Dietary intake, biomarkers and supplementation of fatty acids and risk of coronary events: a systematic review and dose-response meta-analysis of randomized controlled trials and prospective observational studies.

We aimed to review the association of dietary fats and risk of coronary events in adults. We searched PubMed, Embase, CENTRAL, Scopus, and Web of Sciences to April 2022 for prospective cohorts and randomized trials investigating the association of dietary intake and biomarkers of fats and fatty acid interventions and the risk of coronary events. We performed random-effects meta-analyses to estimate relative risk (RR) for the top versus bottom tertiles of exposures. One-hundered sixty-five prospective cohorts and randomized trials were included. Dietary intake and biomarkers of total fat and saturated, monounsaturated, and polyunsaturated fatty acids were not associated with the risk of coronary events. Dietary intake of trans fatty acids, palmitic acid, stearic acid, and saturated fatty acids from meat and unprocessed meat was modestly associated with a higher risk and, in contrast, intake of alpha-linolenic acid, long-chain omega-3 fatty acids, and linoleic acid was modestly associated with a lower risk. Supplementation with long-chain omega-3 fatty acids and increasing the consumption of alpha-linolenic and linoleic acids in place of saturated fats reduced the risk of coronary events. Existing evidence, in its totality, provides a modest support in favor of current recommendations suggesting replacement of saturated fats with polyunsaturated fats.

Effects of probiotic/synbiotic supplementation on body weight in patients with diabetes: a systematic review and meta-analyses of randomized-controlled trials.

OBJECTIVE: The aim of the present study was to assess the effect of probiotic/synbiotic supplementation on anthropometric measures in adults with diabetes, independent of body weight. METHODS: PubMed, Scopus, Web of Sciences and the Cochrane Library were searched for randomized controlled trials (RCTs) up until December 14, 2022. The effect sizes were pooled using an inverse-variance random-effects model. The methodological quality of studies as well as the quality of evidence was assessed using standard tools. RESULTS: Thirty-two RCTs met the established inclusion criteria. Overall, compared with the respective control groups, probiotic/synbiotic supplementation resulted in a significant reduction in body weight (weighted mean difference [WMD]: -0.50 kg; 95% CI: -0.83, -0.17; I2 = 79.8%, n = 27 studies]), body mass index (WMD: -0.24 kg/m2; 95% CI: -0.39, -0.09; I2 = 85.7%, n = 30 studies), and waist circumference (WMD: -0.90 cm; 95% CI: -1.13, -0.52; I2 = 0%, n = 11 studies). However, hip circumference and waist to hip ratio were not significantly improved. CONCLUSIONS: Our analysis revealed that probiotic/synbiotic supplementation may assist with weight management in patients with diabetes, especially when consumed at higher doses, in younger adults, and in participants with obesity. However, more studies are needed to elucidate the anti-obesity effects of specific strains of probiotics/synbiotics.

Resveratrol may mildly improve renal function in the general adult population: A systematic review and meta-analysis of randomized controlled clinical trials.

Whether renal health biomarkers can benefit from resveratrol supplements is unknown. Thus, we conducted a systematic review and meta-analysis to summarize evidence from randomized controlled trials investigating the effect of resveratrol supplementation on renal health biomarkers. We hypothesized that resveratrol supplementation is associated with improved renal health biomarkers. Four electronic databases, including PubMed, Scopus, and Institute for Scientific Information Web of Science, and Cochrane Central, were searched for relevant articles up to February 2023. The pooled effect sizes were estimated using a random effects model and expressed as weighted mean difference (WMD) and 95% CI. In total, 32 articles were eligible for inclusion in the current meta-analysis. The pooled results indicated that resveratrol significantly decreased blood urea nitrogen (weighted mean difference [WMD]= -0.84 mg/dL; 95% CI, -1.48 to -0.20; P = .01; I2 = 64.4%) and creatinine levels (WMD = -1.90 µmol/L; 95% CI, -3.59 to -0.21; P = .03; I2= 52.1%), and increased glomerular filtration rate (WMD = 7.58 mL/min/1.73 m2; 95% CI, 5.25-9.91; P < .001; I2 = 0%). The favorable change of blood urea nitrogen was significant in studies with short follow-up duration (12 weeks or less), with lower doses of resveratrol (less than 500 mg/d), and those conducted in patients with diabetes. However, higher doses of resveratrol are needed to observe significant reductions in creatinine. No significant change was observed in albumin, total protein, and uric acid concentrations. This meta-analysis provides a low certainty of evidence indicating a mild renal protective effect of resveratrol in adults. Further high-quality evidence in patients with impaired renal function and estimates of mortality risk in these patients is required before resveratrol can be advocated as an adjuvant therapy.

