An overview on role of nutrition on COVID-19 immunity: Accumulative review from available studies.

The novel coronavirus infection (COVID-19) conveys a serious global threat to health and economy. A common predisposing factor for development to serious progressive disease is presence of a low-grade inflammation, e.g., as seen in diabetes, metabolic syndrome, and heart failure. Micronutrient deficiencies may also contribute to the development of this state. Therefore, the aim of the present study is to explore the role of the nutrition to relieve progression of COVID-19. According PRISMA protocol, we conducted an online databases search including Scopus, PubMed, Google Scholar and web of science for published literatures in the era of COVID-19 Outbreak regarding to the status of nutrition and COVID-19 until December 2021. There were available studies (80 studies) providing direct evidence regarding the associations between the status of nutrition and COVID-19 infection. Adequate nutritional supply is essential for resistance against other viral infections and also for improvement of immune function and reduction of inflammation. Hence, it is suggested that nutritional intervention which secures an adequate status might protect against the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome - coronavirus-2) and mitigate its course. We also recommend initiation of adequate nutritional supplementation in high-risk areas and/or soon after the time of suspected infection with SARS-CoV-2. Subjects in high-risk groups should have high priority for applying this nutritive adjuvant therapy that should be started prior to administration of specific and supportive medical measures.

Magnesium supplementation beneficially affects depression in adults with depressive disorder: a systematic review and meta-analysis of randomized clinical trials.

Background: The findings from randomized clinical trials (RCTs) examining the effect of magnesium supplementation on depression are inconsistent. We decided to conduct a meta-analysis that summarizes all the evidence on the impact of magnesium supplementation on depression scores in adults with depressive disorder. Methods: We conducted a systematic search in the online databases using all related keywords up to July 2023. We included all randomized clinical trials examining the effect of magnesium, in contrast to placebo, on depression scores. Results: Finally, seven clinical trials were included in this systematic review, building up a total sample size of 325 individuals with ages ranging from 20 to 60 years on average. These RCTs resulted in eight effect sizes. Our findings from the meta-analysis showed a significant decline in depression scores due to intervention with magnesium supplements [standardized mean difference (SMD): -0.919, 95% CI: -1.443 to -0.396, p = 0.001]. Conclusion: Our review suggests that magnesium supplementation can have a beneficial effect on depression. Future high-quality RCTs with larger sample sizes must be run to interpret this effect of magnesium on depression in clinical settings. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=447909.

Higher Intake of Dietary Magnesium Is Inversely Associated With COVID-19 Severity and Symptoms in Hospitalized Patients: A Cross-Sectional Study.

Background and Aims: Magnesium is an anti-inflammatory mineral that plays a role in the innate immune system, and the relaxation of bronchial smooth muscle warrants additional attention in COVID-19. This study examined the association between magnesium intake and COVID-19 severity and related symptoms in hospitalized patients. Methods: A cross-sectional study was done enrolling 250 COVID-19 patients aged 18 to 65 years. A validated 168-item online food frequency questionnaire (FFQ) was used to assess dietary magnesium intake. COVID-19 Treatment Guidelines were used to determine COVID-19 severity, and symptoms were evaluated using a standard questionnaire. Crude and adjusted analyses were performed (Model 1: age, sex, and energy intake; Model 2: Model 1 + physical activity, supplements, corticosteroids, and antiviral drugs; Model 3: Model 2 + body mass index). Results: The mean age of participants was 44.1 ± 12.1 years, and 46% of them had severe COVID-19. Patients at the highest tertile of dietary magnesium intake had lower serum levels of inflammatory biomarkers, including CRP (11.8 ± 2.2 vs. 29.5 ± 2.1 mg/L, p < 0.001) and ESR (15.8 ± 2.4 vs. 34.7 ± 2.4 mm/hr, p < 0.001), than those at the lowest tertile. After controlling for potential confounders, we observed that a higher dietary magnesium intake was associated with a lower odds of severe COVID-19 (OR: 0.32; 95% CI: 0.15-0.70). Also, we found a significant inverse association between dietary magnesium intake and odds of COVID-19 symptoms. Conclusion: We found that higher intake of dietary magnesium was inversely associated with COVID-19 severity and symptoms.

