Vitamin D protects against depression: Evidence from an umbrella meta-analysis on interventional and observational meta-analyses.

Meta-analyses of interventional and observational studies investigating the efficacy and the relationship between vitamin D and depression provided inconsistent results. The current umbrella meta-analysis was conducted to assess the available evidence and provide a conclusive outcome in this regard. The following international databases were systematically searched till March 2022: PubMed, Scopus, Embase, Web of Science, and Google Scholar. Random-effects model was carried out to calculate the pooled point estimates and their respective 95 % confidence intervals (CI). Ten meta-analyses of randomised controlled trials (RCTs) revealed significant reduction in depression symptoms comparing participants on vitmain D supplements to those on placebo (Pooled standardised mean difference: - 0.40; 95 % CI: - 0.60, - 0.21, p < 0.01: I2 = 89.1 %, p < 0.01). Four meta-analyses of cohort studies (with one having two subgroups) revealed that participants with lower levels of serum vitamin D were at increased odds of depression than those with higher levels of serum vitamin D (Pooled odds ratio: 1.60; 95 % CI: 1.08, 2.36, p < 0.01; I2 = 91.3 %, p < 0.01). The present umbrella meta-analysis confirms the potential benefits of vitamin D supplementation and higher serum vitamin D levels in reducing the development and symptoms of depression.

Probiotics as an effective therapeutic approach in alleviating depression symptoms: an umbrella meta-analysis.

Growing evidence has suggested that the consumption of probiotics can decrease depressive symptoms. However, even the results of meta-analyses are conflicting. In this regard, we performed an umbrella meta-analysis and proposed the decisive impacts of probiotics on depressive symptoms. The following international databases were searched up to July 2021: PubMed/Medline, Web of Science, Scopus, EMBASE, and Google Scholar. Meta-analyses investigating the impact of supplementation of probiotics on depression symptoms in adults were included. According to the studies, random-effects model was used to perform the analysis. Subgroup analysis was performed by dosage of probiotics, duration of supplementation and total sample size. Publication bias was assessed using Egger's, Begg's and visual inspection of funnel plot. Ten meta-analyses (n = 8886 participants) were included in study. The pooled data indicated that probiotic supplementation significantly reduced depression symptoms (ES= -1.41; 95% CI: -2.53, -0.30, p = 0.016; I2 = 99.4, p = <0.001). Subgroup analysis of studies with intervention duration >8 weeks and dosage >10 × 109 CFU demonstrated a more robust effect of probiotics on decreasing depression symptoms. There was also significant between-study heterogeneity in which dosage was identified as source of it. The results of present umbrella meta-analysis suggest administration of probiotics for relieving depression symptoms for >8 weeks with dosage of >10 × 109 CFU.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2051164.

High use of non-hydrogenated plant source oils and mayonnaise sauce increase the risk of Parkinson disease.

Objectives: This study aimed to assess the contribution of edible/cooking oils and mayonnaise sauce in the severity, motor and non-motor symptoms, and risk of Parkinson's disease (PD).Methods: In this study, 120 patients with PD and 50 healthy individuals participated. The frequency and quantity of edible/cooking oils including animal and plant source oils (hydrogenated and nonhydrogenated) and mayonnaise sauce used by participants were determined using a food frequency questionnaire. The severity of PD was determined by the Unified Parkinson's Disease Rating Scale (UPDRS).Results: Patients with PD had lower use of hydrogenated plant-based oil (HPO) (p < 0.001) and animal oils (p < 0.001) but had higher use of non-hydrogenated plant-based oil (NHPO) (p < 0.001), olive oil (p = 0.02), and mayonnaise sauce (p < 0.001) compared with the healthy subjects. Use of each unit HPO reduced 4% the odds of PD (p = 0.01). The odds of PD increased 20% by each unit increase in NHPO usage (p = 0.001), 49% by olive oil (p = 0.02), and 127% by mayonnaise sauce (p = 0.004) intake. According to receiver operator characteristics curve analysis, mayonnaise sauce and NHPO had the largest area under the curve in predicting PD. Intake of animal oil was positively correlated with total score of UPDRS (p = 0.05) and motor symptoms (p = 0.04). Intake of butter was positively correlated with total score of UPDRS (p = 0.047), nonmotor aspects of experiences of daily living (p = 0.02), and motor examination (p = 0.02).Discussion: The findings indicate that high intake of HPO reduces, while high intake of NHPO, olive oil, and mayonnaise sauce increases the odds of PD.

Saffron, as an adjunct therapy, contributes to relieve depression symptoms: An umbrella meta-analysis.