Oral vitamin D supplementation and body weight in children and adolescents: a systematic review and meta-analysis of randomized controlled trials.

This study was designed to ascertain whether oral vitamin D supplementation (oral supplementation and fortified foods) is associated with changes in body weight measures in children and adolescents, using a systematic review and meta-analysis of randomized controlled trials (RCTs). PubMed, Scopus, Cochrane, and Web of Science databases were searched from inception to October 28, 2022. The mean difference and corresponding 95% confidence interval (CI) of interested outcomes were pooled using a random-effects model. Twenty-one RCTs were included in the meta-analysis, and the results showed a significant decrease in body mass index (BMI) following vitamin D supplementation in children and adolescents (n = 9 studies, 1029 participants; weighted mean difference: - 0.43 kg/m2, 95% CI: - 0.79, - 0.08; P = 0.02; I2 = 58.5%). Overall, oral vitamin D supplementation had no significant effect on body weight and other anthropometric indices, including fat mass, lean mass, waist circumference, BMI Z-score, and height. Although results of body weight changed to significant after sensitivity analysis (WMD = 0.39 kg, 95% CI = 0.01, 0.78; P = 0.04; I2 = 0%, P-heterogeneity = 0.71), we also found significant weight gain in healthy pediatric population, and when the dose of vitamin D supplementation was up to 600 IU/day, the certainty of evidence was very low for weight, moderate for height and BMI, and low for the remaining outcomes. CONCLUSION: Our results suggest that vitamin D supplementation may lead to a statistically significant weight gain in children and adolescents, while BMI was reduced. Although no significant change was observed in height, it seems vitamin D supplementation may elicit these changes by increasing skeletal growth; however, this remains to be verified. Further high-quality RCTs, with longer duration and larger sample sizes, are needed to yield more certain evidence in this regard. WHAT IS KNOWN: • Available evidence indicates an inverse association between body weight/fat mass and vitamin D status in children and adolescents; however, findings regarding the effect of vitamin D supplementation on anthropometric measurements in children are controversial. WHAT IS NEW: • Our results showed a significant decrease in BMI following vitamin D supplementation in children. • A significant weight gain also was observed after sensitivity analysis, and in healthy pediatric population, and when the dose of vitamin D supplementation was up to 600 IU/day.

The effect of resveratrol supplementation on biomarkers of liver health: A systematic review and meta-analysis of randomized controlled trials.

This study aimed to evaluate the effect of resveratrol on liver biomarkers in adult participants, using systematic review and meta-analysis of randomized controlled trials. PubMed, Scopus, Web of Science and Cochran Library was searched, up to October 2021. The pooled effects were calculated using a random-effects model and expressed as weighted mean difference and 95% confidence interval. The methodological quality of studies as well as certainty of evidence were assessed by standard tools. Thirty-seven relevant trials were found. Although overall analysis found no significant change, subgroup analysis showed a significant improvement in alanine aminotransferase (ALT; -7.79 U/L) and glutamyl transferase (-6.0 U/L) in patients with liver disorders, and ALT (-2.22 U/L) in younger adults; however, high-dose supplementation (>1,000 mg/day) appeared to increase alkaline phosphatase concentration (+5.07 U/L). ALT also increased in older adults (+2.33 U/L) following resveratrol supplementation. We found resveratrol did not have a significant effect on liver health in the general population. However, resveratrol could be effective in patients with liver disorders. Our findings also suggest that high-dose resveratrol administration and supplementation in older adults should be performed with caution. Further high-quality clinical trials are also needed to firmly establish the clinical efficacy of resveratrol.