The effect of ginger supplementation on metabolic profiles in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: There is some evidence regarding the positive effects of ginger supplementation on metabolic profile in patients with type 2 diabetes (T2DM). However, they are conflicting. The present systematic review and meta-analysis aimed to summarize earlier findings for the effect of ginger supplementation on metabolic profile in patients with T2DM. METHODS: Scopus, PubMed and Google Scholar databases were systematically searched up until September 2021 to collect all randomized clinical trials that evaluated the effect of ginger supplementation on FBS, HbA1c, TC, TG, LDL, HDL, SBP and DBP in patients with T2DM. We conducted our study according to the 2020 PRISMA guidelines. We included only English language publications. Pooled effect sizes were measured using a random-effects model and were reported as the weighted mean difference (WMD) and 95% CI. In addition, the Cochrane Collaboration's risk of bias tool was used to evaluate quality of the trials. RESULTS: In overall, 10 articles were included in this systematic review and meta-analysis. Our pooled meta-analysis indicated a significant reduction in FBS following ginger supplementation by polling 8 effect sizes [weighted mean difference (WMD): - 18.81; 95% CI: - 28.70, - 8.92), I2 = 77.4%] and in HbA1C through 7 effect sizes (WMD: -0.57; 95% CI: -0.93, -0.20, I2 =88.6%). Pooling 5 effect sizes, we found a significant reduction in SBP (WMD: -4.20; 95% CI: -7.64, -0.77, I2 =97%) and DBP [WMD: - 1.61; 95% CI: - 3.04, - 0.18), I2 = 93.2%] after supplementation with ginger. However, our pooled meta-analysis indicated that ginger supplementation had no significant influence on lipid profile involving TG, TC, LDL and HDL. CONCLUSIONS: We found significant reductions in FBS, HbA1C, SBP and DBP after supplementation with ginger in patients with T2DM compared to control group, with no significant changes in serum lipids. Further large RCTs are required to shed light on this issue.

Administration of dietary antioxidants for patients with inflammatory bowel disease: A systematic review and meta-analysis of randomized controlled clinical trials.

OBJECTIVE: Accumulating evidence has been reported regarding the effect of dietary antioxidants on clinical variables in IBD patients, however, findings are controversial. This systematic review and meta-analysis aimed to investigate effect of dietary antioxidants on clinical variables in patients with IBD or its subtypes. METHODS: We searched PubMed, Scopus, and ISI Web of Science from inception to January 2021 using relevant keywords. Data were pooled by using the random-effect model. All statistical analyses were done using STATA version 14. RESULTS: Our meta-analysis was exclusively done on studies about the effect of curcumin on IBD patients, because limited studies were done on other antioxidants. Curcumin administration resulted in significant increment of clinical remission in patients with IBD (SMD: 0.86%, 95% CI: 0.16, 1.56, p = 0.016), significant remission in clinical symptoms (SMD: -0.96 score, 95% CI: -1.34, -0.57, p < 0.001), and significant increment in endoscopic remission in IBD patients (SMD: 0.51%, 95% CI: 0.16, 0.85, p = 0.004), comparing to control group. Curcumin supplementation also made better clinical response than control group (SMD: 0.74%, 95% CI: 0.22, 1.26, p = 0.005) and also resulted in significant improvement in quality of life of patients with IBD, as compared to control group (SMD: 1.23 score, 95% CI: 0.72, 1.74, p < 0.001). CONCLUSIONS: Our meta-analysis showed that curcumin significantly improved clinical and endoscopic remissions in IBD patients. This supplementation also caused significant reduction in clinical symptoms of IBD patients along with better clinical response and the increased quality of life. Further researches with larger sample size and longer period of intervention are required to evaluate efficacy of dietary antioxidants on clinical variables in patients with IBD.

Effects of curcumin supplementation on inflammatory biomarkers in patients with Rheumatoid Arthritis and Ulcerative colitis: A systematic review and meta-analysis.