BACKGROUND: Saffron is a traditional herbal medicine that has been used to treat various ailments such as depressive mood. However, the findings of several meta-analyses regarding anti-depressive properties of saffron (Crocus sativus L.) are controversial. The current umbrella meta-analysis was carried out to determine the magnitude and direction of saffron administration on depression. METHODS: Relevant studies were searched in international databases including PubMed, Scopus, EMBASE, Web of Science, and Cochrane Central Library up to June 2021. Meta-analysis studies investigating the effects of saffron on depression were considered to include in the study. Random-effects model was used to perform the meta-analysis. Additional analyses including subgroup and sensitivity analyses were carried out. RESULTS: Overall, 7 meta-analyses were included in the study. The results demonstrated that the consumption of saffron resulted in a significant reduction in BDI scores (ES: -3.87; 95% CI: -5.27, -2.46). However, saffron did not change the HAMD scores (ES: -2.10; 95% CI: -5.05, 0.86, p = 0.164) and mixed scores (HAM-D/BDI/DASS) (ES: 0.02; 95% CI: -0.39, 0.43,p = 0.941). CONCLUSION: Present umbrella meta-analysis demonstrated that saffron intake might contribute to alleviation of depression disorder, however, it cannot be considered as a single therapeutic approach to treat depression.

Dietary approach to stop hypertension (DASH), but not Mediterranean and MIND, dietary pattern protects against Parkinson's disease.

The neuroprotective effects of dietary patterns have been reported in previous studies. This study aimed to examine the association between the dietary approach to stop hypertension (DASH), the Mediterranean diet (MeDi), and the Mediterranean-DASH intervention for neurodegenerative delay (MIND) with the severity and risk of Parkinson's disease (PD). In this comparative cross-sectional study, 120 patients with PD and 50 healthy participants participated. Adherence to DASH, MeDi, and MIND dietary patterns was determined according to the dietary intake data using a food frequency questionnaire (FFQ). The Severity of PD was determined by the Unified Parkinson's Disease Rating Scale (UPDRS). The mean score of the DASH was significantly lower in the PD group compared to the healthy group (p = .006), but the mean score of MeDi and MIND did not significantly differ between the two groups (p > .05). Also, the mean score of the DASH was significantly lower in men than in women in the healthy group (p = .018). High adherence to the DASH diet decreased the risk of PD by 15% (OR = 0.856, 95% CI: 0.751, 0.976, p = .020). Participants in quartiles 3 and 4 of the DASH dietary pattern had 86% (p = .003) and 87% (p = .007), respectively, lower risk of PD. MeDi and MIND diets were not significantly associated with the risk of PD. There was no significant association between dietary patterns and the severity of PD. The findings indicate that high adherence to the DASH dietary pattern may protect against PD.

What Dietary Vitamins and Minerals Might Be Protective against Parkinson's Disease?

BACKGROUND AND OBJECTIVE: Dietary constituents may affect the progression of Parkinson's disease (PD). This study aimed to assess the contribution of dietary intake of vitamins and minerals to the severity, motor and non-motor symptoms, and risk of PD. METHODS: In this case-control study, 120 patients with PD and 50 healthy participants participated. Dietary intake of vitamins and minerals was determined using a 147-item food frequency questionnaire. The severity of PD was determined by the Unified Parkinson's Disease Rating Scale (UPDRS). RESULTS: Patients with PD had lower intake of several vitamins and minerals including lycopene, thiamine, vitamin B6, vitamin B12, pantothenic acid, magnesium, zinc, manganese, selenium, chromium, and phosphorus, but had higher intake of α-tocopherol. High dietary intake of vitamin A, α-carotene, ß-cryptoxanthin, vitamin C, and α-tocopherol were correlated with increased odds of PD. High intake of lycopene, thiamin, vitamin B6, pantothenic acid, magnesium, zinc, manganese, chromium, and phosphorous correlated with reduced odds of PD. The predictive power of α-tocopherol concerning the risk of PD was stronger relative to other vitamins. Dietary intake of pantothenic acid was negatively correlated with PD severity and symptoms of motor examination and complication. The severity and motor symptoms of PD were also negatively correlated with ß-carotene, vitamin C, riboflavin, vitamin B6, and biotin intake. The UPDRS total score and motor symptoms in PD patients were negatively correlated with phosphorus, magnesium, zinc, manganese, and chromium, and strongly with potassium intake. CONCLUSION: The findings indicate that adequate dietary intake of vitamins and minerals may have a preventive effect on developing PD and progression of motor decline.

The effect of cinnamon supplementation on glycemic control in patients with type 2 diabetes or with polycystic ovary syndrome: an umbrella meta-analysis on interventional meta-analyses.