Probiotics supplementation and brain-derived neurotrophic factor (BDNF): a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND AIMS: An emerging body of evidence has demonstrated the beneficial effects of probiotics on various mental health conditions. In this systematic review and meta-analysis, we sought to examine the effects of probiotics supplementation on brain-derived neurotrophic factor (BDNF) in adults. METHODS: PubMed, Scopus, ISI Web of Science, and the Cochrane Library were searched, from database inception to April 2021, for eligible randomized controlled trials (RCTs). We pooled mean differences and standard deviations from RCTs using random-effect models. RESULTS: Overall, meta-analysis of 11 trials (n = 648 participants) showed no significant changes in serum level of BDNF following probiotics. However, subgroup analysis revealed that probiotics increased BDNF levels in individuals suffering from neurological disorders (n = 214 participants; WMD = 3.08 ng/mL, 95% CI: 1.83, 4.34; P = 0.001; I2 = 7.5%; P-heterogeneity 0.34), or depression (n = 268 participants; WMD = 0.77 ng/mL, 95% CI: 0.07, 1.47; P = 0.032; I2 = 88.4%; P-heterogeneity < 0.001). Furthermore, a significant increase in BDNF levels was found in studies that administered the mixture of Lactobacillus and Bifidobacterium genera, and were conducted in Asia . CONCLUSION: Our main findings suggest that probiotics may be effective in elevating BDNF levels in patients with depression and neurological disorders, and a mixed of Lactobacillus and Bifidobacterium appear to show greater efficacy than the single genus supplement. The low quality of evidence reduces clinical advocacy, and indicates that more large-scale, high-quality, RCTs are needed to facilitate reliable conclusions.

Comparison of nutritional supplements for glycemic control in type 2 diabetes: A systematic review and network meta-analysis of randomized trials.

AIMS: Direct and indirect evidence were combined in this systematic-review and network meta-analysis (NMA) to assess and compare the effect of nutritional supplements on glycemic control, and rank the supplements accordingly. METHODS: PubMed, Scopus, and Web of Science were searched up to April 2021. We included randomized controlled trials that investigated the effect of vitamins D, C, and E, magnesium, zinc, calcium, selenium, and omega-3 on at least one glycemic marker, including glycated hemoglobin (HbA1c), fasting blood sugar (FBS), homeostasis model assessment-estimated insulin resistance (HOMA-IR), HOMA-B, and insulin, in adults with type 2 diabetes. To estimate effectiveness of supplements, a random-effects NMA in the Bayesian framework was applied. To assess risk of bias, Cochrane Collaboration Tool was used. RESULTS: Analysis of 178 studies indicated that zinc, vitamin D, omega-3, vitamin C, and vitamin E were effective in reducing HbA1c with low certainty. For reduction of FBS, zinc, vitamin D, and vitamin C, and for HOMA-IR, vitamin D were effective with low certainty. None of the supplements were effective in the reduction of insulin and HOMA-B with low certainty. After excluding poor-quality studies, only vitamin D was significantly effective in reducing all of the markers. Consistently, when the analysis was restricted to studies with a duration of ≥12-weeks, vitamin D reduced HbA1c, FBS, and HOMA-IR. CONCLUSIONS: Vitamin D supplementation was more effective compared to other supplements in improving HbA1c, FBS, and HOMA-IR, albeit with low certainty of evidence. This result was confirmed by low-risk of bias studies. REGISTRATION: CRD42021240691.

The effects of lycopene supplementation on insulin-like growth factor-1 and insulin-like growth factor binding proteins: A systematic review of randomized controlled trials.

Lycopene has been posited to regulate insulin-like growth factor-1 (IGF-1). We aimed to conduct a systematic review of the effects of lycopene on circulating IGF-1 and insulin-like growth factor binding proteins (IGFBPs) in adults. A systematic search was carried out in PubMed, Scopus, ISI Web of Science, and the Cochrane Library databases for randomized controlled trials (RCTs), published from inception until March 2020. A total of 11 studies fulfilled the selection criteria. Eleven studies examined the effect of lycopene supplementation on IGF-1, one of which reported a significant reduction. Moreover, three, four, and ten studies were found for IGFBP-1, IGFBP-2, and IGFBP-3, respectively; where one study found a significant increase in these proteins. In conclusion, no consistent modifying effect of lycopene supplementation on IGF-1 and IGFBPs levels are evident in the literature. More research is needed to explore the effect of lycopene on IGF-1 system.