BACKGROUND: Although previous studies have examined the impact of curcumin supplementation on cytokine levels in patients with autoimmune disorders, we were unable to find a systematic review of the effect of curcumin supplementation on inflammatory biomarkers such as CRP and ESR in patients with rheumatoid arthritis or ulcerative colitis; therefore we conducted this systematic review and meta-analysis. METHODS: Relevant studies published from inception to December 2020 were systematically searched through the PubMed, SCOPUS, and google scholar databases. We conducted our systematic review and meta-analysis according to the 2020 PRISMA guidelines. The quality of the papers were assessed by using the Cochrane Collaboration's risk of bias tool. Included studies were randomized clinical trials on the effects of supplementation with curcumin or its derivative on inflammatory factors in patients with rheumatoid arthritis and ulcerative colitis. Pooled effect sizes were calculated using a random-effects model and reported as the weighted mean difference (WMD) and 95 % CI. RESULTS: In all, six studies met the inclusion criteria for this study. Curcumin supplementation in doses of 250-1500 mg/day over 8-12 weeks was observed to be associated with decreases in CRP and ESR in adult patients with rheumatoid arthritis and ulcerative colitis in comparison with the control group (WMD: -0.42; 95 % CI: -0.59, -0.26, I2 = 94.3 %; WMD: -55.96; 95 % CI: -93.74, -18.17, I2 = 99.7 %, respectively). Significant findings were also observed based on subgroup analyses by the study sample size, duration, participants' age, curcumin dosage, and type of disease. CONCLUSIONS: Curcumin supplementation was associated with significant reductions in levels of CRP and ESR in patients with rheumatoid arthritis and ulcerative colitis. Earlier studies reported curcumin as a safe complementary therapy for several diseases. However, a handful of studies were found on the effect of curcumin on autoimmune diseases despite our comprehensive search. Further studies are therefore warranted in this area.

The effect of L-arginine supplementation on obesity-related indices: A systematic review and meta-analysis of randomized clinical trials.

The clinical studies regarding the effect of L-arginine in human anthropometry have not been fully consistent, therefore, we carried out a systematic review and meta-analysis of randomized clinical trials in order to precisely evaluate and quantify the efficacy of L-arginine on weight, waist circumference, and BMI. We searched online databases including PubMed, SCOPUS, and Google Scholar for relevant articles up to September 2017. Eligible articles were reviewed by two independent investigators. Mean differences of the outcomes were used for calculation of weighted mean difference (WMD) derived from the random-effects model. Statistical heterogeneity between studies was examined using Cochran's Q-test and I2 index. Funnel plot and Egger's tests were performed to assess the publication bias. In our initial search, we found 1598 publications, of which 8 RCTs (9 treatment arms) were included. The results of the meta-analysis displayed a significant reduction in WC following L-arginine supplementation (WMD: -2.97 cm; 95% CI: -4.75 to -1.18, P = 0.001). However, L-arginine intervention had not elicited a significant effect on BMI (WMD: -0.51 kg/m2; 95% CI: -1.11 to .08, P = 0.09) and body weight (WMD: -0.57 kg; 95% CI: -1.77 to 0.61, P = 0.34). Subgroup analyses displayed that longer-term interventions (≥8 weeks) had a positive effect on body weight and using < 8 g/day L-arginine with longer duration (≥8 weeks) could significantly decrease BMI. In conclusion, this meta-analysis result suggested L-arginine supplementation could reduce waist circumference without any significant effect on body weight and body mass index.

Effects of flaxseed oil supplementation on biomarkers of inflammation and oxidative stress in patients with metabolic syndrome and related disorders: A systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to analyze the effects of flaxseed oil supplementation on biomarkers of inflammation and oxidative stress in patients with metabolic syndrome (MetS) and related disorders. METHODS: Databases including PubMed, Scopus, EMBASE, Web of Science, and Cochrane Central library were searched until January 31th, 2019. RESULTS: 14 effect sizes from 12 studies were identified eligible to be included in current meta-analysis. Flaxseed supplementation resulted in a significant reduction in interleukin 6 (IL-6) (WMD: -0.22; 95% CI: -0.43, -0.01) and malondialdehyde (MDA) (WMD: -0.17; 95% CI: -0.31, -0.03) and a significant increase in total antioxidant capacity (TAC) levels (WMD: 137.25; 95% CI: 68.04, 206.47). Flaxseed oil supplementation did not affect other biomarkers of inflammation and oxidative stress. CONCLUSIONS: Overall, this meta-analysis demonstrated flaxseed oil supplementation decreased IL-6 and MDA levels, and increased TAC, but did not affect other biomarkers of inflammation and oxidative stress among patients with MetS and related disorders. This suggests that flaxseed oil supplementation may have played an indirect role in improved clinical symptoms in diseases with metabolic disorders.

