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Background : In the present meta-analysis, we aimed to summarize the relationship between dietary total antioxidant capacity (TAC), general and central obesity indices and lipid profile in adult population. Methods : The electronic databases of Web of Sciences, PubMed, Scopus and Cochrane library were searched for relevant studies from inception to October 2019. The effect size was indicated as weighted mean difference (WMD) and 95% confidence intervals (CI) by using random effects model. The I 2 index and Cochran's Q-test were used for evaluating heterogeneity. Results : From 2,469 studies identified, thirty-four studies (nineteen cross-sectional studies, thirteen cohort studies, two case-control studies) were included in the meta-analysis. According to our results, higher categories of TAC were associated with significantly lower serum triglyceride concentartions (TG; WMD: -7.58; CI: -11.42, -3.75; P < 0.001) and waist circumference (WC; WMD: -1.17; 95% CI: -1.47, -0.87; P < 0.001); while no significant change in body mass index (BMI; WMD: -0.17; 95% CI: -0.35, 0.01; P = 0.12), high density lipoprotein cholesterol (HDL-C; WMD: 0.61; 95% CI: -0.16, 1.40; P = 0.12), low density lipoprotein cholesterol (LDL-C; WMD: 1.34; 95% CI: -0.61, 3.30; P = 0.17) and total cholesterol (TC; WMD: 1.19; 95% CI: -1.46, 3.855; P = 0.37) was reported. Conclusion : Higher dietary TAC was related to reduced prevalence of central obesity, reduced WC and TG concentrations in the current meta-analysis. Moreover, subgroup analysis showed that TAC measurement index, geographical area, dietary assessment tool, health status and gender were potential sources of heterogeneity.

Objectives: We aimed to evaluate the possible role of dietray TAC against different types of cancers in a systematic review and meta-analyses of observational studies. Methods: A literature search of authentic electronic resources had been performed to obtain the relevant studies up to February 2020. Results: Twenty-one studies including nine prospective and twelve case-control studies were included in the current systematic review and meta-analysis. These studies have included 1404297 individuals. Higher TAC categories were associated with 21% reduced risk of colorectal cancer, 27% reduced risk of endometrial cancer, 42% reduced risk of gastric cancer, and 32% reduced risk of pancreatic cancer. In meta-analysis of prospective studies also highest category of TAC was associated with reduced incidence of breast cancer (RR= 0.68; CI: 0.54, 0.86; P  = 0.025), colon cancer (RR= 0.92; CI: 0.74, 1.16; P  = 0.01), hepatocellular carcinoma (RR= 0.49; CI: 0.35, 0.69; P  < 0.001), gastric cancer (RR= 0.65; CI: 0.50, 0.84; P  = 0.001), lung cancer (RR= 0.90; CI: 0.85, 0.95; P  = 0.001) while increased risk of rectal cancer (RR= 1.02; CI: 0.69, 1.52; P  = 0.005). Conclusion: Higher intake of dietary TAC was in association with reduced risk of different types of cancers in meta-analysis of observational studies.

Background: There are numerous trials reported the effect of alpha-lipoic acid (ALA) on obesity measurements; while no summarised dose-response meta-analysis is available to address the effects of dose and duration of ALA supplementation on obesity measurements. We aimed to summarise the results of studies evaluating the effects of ALA supplementation on obesity measurements in a systematic review and dose-response meta-analysis., Methods and Materials: In a systematic search from Scopus, PubMed, Embase, Proquest electronic databases up to January 2020 relevant studies were retrieved. Randomised, placebo-controlled trials investigating the effect of ALA supplementation on obesity measurements including weight, body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and fat mass (FM) were included. Two class and dose-response meta-analysis were performed to data analysis., Results: Totally, 18, 21 and 8 studies were included for the meta-analysis of ALA-weight, ALA-BMI, ALA-WC, respectively. In the two-class meta-analysis, ALA treatment significantly reduced weight (WMD: -2.29 kg, 95% CI: -2.98, 1.60, P < .01) and BMI (WMD: -0.49 kg/m 2 , 95% CI:-0.83,-0.15, P = .005) but no effect on WC (WMD: -2.57 cm, 95% CI: -8.91, 3.76; P = .426). While the dose-response meta-analysis revealed that the duration of ALA treatment is a significant factor affecting WC reduction (P non-linearity  = .047). While no evidence of departure from linearity was observed for other variables; moreover, subgrouping also revealed that gender could be an important factor affecting the ALA impact on WC which was significant among women (WMD: -4.099; CI: -7.837, -0.361; P = .032)., Conclusion: According to our finding, ALA treatment significantly reduced BMI, weight in a two-class meta-analysis without evidence of departure from linearity in terms of dose or duration. While the association of ALA treatment on WC is dependent to the duration of the study. Although further trials evaluating the other obesity measurements specially central obesity will be helpful to infer a more reliable result., (© 2020 John Wiley & Sons Ltd.)