The effect of lycopene supplement from different sources on prostate specific antigen (PSA): A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Prostate cancer is a major malignancy, affecting men, worldwide. The protective effect of dietary or supplemental lycopene on prostate cancer has been reported in several studies; however, the findings are equivocal. OBJECTIVE: The aim of this study was to evaluate the effects of supplemental lycopene on PSA level, by conducting a systematic review and meta-analysis of randomized controlled trials. METHODS: We searched online databases, including PubMed, Scopus, and Web of Science, up to 9 Jun 2020, to obtain relevant publications. The publication search was not limited by language or date. RESULTS: A total of 1036 records were identified in the systematic search; from these, 9 were included in the systematic review and 6 in meta-analysis. The pooled analysis of the 6 studies showed no significant differences in PSA levels in subjects treated with lycopene or tomato extract containing lycopene (WMD= -0.12 ng/ml; 95% CI: -0.62, 0.38 ng/ml; P = 0.64) compared to the control. CONCLUSION: Overall, tomato extracts or lycopene treatment yielded no significant effect on PSA level compared to the control. However, more consistent clinical trials, with larger sample sizes, are required to better discern the actual effect of tomato extract or lycopene on PSA level.

Zinc in depression: From development to treatment: A comparative/ dose response meta-analysis of observational studies and randomized controlled trials.

BACKGROUND: A previous meta-analysis suggested that zinc status may be linked to depression status. However, it remains unclear whether zinc status can predict the risk of depression development, or whether the monotherapy of zinc is superior to the combination of zinc supplementation and antidepressant medications in the treatment of depression. Therefore, this meta-analysis aimed to clarify the impact of zinc status and supplementation on depression development and status across all available evidence. METHODS: PubMed, EMBASE, Scopus, and ISI web of science were searched, up to 14 May 2020, for relevant publications. Pooled relative risks (RRs) with 95% confidence intervals (CI) in observational studies, and mean and standard deviation (SD) for the change in depression score in RCTs were calculated using a random-effects model. RESULTS: The meta-analysis of RCTs indicated that zinc supplementation significantly lowered depressive symptom scores of depressed patients [weighted mean difference (WMD = -4.15 point; 95% CI: -6.56, -1.75 point; P < 0.01)], and the improvement in depression status occurred only when zinc supplementation was prescribed as a monotherapy. The cohort studies showed that the highest level of zinc intake was associated with a 28% reduced risk of depression (RR: 0.66; 95% CI: 0.50, 0.82; I2 = 13.90). Dose-response analyses revealed a significant non-linear effect of baseline mood status on depression score. CONCLUSION: Current evidence from observational studies and RCT's supports the potential benefits zinc to reduce the risk of, and alleviate, depression. However, further trials are needed to confirm the beneficial effect of zinc as a monotherapy versus adjunctive therapies.

The effect of vitamin D supplementation on serum levels of fibroblast growth factor- 23: A systematic review and meta-analysis of randomized controlled trials.

Previous studies of the effect of vtamin D on serum levels of fibroblast growth factor- 23 (FGF-23) have yeilded an inconsistent findings. This systematic review and meta-analysis of randomized controlled trials (RCTs) sought to investigate the effect of vitamin D supplementation on serum levels of FGF-23. PubMed, Scopus, ISI Web of Science, and the Cochrane Library were searched, from database inception to November 2020, for RCTs that evaluated the effects of native or active vitamin D supplementation on serum levels of FGF-23 in adults. Weighted mean difference (WMD) were calculated and random effects meta-analysis was used to estimate the overall effects. Twenty-seven trials were included in the meta-analysis. Supplementation with native vitamin D (23 studies, n = 2247 participants; weighted mean difference [WMD] = 0.5 pg/mL, 95 % CI: -0.52 to 1.51, P = 0.33; I2 = 29.9 %), and active vitamin D (5 studies, n = 342 participants, WMD = 29.45 pg/mL, 95 % CI: -3.9 to 62.81, P = 0.08; I2 = 99.3%) had no significant effects on serum FGF-23 concentration. In subgroup analyses, supplementation with ergocalciferol (3 studies, n = 205 participants; WMD = 18.27 pg/mL, 95 % CI: 5.36-31.17, P = 0.006), and daily dosing regimens (9 studies, n = 1374 participants; WMD = 0.41 pg/mL, 95 % CI: 0.22 to 0.59, P < 0.001) increased serum FGF-23 levels compared to control. Overall, our findings revealed no significan effect of vitamin D supplementation on serum FGF-23 concentration. However, further high quality, large-scale studies are needed to better elucidate this relationship.

Effect of enteral immunomodulatory nutrition formula on mortality and critical care parameters in critically ill patients: A systematic review with meta-analysis.