Is there any association between fruit consumption and the risk of gestational diabetes mellitus? A systematic review and meta-analysis.

AIM: Although a considerable number of studies have illustrated the positive effects of fresh fruits on metabolic status, the impacts of fruits on the risk of gestational diabetes mellitus (GDM) are inconsistent. In consideration of this issue, we aimed to systematically summarize the findings of cohort studies with respect to the link between fresh fruits and the risk of GDM. METHOD: We selected cohort studies with English language indexed in PubMed/Medline, Scopus, Web of Science, and Embase from 2000 to 31 January 2018. To examine the link between fresh fruits and the risk of GDM development, relative risk (RR) and 95 % confidence intervals (CIs) for the highest versus the lowest consumption of fruits were pooled using a random effect model and the DerSimonian and Laird method. RESULTS: Out of 2522 publications, finally 5 cohort studies were obtained. No significant association between fruit consumption and GDM incidence was found (Pooled RR: 0.95; 95 % CI: 0.84, 1.08; I2: 90.3 %, p = 0001). In women who consumed higher amount of fruits before pregnancy, the risk of GDM was 5% lower than in those who consumed lower amount of fruits (0.95; 95 %CI: 0.91, 0.99, I2: 0%, p = 0.85). No link was obtained between fruit consumption during the pregnancy and GDM onset (1.18, 95 % CI: 0.48, 2.91; I2:94.6 %, p = 0.0001). CONCLUSION: In women who consumed greater fruits before pregnancy, the risk for GDM was 5 % lower than those consumed lower amounts of fruits, while there was no link between fruit consumption throughout the pregnancy and GDM onset. However, due to limited studies and considerable heterogeneity, the findings must be interpreted with great caution.

A systematic review and meta-analysis: The effects of probiotic supplementation on metabolic profile in patients with neurological disorders.

BACKGROUND AND OBJECTIVE: The objective of meta-analysis of randomized controlled trials (RCTs) was to evaluate the effects of probiotic supplementation on metabolic status in patients with neurological disorders. METHODS: The following databases were search up to April 2019: Pubmed, Scopus, Google scholar, Web of Science, and Cochrane Central Register of Controlled Trials. The quality of the relevant extracted data was assessed according to the Cochrane risk of bias tool. Data were pooled by the use of the inverse variance method and expressed as mean difference with 95 % Confidence Intervals (95 % CI). RESULTS: Nine studies were included in this meta-analysis. The findings suggested that probiotic supplementation resulted in a significant reduction in C-reactive protein (CRP) [Weighted Mean Difference (WMD): -1.06; 95 % CI: -1.80, -0.32] and malondialdehyde (MDA) levels (WMD: -0.32; 95 % CI: -0.46, -0.18). Supplementation with probiotics also significantly reduced insulin (WMD: -3.02; 95 % CI: -3.88, -2.15) and homeostatic model assessment for insulin resistance (HOMA-IR) (WMD: -0.71; 95 % CI: -0.89, -0.52). Probiotics significantly reduced triglycerides (WMD: -18.38; 95 % CI: -25.50, -11.26) and VLDL-cholesterol (WMD: -3.16; 95 % CI: -4.53, -1.79), while they increased HDL-cholesterol levels (WMD: 1.52; 95 % CI: 0.29, 2.75). CONCLUSION: This meta-analysis demonstrated that taking probiotic by patients with neurological disorders had beneficial effects on CRP, MDA, insulin, HOMA-IR, triglycerides, VLDL-cholesterol and HDL-cholesterol levels, but did not affect other metabolic parameters.

