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Background & objective(s) No meta-analysis is available on the effect of Nigella sativa (NS) on obesity indices. This systematic review and meta-analysis was conducted to systematically review the available Randomized Clinical Trials (RCTs) that examined the effects of NS on Body Weight (BW), Body Mass index (BMI), and Waist Circumference (WC) in adults. Methods Relevant articles published up to January 2018 were searched through PubMed/Medline, SCOPUS, Cochrane Library, and Google Scholar databases, using relevant keywords. All RCTs that examined the effect of NS supplementation on BW, BMI, or WC were included. Results Overall, thirteen RCTs, including 875 subjects (64% males) were included in this study. Combining effect sizes from ten studies, NS supplementation significantly reduced BW (Weighted Mean Differences (WMD): −1.76 kg, 95% CI: −3.34 to −0.17, I2 = 87.4%), as compared to placebo. Subgroup analysis by the intervention type (I2 = 0.0%), participants’ gender (I2 = 0.0%), and age (I2 = 5.5%) removed between-study heterogeneity. A significant reduction was seen in BMI (WMD: −0.85 kg/m2, 95% CI: −1.23, −0.46, I2 = 70.6%) after NS supplementation than placebo among eleven trials. Subgroup analysis based on study duration (I2 = 0.0%), participants’ gender (females: I2 = 0.0% & both genders: I2 = 20.9%), an age (I2 = 35.9%) disappeared the heterogeneity. However, no significant reduction was found in WC comparing NS supplementation to placebo (WMD: −4.04 cm, 95% CI: 11.37, 3.27, I2 = 97.8%) in five studies. Conclusions We find a significant effect of NS supplementation on BW and BMI in adults. However, the effect of NS supplementation on WC was not significant in this meta-analysis.

Background & objective(s) Obesity is a worldwide epidemic and a common medical condition associated with a variety of chronic diseases. Cereal beta-glucans are soluble fibers with potential health benefits. A number of randomized controlled trials (RCTs) have investigated the effect of cereal beta-glucan consumption on weight, but these results have not been summarized in a meta-analysis. The purpose of this study was to investigate the effect of cereal beta-glucan consumption on body weight, body mass index, waist circumference and a total energy intake. Methods Studies were identified using MEDLINE/PubMed, Scopus and Cochrane databases. Screening of relevant articles and references was carried out until December 2018. There were no language restrictions. This systematic review and meta-analysis was performed using the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results Twenty eligible studies were identified and analyzed. Our study found a significant reduction in body weight and body mass index (BMI) following beta-glucan consumption (weighted mean difference [WMD]: −0.77 kg, 95% CI: −1.49, −0.04) and (WMD: −0.62 kg/cm2, 95% CI: −1.04, −0.21), respectively. There was no significant effect on waist circumference and energy intake. A subgroup analysis showed that a beta-glucan dose of ≥ 4 g/day lead to an increase in energy intake. Conclusion The findings of this study indicates that cereal beta-glucan consumption seems to decrease body weight and BMI, but has no effect on waist circumference and energy intake.

Background & objective Effects of walnut intake on anthropometric measurements have been inconsistent among clinical studies. Thus, we conducted a meta-analysis of randomized clinical trials (RCTs) to evaluate and quantify the effects of walnut intake on anthropometric characteristics. Methods We carried out a systematic search of all available RCTs up to June 2019 in the following electronic databases: PubMed, Scopus, Web of Science and Google Scholar. Pooled weight mean difference (WMD) of the included studies was estimated using random-effects model. Results A total of 27 articles were included in this meta-analysis, with walnuts dosage ranging from 15 to 108 g/d for 2 wk to 2 y. Overall, interventions with walnut intake did not alter waist circumference (WC) (WMD: -0.193 cm, 95 % CI: -1.03, 0.64, p = 0.651), body weight (BW) (0.083 kg, 95 % CI: -0.032, 0.198, p = 0.159), body mass index (BMI) (WMD: -0.40 kg/m,295 % CI: -0.244, 0.164, p = 0.703), and fat mass (FM) (WMD: 0.28 %, 95 % CI: -0.49, 1.06, p = 0.476). Following dose-response evaluation, reduced BW (Coef.= -1.62, p = 0.001), BMI (Coef.= -1.24, p = 0.041) and WC (Coef.= -5.39, p = 0.038) were significantly observed through walnut intake up to 35 g/day. However, the number of studies can be limited as to the individual analysis of the measures through the dose-response fashion. Conclusions Overall, results from this meta-analysis suggest that interventions with walnut intake does not alter BW, BMI, FM, and WC. To date, there is no discernible evidence to support walnut intake for improving anthropometric indicators of weight loss.