BACKGROUND: Enteral immunomodulatory nutrition is recommended as an adjuvant therapy for patients in intensive care units (ICU), but its effectiveness is incompletely understood. AIM: The aim of this review was to examine the effect of a commonly used immunomodulatory formula-omega-3 fatty acids, γ-linolenic acid, and antioxidants-on clinical outcomes and mortality risk in critically ill patients. DESIGN: Systematic review and meta-analysis of randomized controlled trials (RCTs). METHOD: PubMed, Scopus, and Institute for Scientific Information (ISI) Web of Knowledge databases were searched until 18 February 2021. RCTs that used the immunomodulatory formula in the ICU were included. RESULTS: Ten RCTs (1166 participants) were included in the meta-analysis. The immunomodulatory formula reduced the duration of ICU stay weighted mean difference [(WMD): -2.97 days; 95%CI: -5.59, -0.35)], mechanical ventilation (WMD = -2.20 days, 95%CI: -4.29, -0.10), sequential organ failure assessment and multiple organ dysfunction scores (Hedge's g: -0.42 U/L; 95% CI: -0.74, -0.11), decreased 8-day overall mortality risk (RR = 0.74, 95% CI: 0.58, 0.91), and extended the ICU-free days (WMD: 4.06 days, 95% CI: 0.02, 8.09). The improvement in respiratory function and reduction in mortality risk was more in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Furthermore, the reduction in mechanical ventilation and mortality risk was more evident in older (>60 years) vs young adults. CONCLUSION AND RELEVANCE TO CLINICAL PRACTICE: Taken together, the immunomodulatory formula may enhance clinical practice for critical care nurses, such that the prevalence and/or susceptibility to secondary conditions commonly encountered in the ICU (ie, ALI and ARDS) could be attenuated, ultimately allowing critical care nurses to focus their care on the primary reason for which a patient is in the ICU. The study protocol was registered in PROSPERO.

The effect of vitamin C supplementation on mood status in adults: a systematic review and meta-analysis of randomized controlled clinical trials.

OBJECTIVE: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to clarify the effect of vitamin C supplementation on mood in both depressed and non-depressed populations. METHODS: A systematic search of PubMed, EMBASE, ISI web of science and Scopus databases was conducted, from inception to 1 March 2020. Random-effects meta-analyses were used to estimate the effect size (as Hedge's g) of vitamin C supplementation on depressive symptoms. RESULTS: Finding from 10 trials with 836 participants revealed no significant improvement in mood status in overall analysis (n = 10, Hedge's g = 0.09; 95% confidence interval: -0.15 to 0.33; P = 0.465). However, subgroup analysis showed beneficial effects of vitamin C supplementation in patients who were not prescribed antidepressants (subclinical depressed) (n = 5, Hedge's g: -0.18; 95% CI: -0.35, -0.01, P = 0.041; I2 = 0.00%,). CONCLUSIONS: Although no significant effect on mood status was observed in overall population, this meta-analysis tentatively suggests that vitamin C may produce mood-elevating effects in patients with subclinical depression. Further research is recommended to reach a firm conclusion. PROTOCOL REGISTRATION: The study protocol was registered in the international prospective register of systematic reviews database (http://www.crd.york.ac.uk/PROSPERO, registration no: CRD42018086677).

Zinc Supplementation Might Not Affect Serum Leptin and Adiponectin Levels in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials.

BACKGROUND: Zinc as one of the important trace elements in human health has been suggested to be a supplement for modifying the level of adipokines, whereas findings from studies have been inconsistent. This study aimed to systematically review the evidence provided by randomized controlled trials (RCTs) regarding the effect of zinc supplementation on serum adipokines levels. METHODS: PubMed, Google Scholar, Web of Science, and Scopus were systematically searched up to June 2019. The mean differences and their corresponding standard deviations (SDs) of changes in serum adipokines levels were used as effect size. RESULTS: Eight eligible RCTs (leptin n=6, adiponectin n=3) were included in the current study. There were no significant changes in serum leptin levels [weighted mean difference (WMD) =0.60 ng/ml, 95% confidence interval (CI): -1.78, 2.99; I-squared (I2) = 64.3%] and adiponectin levels (WMD = 1.09 ng/ml, 95% CI: -0.76, 3.18, I2 = 78.8%) following zinc supplementation compared to placebo group. These findings did not change after considering several subgroups including gender, study duration, health status, body weight and the type of zinc used for supplementation. CONCLUSION: No evidence was found to support the efficacy of dietary zinc supplements on serum levels of adipokines. Further, high-quality, long-term controlled clinical trials are warranted to confirm these findings.