Effects of whey protein on glycemic control and serum lipoproteins in patients with metabolic syndrome and related conditions: a systematic review and meta-analysis of randomized controlled clinical trials.

BACKGROUND: This systematic review and meta-analysis aimed to assess the effects of whey protein on serum lipoproteins and glycemic status in patients with metabolic syndrome (MetS) and related disorders. METHODS: Online databases, such as Web of Science, Cochrane Library, PubMed and Scopus were systematically searched by two independent authors from inception until 30th April 2020 for English randomized clinical trials investigating the efficacy of whey protein administration in subjects with Mets or related conditions on the parameters of glycemic and lipid control compared to certain control. In order to evaluate the included studies' methodological quality, Cochrane Collaboration risk of bias tool was applied. Using Cochrane's Q test and I-square (I2) statistic, the included trials' heterogeneity was also examined. Using a random-effects model, data were pooled, and weighted mean difference (WMD) was considered as the overall effect size. RESULTS: Twenty-two studies were selected to be included in this meta-analysis. Consumption of whey protein resulted in significant reduction of HbA1c (WMD: -0.15; 95% CI: - 0.29, - 0.01) insulin (WMD: -0.94; 95% CI: - 1.68, - 0.21) and homeostasis model assessment-estimated insulin resistance (HOMA-IR) (WMD: -0.20; 95% CI: - 0.36, - 0.05). A significant reduction in triglycerides levels (WMD: -17.12; 95% CI: - 26.52, - 7.72), total cholesterol (WMD: -10.88; 95% CI -18.60, - 3.17), LDL-cholesterol levels (WMD: -8.47 95% CI: - 16.59, - 0.36) and total cholesterol/HDL-cholesterol ratio (WMD: -0.26; 95% CI: - 0.41, - 0.10) was found as well. CONCLUSIONS: This meta-analysis suggests that supplementation with whey protein had beneficial effect on several indicators of glycemic control and lipid parameters in patients with MetS and related conditions.

Clinical effectiveness of zinc supplementation on the biomarkers of oxidative stress: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Oxidative stress plays an important role in the occurrence of chronic diseases. Zinc supplementation is also known to be an antioxidant agent. While, there is no review on the effects of zinc supplementation on oxidative stress, this study aimed to systematically summarize randomized clinical trials (RCTs) which have evaluated the impacts of zinc supplementation on oxidative stress biomarkers. METHODS: Systematic searches were performed using the PubMed/Medline, Scopus, and Google Scholar databases, up to April 2020. All RCTs assessed the effect of oral zinc supplementation on serum malondialdehyde (MDA), total antioxidant capacity (TAC), glutathione (GSH), and nitric oxide (NO) levels, were included. For each variable, mean differences (MD) and standard deviations (SDs) were combined using the random-effects model, and the fractional polynomial model was used to implement the dose-response analysis. RESULTS: Ten RCTs were included. The pooled analysis of data showed that zinc supplementation significantly reduced MDA levels (MD: -0.42 µmol/L; 95 % CI: -0.71 to -0.13), increased serum TAC (MD: 225.96 mmol/L; 95 % CI: 68.42-383.5) and GSH levels (MD: 49.99 µmol/L; 95 % CI: 2.25 t 97.73), compared with the placebo group. In contrast, no significant changes were seen in NO levels following zinc supplementation (MD: -1.66 µmol/L; 95 % CI: -5.89 to 2.57). Dose-response analysis showed a significant non-linear relationship between zinc supplementation dosage and serum levels of MDA (p < 0.01), but not other biomarkers. CONCLUSIONS: The current study showed that zinc supplementation would significantly decrease MDA and increase TAC and GSH, but not NO levels. Thus, it encourages the use of zinc supplementation in oxidative stress-related diseases.

Effects of soy milk consumption on gut microbiota, inflammatory markers, and disease severity in patients with ulcerative colitis: a study protocol for a randomized clinical trial.

