evaluate the effect of fenugreek extract on total testosterone levels in male. Medline via PubMed, Scopus databases, Cochrane Library, Web of Science, and Google Scholar were searched up to November 2018 for randomized clinical trials comparing intake of fenugreek extract with control group. Data on change in serum total testosterone were pooled using random-effects models. A total of four trials were included. Fenugreek extract has a significant effect on total serum testosterone. Results from clinical trials suggest that fenugreek extract supplement has an effect on serum total testosterone levels in male.

Impact of resveratrol supplementation on inflammatory, antioxidant, and periodontal markers in type 2 diabetic patients with chronic periodontitis.

BACKGROUND: Diabetes mellitus and periodontal disease are two common and chronic diseases with bidirectional relationship influence public health and quality of life. The aims of this study was to study the impact of resveratrol supplementation in adjunct with non-surgical periodontal therapy on inflammatory, antioxidant, and periodontal markers in patients with type 2 diabetes with periodontal disease. MATERIALS AND METHODS: In this randomized clinical trial, 43 patients with diabetes and chronic periodontitis were randomly allocated into two intervention and control groups receiving either resveratrol supplements or placebo for 4 weeks. Serum levels of interleukin 6 (IL6), tumor necrosis factor α (TNFα), total antioxidant capacity (TAC) and clinical attachment loss (CAL) as the main index of periodontal marker were measured pre-intervention and post-intervention. RESULTS: In the intervention group, the mean serum level of IL6 was reduced significantly (P = 0.039) post-intervention (2.19 ±â€¯1.09 and 1.58 ±â€¯1.06). No significant differences were seen in the mean levels of IL6, TNFα, TAC and CAL between two groups post-intervention. CONCLUSIONS: It is suggested that daily consumption of resveratrol supplement may not change TNFα, TAC and CAL, but it would be beneficial in reducing serum levels of IL6. Therefore, further studies are suggested to investigate the effects of resveratrol supplementation along with NST on periodontal status.

The Impact of Resveratrol Supplementation on Blood Glucose, Insulin, Insulin Resistance, Triglyceride, and Periodontal Markers in Type 2 Diabetic Patients with Chronic Periodontitis.

The aim of this study was to investigate the impact of resveratrol supplementation along with non-surgical periodontal treatment on blood glucose, insulin, insulin resistance, triglyceride (TG), and periodontal markers in patients with type 2 diabetes with periodontal disease. In this double-blind clinical trial study, 43 patients with diabetes with chronic periodontitis were participated. Subjects were randomly allocated to intervention and control groups. The intervention and control groups received either 480 mg/day of resveratrol or placebo capsules (two pills) for 4 weeks. Fasting blood glucose, insulin, insulin resistance (homeostasis model assessment of insulin resistance), TGs, and pocket depth were measured in all subjects' pre-intervention and post-intervention. The mean serum levels of fasting insulin and insulin resistance (homeostasis model assessment of insulin resistance) were significantly lower in the intervention group compared with control group (10.42 ± 0.28 and 10.92 ± 0.9; 3.66 ± 0.97 and 4.49 ± 1.56, respectively). There was a significant difference in the mean pocket depth between intervention and control groups (2.35 ± 0.6 and 3.38 ± 0.5, respectively) following intervention. No significant differences were observed in the mean levels of fasting blood glucose and TGs between two groups' post-intervention. It is recommended that resveratrol supplementation may be beneficial as adjuvant therapy along with non-surgical periodontal treatment in insulin resistance and improving periodontal status among patients with diabetes with periodontal disease. Copyright © 2016 John Wiley & Sons, Ltd.