The effect of almond intake on glycemic control: A systematic review and dose-response meta-analysis of randomized controlled trials.

Number trials have evaluated the effect of almond intake on glycemic control in adults; however, the results remain equivocal. Therefore, the present meta-analysis aims to examine the effectiveness of almond intake on glycemic parameters. Online databases including PubMed, Scopus, ISI web of science, Embase, and Cochrane Library were searched up to August 2021 for trials that examined the effect of almond intake on glycemic control parameters including fasting blood sugar (FBS), insulin, HOMA-IR, and HbA1C. Treatment effects were expressed as mean difference (MD) and the standard deviation (SD) of outcomes. To estimate the overall effect of almond intake, we used the random-effects model. In total, 24 studies with 31 arms were included in our analysis. The meta-analysis revealed that almond intake did not significantly change the concentrations of FBS, HbA1c, insulin levels, and HOMA-IR. In conclusion, there is currently no convincing evidence that almonds have a clear beneficial effect on glycemic control. Future studies are needed before any confirmed conclusion could be drowned.

Effects of grape products on inflammation and oxidative stress: A systematic review and meta-analysis of randomized controlled trials.

This systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted to determine the effects of grapes and grape products on inflammation and oxidative stress among adults. PubMed, Scopus, ISI Web of Science, and Cochrane Library databases were searched up to July 2020 to identify RCTs investigating the effects of grape and grape products on inflammatory and oxidative stress markers. Weighted mean differences (WMD) were pooled using a random-effects model. Of the 8,962 identified studies, 24 RCTs (27 arms) were included in the statistical analysis. Grape products significantly reduced serum C-reactive protein (CRP) levels (WMD: -0.35 mg/L; 95% CI: -0.62, -0.09, p = .008), but they had no significant effect on serum tumor necrosis factor-alpha (TNF-α) (WMD = -1.08 pg/ml; 95% CI: -2.29, 0.11, p = .07), interleukin-6 (IL-6) (WMD = 0.13 pg/ml; 95% CI: -0.35, 0.60, p = .60), total antioxidant capacity (TAC) (WMD = 0.15; 95% CI: -0.35, 0.65, p = .54), or malondialdehyde (MDA) (WMD = 0.14; 95% CI: -0.64, 0.92, p = .72). The analysis indicated possible decreasing effects of grapes and grape products on CRP, but they might not be able to change IL-6, TNF-α, TAC, and MDA concentrations. Nonetheless, further studies are warranted before definitive conclusions may be reached.

The effect of grapes/grape products on glycemic response: A systematic review and meta-analysis of randomized controlled trials.

The aim of this study was to perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to examine the effect of grapes/grape products supplementation on glycemic indices in adults. Our systematic search to find relevant RCTs was performed up to February 2020 using PubMed, Scopus, ISI Web of Science, Cochrane Library, and Google Scholar. Based on the heterogeneity between included studies, a random effects or a fixed model was applied in the meta-analysis, and results were expressed as weighted mean differences (WMD) with 95% confidence intervals (CI). Twenty-nine clinical trials (1,297 participants) fulfilled the eligibility criteria of the present meta-analysis. Overall, the grapes/grape products supplementation significantly reduced homeostatic model assessment of insulin resistance (HOMA-IR) (WMD: -0.54, 95% CI: -0.91, -0.17, p = . 004) but did not affect fasting insulin levels (WMD: -0.90 µIU/ml, 95% CI: -1.04, 2.84, p = .362) and hemoglobin A1C (Hb1Ac) percentage (WMD: 0.00%, 95% CI: -0.10, 0.11, p = . 916) in the main analyses. In addition, changes to fasting blood glucose (FBG) levels were in favor of the control group (WMD: 1.19 mg/dl, 95% CI: 0.05, 2.34, p = .041). We found that giving grapes/grape products to adults might have beneficial effects on the HOMA-IR. Further, large-scale RCTs with longer duration are required to confirm these results.

The effect of almond intake on lipid profile: a systematic review and meta-analysis of randomized controlled trials.