BACKGROUND: Several strategies are recommended to alleviate clinical symptoms of ulcerative colitis (UC). Soy milk may affect UC through its anti-inflammatory properties. However, no study has examined the effects of soy milk consumption on gut microbiota and inflammatory biomarkers in patients with UC. The current study will be done to examine the effects of soy milk consumption on UC symptoms, inflammation, and gut microbiota in patients with UC. METHODS: This study is a randomized clinical trial, in which thirty patients with mild to moderate severity of UC will be randomly allocated to receive either 250 mL/day soy milk plus routine treatments (n = 15) or only routine treatments (n = 15) for 4 weeks. Assessment of anthropometric measures and biochemical indicators including serum concentrations of high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interferon gamma (IFN-γ) will be done at the study baseline and end of trial. In addition, the quantity of butyrate-producing bacteria including Clostridium cluster IV, Faecalibacterium prausnitzii, and Roseburia spp.; prebiotic bacteria including Lactobacillus spp. and Bifidobacteria spp.; and mucus-degrading bacteria including Akkermansia muciniphila, Bacteroides fragilis, and Ruminococcus spp., as well as calprotectin and lactoferrin levels, will be explored in fecal samples. Also, the Firmicutes to Bacteroidetes ratio which is of significant relevance in human gut microbiota composition will be assessed. DISCUSSION: Altered gut microbiota has been reported as an important contributing factor to inflammation in patients with inflammatory bowel disease (IBD). Soy milk contains several components such as phytoestrogens with potential anti-inflammatory properties. This product might affect gut microbiota through its protein and fiber content. Therefore, soy milk might beneficially affect systemic inflammation, gut microbiota, and then clinical symptoms in patients with UC. TRIAL REGISTRATION: Iranian Registry of Clinical Trials (www.irct.ir) IRCT20181205041859N1. Registered on 27 January 2019.

Effects of Nigella sativa on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress: A systematic review and meta-analysis of randomized controlled clinical trials.

The aim of this systematic review and meta-analysis was to evaluate the effects of Nigella sativa (N. sativa) on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress. Two independent authors systematically examined online databases consisting of, EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until October 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of the studied trials. The heterogeneity among the included studies were assessed using the Cochrane's Q test and I-square (I2 ) statistic. Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. A total of 50 trials were included in this meta-analysis. We found a significant reduction in total cholesterol (WMD: -16.80; 95% CI: -21.04, -12.55), triglycerides (WMD: -15.73; 95% CI: -20.77, -10.69), LDL-cholesterol (WMD: -18.45; 95% CI: -22.44, -14.94) and VLDL-cholesterol (WMD: -3.72; 95% CI: -7.27, -0.18) following supplementation with N. sativa. In addition, there was significant reductive effect observed with N. sativa on fasting glucose (WMD: -15.18; 95% CI: -19.82, -10.55) and HbA1C levels (WMD: -0.45; 95% CI: -0.66, -0.23). Effects of N. sativa on CRP (WMD: -3.61; 95% CI: -9.23, 2.01), TNF-α (WMD: -1.18; 95% CI: -3.23, 0.86), TAC (WMD: 0.31; 95% CI: 0.00, 0.63), and MDA levels (WMD: -0.95; 95% CI: -2.18, 0.27) were insignificant. This meta-analysis demonstrated the beneficial effects of N. sativa on fasting glucose, HbA1c, triglycerides, total-, VLDL-, LDL-cholesterol levels.

Correction to: The effect of zinc supplementation on blood pressure: a systematic review and dose-response meta-analysis of randomized-controlled trials.

The original version of this article unfortunately contained a mistake. The family name of "Israel Júnior Borges do Nascimento" was incorrect.