Background Data about the effects of resistance exercise on level of IGF-1 in the serum are conflicting. To resolve this inconsistency, we performed a systematic review and meta-analysis to precisely examine the effects of resistance exercise on the levels of serum IGF-1. Methods PubMed, Scopus, Web of Science, and Embase databases were systematically searched from their inceptions until 10 December 2019 for randomized controlled trials (RCTs) comparing individuals who underwent resistance training and control participants. We applied a random-effects model to calculate the weighted mean difference (WMD). Results 33 trials reported IGF-1 level as an outcome measure. The pooled estimate demonstrated a significant increase in IGF-1 (WMD: 10.34 ng/ml, 95 % CI: 4.93, 15.74, p = 0.000, I2 = 90.3 %) after resistance training compared with the control group. Subgroup analysis demonstrated that the increase in IGF-1 levels following resistance training was only statistically significant in treatment duration ≤16 weeks (WMD: 8.04 ng/ml), participants aged more than 60 years old (WMD: 9.84 ng/ml); and in women (WMD: 17.27 ng/ml). Subsequent analysis of the relationship between participants’ age with plasma IGF-1 alterations revealed a U shape correlation in non-liner dose response, in which resistance training resulted in a declined IGF-1 level up to 40 years of age. Beyond 40 years old, the IGF-1 level was increased following resistance training. Conclusion We have successfully demonstrated that resistance training was associated with an increased IGF-1 level among those who received the training for ≤16 weeks, among participants older than 60 years old, and among women. Further studies are warranted to clarify the mechanisms underlying the influence of resistance training on IGF-1.

Objects Cardiovascular disease (CVD) is one of the leading causes of death worldwide. CVD is associated with increased levels of reactive oxygen species which are pro-inflammatory and can damage the endothelium. The pomegranate fruit is a rich source of phytochemicals with a high antioxidant and anti-inflammatory activity, possessing thus health benefits. This systematic review and meta-analysis aims to evaluate the effect of pomegranate juice on the biomarkers of inflammation and vascular dysfunction. Methods Studies were identified using the PubMed/Medline and SCOPUS databases. Screening of relevant articles and references was carried out from inception until May 2019. This systematic review and meta-analysis was performed using the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results Overall, 16 randomized controlled trials (RCTs) involving 572 subjects were included in this study. Combining effect sizes from 16 studies, we recorded that pomegranate supplementation significantly reduced hs-CRP, IL-6 and TNF-α (Weighted Mean Diff ;erences (WMD): −6.57 mg/L, 95 % CI: −10.04 to −3.10, P = 0.000; WMD: −1.68 pg/mL, 95 % CI: −3.52, 0.157, P = 0.000; WMD: −2.37 pg/mL, 95 % CI: −3.67, −1.07, P = 0.00, respectively) levels, when compared to placebo. No significant reduction was found in CRP (WMD: 2.19 mg/dL, 95 % CI: −3.28, 7.67, P = 0.61), E-selectin (WMD: 8.42 ng/mL, 95 % CI: −22.9, 39.8, P = 0.599), ICAM (WMD= −17.38 ng/mL, 95 % CI: −53.43, 18.66, P = 0.107), VCAM (WMD: −69.32 ng/mL, 95 % CI: −229.26, 90.61, P = 0.396) or MDA (WMD: 0.031 μmol/L, 95 % CI: −1.56, 0.218, P = 0.746) comparing pomegranate supplementation to placebo. Conclusion We found a significant effect of pomegranate supplementation on hs-CRP, IL-6 and TNF-α in adults. However, the effects of pomegranate supplementation on CRP, E-selectin, ICAM, VCAM or MDA were not significant in this meta-analysis.

Objective Glucose disorders and dyslipidemia are closely associated with obesity and metabolic disease. The purpose of this study was to investigate the effect of Carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and Insulin resistance. Method MEDLINE/PubMed, Scopus and Web of sciences were investigated to identify relevant articles up to June 2019. The search strategy combined the Medical Subject Heading and Title and/or abstract keywords. The combined effect sizes were calculated as weight mean difference (WMD) using the random-effects model. Between study heterogeneity was evaluated by the Cochran’s Q test and I2. Results Four RCTs studies investigated Carnosine use versus any control for at least 2 weeks were identified and analyzed. Overall results from the random-effects model on included studies, with 184 participants, indicated that carnosine intervention reduced HbA1C levels in intervention vs control groups (WMD: −0.92 %, 95 % CI: −1.20, −0.63, I2:69 %). Four studies, including a total of 183 participants, reported TG changes as an outcome measure variable, but combined results did not show significant reduction in this outcome (WMD: −14.46 mg/dl, 95 % CI: −29.11, 0.19, I2:94 %). Furthermore, combined results did not show any significant change in HOMA-IR, Cholesterol, fasting blood sugar, or HDL-C. Conclusion Carnosine supplementation results in a decrease in HbA1C, but elicits no effect on HOMA-IR, Cholesterol, fasting blood sugar, TG and HDL-C. Future studies with a larger sample sizes, varied doses of carnosine, and population-specific sub-groups are warranted to confirm, and enhance, the veracity of our findings.