A number of clinical trials have examined the effect of almond intake on lipid profile in recent years; however, the results remain equivocal. Therefore, the present study aims to summarize and quantitatively examine the available evidence on the effectiveness of almond intake on lipid parameters by employing a systematic review and meta-analytic approach. Online databases including PubMed, Scopus, Embase, and Cochrane Library were searched up to September 2020 for randomized controlled trials that examined the effect of almond intake on lipid profile in adults. Treatment effects were expressed as weighted mean difference (WMD) and the corresponding standard error (SE) in the concentrations of serum lipids. To estimate the overall effect of almond intake, we employed the random-effect model. In total, 27 studies with 36 effect sizes were included in our analysis (1154 cases and 904 control subjects). The meta-analysis revealed that almond intake significantly changed the concentrations of triglycerides (WMD = -6.68 mg dL-1; 95% CI: -11.62, -1.75, p = 0.008), total cholesterol (WMD = -4.92 mg dL-1; 95% CI: -7.81, -2.03, p = 0.001), and low-density lipoproteins (WMD = -5.65 mg dL-1; 95% CI: -8.75, -2.55, p < 0.001); however it did not have a significant effect on high-density lipoprotein (WMD = -0.21 mg dL-1; 95% CI: -1.26, 0.84, p = 0.697) levels. Meta-regression analysis indicated a linear relationship between the dose of almond and change in TG (P = 0.021). This meta-analysis concludes that almond intake can significantly reduce lipid parameters. To draw straightforward conclusions regarding generalized recommendations for almond intake for improving lipid profile, there is a need for more well-controlled trials exclusively targeting patients with dyslipidaemia.

The effects of quinoa seed supplementation on cardiovascular risk factors: A systematic review and meta-analysis of controlled clinical trials.

This meta-analysis was designed to determine the effect of quinoa seed on cardiovascular disease (CVD) risk factors in adults. PubMed, Scopus, ISI Web of Science, and Cochrane library were searched electronically from their inception to February 2020 to identify eligible RCTs. We calculated the pooled estimates of weighted mean differences (WMDs) and their 95% confidence intervals (CIs) by using random-effects models. Five eligible RCTs representing 206 subjects were enrolled. The pooled result showed that quinoa seed supplementation significantly lowered the body weight (WMD: -1.26 kg, 95% CI: -2.35, -0.18, p = .02), waist circumference (WC) (WMD: -1.15 cm, 95% CI: -2.08, -0.21, p = .01), fat mass (FM) (WMD: -0.59%, 95% CI: -1.14, -0.03, p = .03), insulin serum level (WMD: -0.86 pmol/L, 95% CI: -13.38, -1.59, p = .01), triglyceride (TG) (WMD: -7.20 mg/dl, 95% CI: -9.52, -4.87, p < .001), total cholesterol (TC) (WMD: -6.86 mg/dl, 95% CI: -10.64, -3.08, p < .001), and low density lipoprotein (LDL) (WMD: -3.08 mg/dl, 95% CI: -5.13, -1.03, p = .003) levels. However, no significant changes were seen in other markers (p > .05). The current evidence suggests that quinoa seed might be utilized as a possible new effective and safe supplementary option to better prevent and control CVD in humans.

The effect of almond intake on anthropometric indices: a systematic review and meta-analysis.

This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize the effect of almond intake on anthropometric indices in adult subjects. We searched PubMed, Scopus, ISI Web of Science, Cochrane Library, and Google Scholar databases until January 2020 to identify relevant RCTs. Data were reported as weighted mean differences (WMDs) and standard deviations (SDs) to show the magnitude of effects of almond on body weight (BW), body mass index (BMI), waist circumference (WC), fat mass (FM), and fat-free mass (FFM). Out of 2983 reports, 28 RCTs (37 arms) were eligible for including in our meta-analysis. The pooled results, obtained using a random-effects model, showed that almond intake significantly decreased BW (WMD: -0.38 kg, 95% CI: -0.65, -0.10, p = 0.007, I2 = 30.5%) and FM (WMD: -0.58 kg, 95% CI: -0.87, -0.28, p < 0.001, I2 = 4.9%). However, we found no significant effect of almond administration on BMI (WMD: -0.30 kg m-2, 95% CI: -0.67, 0.06, p = 0.101, I2 = 62.6%), WC (WMD: -0.60 cm, 95% CI: -1.28, 0.06, p = 0.078, I2 = 0.0%), and FFM (WMD: 0.23 kg, 95% CI: -0.04, 0.50, p = 0.097, I2 = 49.5%). Overall, the current meta-analysis demonstrated that resveratrol almond intake significantly reduced weight and FM, but did not affect BMI, WC, and FFM. Further studies are still required to confirm our results.