The effects of probiotic supplementation on mental health, biomarkers of inflammation and oxidative stress in patients with psychiatric disorders: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND OBJECTIVE: In the current meta-analysis of randomized controlled trials (RCTs), the effects of probiotic supplementation on mental health, biomarkers of inflammation and oxidative stress in patients with psychiatric disorders were assessed. METHODS: The following databases were search up to February 2019: PubMed, Scopus, Web of Science, Google scholar and Cochrane Central Register of Controlled Trials. RESULTS: Twelve studies were included in the current meta-analysis. The findings demonstrated that probiotic supplementation resulted in a significant reduction in Hamilton Depression Rating Scale (HAMD) [Weighted Mean Difference (WMD): -9.60; 95 % CI: -10.08, -9.11]. In addition, a significant reduction in C-reactive protein (CRP) (WMD: -1.59; 95 % CI: -2.22, -0.97), interleukin 10 (IL-10) (WMD: -0.29; 95 % CI: -0.48, -0.11) and malondialdehyde (MDA) levels (WMD: -0.38; 95 % CI: -0.63, -0.13) was found after probiotics supplementation. No significant change was seen in Beck Depression Inventory (BDI) score (WMD: -11.17; 95 % CI: -24.99, 2.65), tumor necrosis factor-α (TNF-α) (WMD: -0.12; 95 % CI: -0.20, -0.05), IL-1B (WMD: -0.34; 95 % CI: -1.43, 0.74), IL-6 (WMD: 0.03; 95 % CI: -0.32, 0.38), nitric oxide (NO) (WMD: -0.54; 95 % CI: -2.16, 1.08), glutathione (GSH) (WMD: 46.79; 95 % CI: -17.25, 110.83) and total antioxidant capacity (TAC) levels (WMD: 15.21; 95 % CI: -59.96, 90.37) after probiotics supplementation. CONCLUSION: Overall, the current meta-analysis demonstrated that taking probiotic by patients with psychiatric disorders had beneficial effects on HAMD, CRP, IL-10 and MDA levels, but it did not affect BDI score, other markers of inflammation and oxidative stress.

The effect of zinc supplementation on blood pressure: a systematic review and dose-response meta-analysis of randomized-controlled trials.

PURPOSE: Despite previous investigations on the effects of zinc supplementation on blood pressure, inconsistent findings are available in this regard. Therefore, we conducted a systematic review and meta-analysis of randomized clinical trials on the effects of zinc supplementation on blood pressure (BP) in adults. METHODS: Relevant studies published up to September 2019 were searched through PubMed/Medline, Scopus, ISI Web of Science, and Google Scholar using suitable keywords. All randomized clinical trials (RCTs) that examined the effect of oral zinc supplementation on systolic blood pressure (SBP) or diastolic blood pressure (DBP) in adults were included. RESULTS: Overall, nine trials were included in our study. Zinc supplementation significantly reduced SBP compared to the control [weighted mean differences (WMD) - 1.49 mmHg; 95% CI - 2.85 to - 0.13; P = 0.03]. However, zinc supplementation had no significant effects on DBP (WMD - 0.88 mmHg; 95% CI - 2.04 to 0.29; P = 0.14). Nonlinear analysis failed to indicate a significant influence of supplementation dosage or duration on both SBP and DBP. Sensitivity analysis showed that no individual study had a significant impact on our final results. In addition, we found no evidence for the presence of small-study effects among studies for both SBP and DBP. CONCLUSION: We found a significant reduction in SBP following zinc supplementation. However, zinc supplementation had no significant effect on DBP. In addition, no nonlinear association was found between supplementation dosage and duration with changes in both SBP and DBP. Further RCTs using different dosages of zinc in various durations are required to confirm our conclusion.

The effects of omega-3 fatty acids supplementation on metabolic status in pregnant women: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND OBJECTIVE: Data regarding the effects of omega-3 polyunsaturated fatty acids (PUFA) supplementation on metabolic status of pregnant women are limited. This systematic review and meta-analysis were done based on randomized controlled trials (RCTs) dealing with the effects of omega-3 PUFA supplementation on glycemic control, lipoproteins, inflammation and oxidative stress in pregnant women. METHODS: Following databases were searched for eligible studies published from inception to until 2019: MEDLINE, EMBASE, Web of Science, PubMed, Scopus, Cochrane Library, and Google scholar. Studies that evaluated the effect of omega-3 PUFA supplementation on parameters of glycemic control, lipoproteins, inflammation and oxidative stress in pregnant women were found by using the key MeSH. A study quality assessment was performed using the Cochrane Collaboration risk of bias tool and heterogeneity between studies was statistically computed using Cochrane's Q test and I-square (I2). Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. RESULTS: No significant effects of omega-3 PUFA supplementation on FPG, insulin, insulin resistance, total cholesterol, triglycerides, LDL-cholesterol, total cholesterol/HDL-cholesterol, interleukin 6 (IL-6), IL-8, and malondialdehyde were found. However, omega-3 PUFA significantly increased serum concentrations of HDL-cholesterol (WMD: 3.10; 95% CI: 0.18, 6.03) and reduced C-reactive protein (WMD: -1.85; 95% CI: -2.61, -1.09). CONCLUSION: Based on the results of this meta-analysis omega-3 PUFA supplementation during pregnancy has a significant beneficial effect on HDL-cholesterol, and C-reactive protein.