The effect of vitamin D supplementation on insulin-like growth factor-1: A systematic review and meta-analysis of randomized controlled trials.

PURPOSE: There is equivocality regarding the interaction between vitamin D and insulin-like growth factor-1 (IGF-1). Thus, the aim of this study was to elucidate the effect of vitamin D supplementation on serum levels of IGF-1 by conducting a systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: PubMed, Scopus, and ISI Web of Science databases were searched up to May 2019 for RCTs that evaluated the effect of vitamin D supplementation on IGF-1 levels. Mean and standard deviation changes of IGF-1 in each treatment group were considered for analysis and pooled using random-effect model. Risk of bias for included studies was assessed by the Cochrane scale and the NutriGrade approach was applied to evaluate the quality of evidence. RESULTS: Six trials (n = 773 participants) were included in the meta-analysis. Compared with control group, vitamin D supplementation yielded no significant effect on serum level of IGF-1 (weighted mean difference [WMD] =4.66 ng/ml, 95 % CIs: -6.72 to 16.03, P = 0.42, I2 = 74.8, P-heterogeneity = 0.001). Additionally, no meaningful changes were observed in subgroup analyses. CONCLUSION: The evidence from the limited number of published trials does not convincingly show that vitamin D supplementation elicits any clinically relevant effects on IGF-1 levels. More high-quality studies are needed to reach a consensual conclusion in this area.

Zinc Supplementation and Body Weight: A Systematic Review and Dose-Response Meta-analysis of Randomized Controlled Trials.

The aim of this study was to determine the effect of zinc supplementation on anthropometric measures. In this systematic review and dose-response meta-analysis, we searched PubMed, Scopus, ISI Web of Science, and the Cochrane Library from database inception to August 2018 for relevant randomized controlled trials. Mean differences and SDs for each outcome were pooled using a random-effects model. Furthermore, a dose-response analysis for zinc dosage was performed using a fractional polynomial model. Quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Twenty-seven trials (n = 1438 participants) were included in the meta-analysis. There were no significant changes in anthropometric measures after zinc supplementation in the overall analysis. However, subgroup analyses revealed that zinc supplementation increased body weight in individuals undergoing hemodialysis (HD) [3 trials, n = 154 participants; weighted mean difference (WMD) = 1.02 kg; 95% CI: 0.38, 1.65 kg; P = 0.002; I2 = 11.4%] and decreased body weight in subjects who are overweight/obese but otherwise healthy (5 trials, n = 245 participants; WMD = -0.55 kg; 95% CI: -1.06, -0.04 kg; P = 0.03; I2 = 31.5%). Dose-response analyses revealed a significant nonlinear effect of supplementation dosage on BMI (P = 0.001). Our data suggest that zinc supplementation increases body weight in patients undergoing HD and decreases body weight in individuals who are overweight/obese but otherwise healthy, although after normalization for study duration, the association observed in subjects who are overweight/obese disappeared. Although more high-quality studies are needed to reach a definitive conclusion, our study supports the view that zinc may be associated with body weight.

Effect of probiotic and synbiotic supplementation on inflammatory markers in health and disease status: A systematic review and meta-analysis of clinical trials.

The current systematic review and meta-analysis investigated the effect of probiotic/synbiotic on a wide range of inflammatory and anti-inflammatory markers in healthy and various disease conditions. PubMed, SCOPUS and Web of Science databases were searched. All clinical trials which investigated the effect of oral administration of probiotic or synbiotic on inflammatory markers (C-reactive protein (CRP), interleukin (IL) 1ß, IL-4, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor (TNF) α, interferon (IFN) γ and transforming growth factor (TGF) ß) for more than one week with concurrent control groups were included. One-hundred sixty seven publications was analysed. Results were as follows: CRP decreased in healthy, metabolic disorders, inflammatory bowel disease (IBD), arthritis and critically ill condition but not in renal failure. IL-1B: no change in healthy subjects and arthritis. TNF-α: decreased in healthy, fatty liver, IBD and hepatic cirrhosis, no change in diabetes, metabolic syndrome (MS) + PCOS (polycystic ovary syndrome) and arthritis. IL-6: no change in healthy, metabolic disorders and arthritis, increased in cirrhosis and renal failure, decreased in PCOS + MS. IL-10: no change in healthy, IBD and metabolic disorders, increased in arthritis. IL-4, IL-8, IL-12, IFN-g and TGF-b: no change in healthy subjects. In conclusion, probiotic/synbiotic decreased some of the inflammatory markers. The intervention was most effective in CRP and TNF-α reduction in healthy or disease state. Moreover, the intervention decreased inflammation most effectively in the following disease conditions, respectively: IBD, arthritis, fatty liver. PROSPERO REGISTRATION NUMBER: CRD42018088688.

Effects of zinc, vitamin D, and their co-supplementation on mood, serum cortisol, and brain-derived neurotrophic factor in patients with obesity and mild to moderate depressive symptoms: A phase II, 12-wk, 2 × 2 factorial design, double-blind, randomized, placebo-controlled trial.

OBJECTIVE: The aim of this study was to investigate the effects of zinc, vitamin D, and their co-supplementation versus placebo on changes in the Beck Depression Inventory II (BDI-II) score, serum cortisol level, and brain-derived neurotrophic factor (BDNF) in obese/overweight patients with depressive symptoms. METHOD: This 2 × 2 factorial, double-blind, randomized, placebo-controlled trial with obese/overweight patients with depressive symptoms was conducted in the Endocrinology and Metabolism Research Center (EMRC), Vali-Asr, Emam Khomeini Hospital between July 2016 and February 2017. The intervention period was 12 wk. There were 140 randomized participants who were obese or overweight (mean ± SD, 38.35± 6.70 y of age; mean ± SD body mass index, 30.1 ± 3.78 kg/m2) with BDI ≥ 10. Participants were randomly assigned to one of four groups in a 1:1:1:1 ratio: 2000 IU/d vitamin D + zinc placebo; 30 mg/d zinc gluconate + vitamin D placebo; 2000 IU/d vitamin D + 30 mg/d zinc gluconate; or vitamin D placebo + zinc placebo for 12 wk. RESULTS: We analyzed 125 participants, and a significant decrease in BDI-II was found among those who received zinc, vitamin D, or joint zinc-vitamin D supplements compared with the placebo group (P < 0.001). Zinc was significantly more effective than vitamin D on decreasing the depression score. Supplementation with zinc, vitamin D, or a combination of the two had no significant effects on serum cortisol (P = 0.974) or BDNF (P = 0.076). Fifteen patients discontinued participation owing to pregnancy (n = 1), severe anemia (n = 1), and unspecified unwillingness to continue (n = 13). CONCLUSION: Supplementation with zinc, vitamin D, or in combination for 12 wk yielded significant beneficial effects on the BDI-II score in obese or overweight patients with BDI-II ≥10.

The effect of saffron supplementation on blood glucose and lipid profile: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Despite several studies about the effects of saffron supplementation on serum concentrations of lipid and glucose profiles, no systematic study had summarized the findings. Therefore, we conduct current study to systematically summarize findings from studies about the effect of saffron supplementation on serum levels of glucose and lipid profiles and to do a meta-analysis, if possible. METHODS: A systematic literature search was conducted for clinical trials published in PubMed, SCOPUS, EMBASE, Cochrane's Library and ISI Web of Science from the beginning to 22 February 2019. All randomized clinical trials on the effect of saffron supplementation on serum concentrations of lipid and glucose profiles were included. RESULTS: In overall, six studies were included in the current study. Pooled analysis of six studies for the effect of saffron on serum TG, TC and FBG concentrations and of five studies for LDL and HDL, showed a significant reduction in TG (WMD: -8.93 mg/dl; 95% CI: -16.49 to -1.37, P = 0.02) and TC levels (WMD: -5.72 mg/dl; 95% CI: -11.10 to -0.34, P = 0.03), a significant increase in HDL levels (WMD: 2.7 mg/dl; 95% CI: 0.22 to 5.18, P = 0.03), and no significant effect on LDL (WMD: -2.30 mg/dl; 95% CI: -11.73 to 7.13, P = 0.63) and FBG levels (WMD: -5.30 mg/dl; 95% CI: -14.20 to 3.60, P = 0.51). CONCLUSION: We found a significant reduction in serum concentrations of TC and TG and a significant increase in serum levels of HDL following supplementation with saffron. Saffron supplementation had no significant influence on serum FPG and LDL concentrations.