The effects of L-carnitine supplementation on indicators of inflammation and oxidative stress: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE: Several trials investigated the efficacy of L-carnitine administration on markers of inflammation and indicators of oxidative stress; however, their findings are controversial. The aim of this study was to conduct a comprehensive meta-analysis and a critical review, which would analyze all randomized controlled trials (RCTs) in order to determine the effects of L-carnitine supplementation on inflammatory markers and oxidative stress. METHODS: An electronic search was performed using Scopus, Cochrane Library, PubMed, Google scholar and Web of Science databases on publications from 1990 up to May 2020. Human RCTs conducted in healthy subjects or participants with certain disorders which investigating the efficacy of L-carnitine supplementation compared to control (placebo, usual treatment or no intervention) on inflammation and oxidative markers were included. Data were pooled applying a random-effects model and as the overall effect size, weighted mean difference (WMD) was presented. Between heterogeneity among studies was computed using Cochran's Q test and I-square (I2). Quality of studies assessed using the Jadad scale. Dose-response analysis was measured using meta-regression. The funnel plot, as well as the Egger's regression test was applied to determine the publication bias. RESULTS: 44 trials (reported 49 effect sizes for different outcomes of interest) met the inclusion criteria for this meta-analysis. According to the findings, L-carnitine supplementation resulted in a significant reduction in C-reactive protein (CRP) (WMD: -0.10; 95% CI: -0.14, -0.06), interleukin 6 (IL-6) (WMD: -1.87; 95% CI: -2.80, -0.95), tumor necrosis factor-α (TNF-α) levels (WMD: -1.43; 95% CI: -2.03, -0.84), and malondialdehyde (MDA) (WMD: -0.47; 95% CI: -0.76, -0.18) levels, while there was a significant increase in superoxide dismutase (SOD) (WMD: 2.14; 95% CI: 1.02, 3.25). However, no significant effects of L-carnitine on glutathione peroxidase (GPx) (WMD: 0.02; 95% CI: -0.01, 0.05) and total antioxidant capacity (TAC) (WMD: 0.14; 95% CI: -0.05, 0.33) were found. CONCLUSIONS: L-carnitine supplementation was associated with lowering of CRP, IL-6, TNF-α, and MDA, and increasing SOD levels, but did not affect other inflammatory and oxidative stress biomarkers.

Potato consumption and risk of all cause, cancer and cardiovascular mortality: a systematic review and dose-response meta-analysis of prospective cohort studies.

A systematic review and meta-analysis of prospective cohort studies was conducted to examine the association of potato consumption and risk of all-cause, cancer and cardiovascular mortality in adults. We searched PubMed, Scopus databases up to September 2018 for all relevant published papers. All analyses were performed on HRs or RRs and 95% CIs. In twenty prospective studies, 25,208 cases were reported for all-cause mortality, 4877 for cancer mortality and 2366 for CVD mortality. No significant association was found between potato consumption and risk of all-cause (0.90; 95% CI: 0.8, 1.02, p = 0.096) and cancer (1.09; 95% CI: 0.96, 1.24, P = 0.204) mortality. In addition, no significant linear association was found between each 100 g/d increments in potato consumption and risk of all-cause (P = 0.7) and cancer (P = 0.09) mortality. Moreover, nonlinear association between potato consumption and risk of cancer mortality was non-significant (P-nonlinearity = 0.99). In addition, two of three studies which examined the association of potato consumption with CVD mortality did not find any significant relationship. There was no evidence for publication bias in this study. We failed to find significant association between potato consumption and risk of mortality. Further studies are required to confirm this issue.