BACKGROUND: Several meta-analyses reported glycemic-lowering effects of cinnamon, while others reported conflicting findings. In the present study, we aimed to perform an umbrella meta-analysis of previous interventional meta-analyses on the effects of cinnamon on glycemic control in patients with type 2 diabetes (T2D) or with polycystic ovary syndrome (PCOS). METHODS: Relevant studies were searched in PubMed, Scopus, EMBASE, Web of Science, and Google Scholar up to June 2022. Meta-analyses of randomized clinical trials (RCTs) investigating the effects of cinnamon on glycemic indices including fasting plasma glucose (FPG), homeostatic model assessment for insulin resistance (HOMA-IR), insulin, and hemoglobin A1C (HbA1c) were included. Random-effects models were used to perform the umbrella meta-analysis and pool the weighted mean difference (WMD) or standardized mean difference (SMD) and their 95% confidence intervals (CI). RESULTS: Overall, 11 meta-analyses of RCTs were included. Cinnamon supplementation was effective in reducing serum FPG (WMD: -10.93 mg/dL; 95%CI: -16.22, -5.65; SMD: -0.86; 95%CI: -1.19, -0.52), insulin (WMD: -2.01 IU/mL; 95%CI: -3.96, -0.07; SMD: -0.61; 95%CI: -0.93, -0.30), HOMA-IR levels (WMD: -0.61; 95%CI: -0.91, -0.31; SMD: -0.78; 95%CI: -1.26, -0.30), and HbA1c (WMD: -0.10%; 95%CI: -0.17, -0.03). CONCLUSION: Cinnamon can be used as an anti-diabetic agent and an add-on treatment to control glycemic indices among patients with T2D or PCOS.

The effect of L-carnitine supplementation on lipid profile in adults: an umbrella meta-analysis on interventional meta-analyses.

Introduction: Previous meta-analyses investigating the therapeutic effects of L-carnitine on lipid profiles have demonstrated inconsistent results. The present umbrella meta-analysis aimed to investigate the impact of efficacy of L-carnitine on lipid profiles in adults. Methods: Databases including PubMed, Scopus, and Embase, Web of Science, and Google Scholar were searched up to June 2023. Meta-analysis was performed using a random-effects model. Results: Our results from thirteen meta-analyses indicated that L-carnitine supplementation significantly total cholesterol (TC) (ES = -1.05 mg/dL, 95% CI: -1.71, -0.39; p = 0.002), triglycerides (TG) (ES = -2.51 mg/dL; 95% CI: -3.62, -1.39, p < 0.001), and low-density lipoprotein-cholesterol (LDL-C) (ES = -4.81 mg/dL; 95% CI: -6.04, -3.59; p < 0.001). It also increased high-density lipoprotein-cholesterol (HDL-C) (ES: 0.66 mg/dL, 95% CI: 0.20, 1.12, p = 0.005) levels. Conclusion: The present umbrella meta-analysis suggests supplementation with L-carnitine in a dosage of more than 2 g/day can improve lipid profile. Thus, L-carnitine supplementation can be recommended as an adjuvant anti-hyperlipidemic agent.

Association of High Dietary Acid Load With the Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies.

Objective: This study aimed to determine the relationship between the high dietary acid load (DAL) and the risk of cancer. Methods: Five databases of PubMed, Web of Sciences, Scopus, Cochrane Library, and Google Scholar was searched to elicit original studies on humans, up to June 2021. Quality of the articles, risk of bias, and heterogeneity were assessed. A random-effects meta-analysis model was applied to estimate pooled effect size with a 95% confidence interval. Sensitivity analysis was performed using a fixed-effects model. Subgroup analyses were carried out based on gender, age, type of cancer, and type of DAL assessment indicator. Results: Seventeen effect sizes from 10 articles were included in the analysis. Overall, individuals with the highest DAL were associated with a 66% increased risk of cancer compared to those with the lowest DAL (p < 0.001]. The risk of cancer increased 41% (p < 0.001) and 53% (p = 0.03) by high PRAL and NEAP, respectively. High DAL was associated with 32% (p < 0.001) and 79% (p < 0.001) increased risk of breast and colorectal cancers, respectively. High DAL was associated with 32% (p = 0.001) and 76% (p = 0.007) increased risk of cancer incident in women and men, respectively. The risk of cancer incident increased 35% (p < 0.001) and 49% (p < 0.001) at age ≤ and > of 50, respectively. Conclusion: High DAL may be associated with a higher risk of cancer incidence not only in the whole studied population but also across cancer types, both genders, both DAL assessment indicators, and also among both high- and low-risk age groups for cancer.

Cinnamon, an effective anti-obesity agent: Evidence from an umbrella meta-analysis.

The evidence provided by meta-analyses on the beneficial impacts of cinnamon supplementation on anthropometric indices are still conflicting. Present study's aim was to evaluate the effects of cinnamon on obesity indices by an umbrella meta-analysis. The electronic databases including Web of Science, PubMed, EMBASE, Scopus were systematically searched up to March 2021. Data for the effects of cinnamon on anthropometric indices were collected from the meta-analyses. An umbrella meta-analysis was carried out using a random-effects model. The pooled effects of 7 meta-analyses showed that cinnamon supplementation significantly reduced body weight (ES: -0.67 kg; 95% CI: -0.99, -0.35, p Ë‚ .001), body mass index (ES: -0.45 kg/m2 ; 95% CI: -0.57, -0.33, p Ë‚ .001) in comparison to control group. However, the effects of cinnamon on waist circumference (ES: -1.05 cm; 95% CI: -2.26, 0.15, p = .087) were not considerable. According to results, cinnamon could be suggested as a complementary weight loss agent. Favorable results were obtained at a dose of ≥3 g/day. In this study, a comprehensive study was performed on meta-analyses performed on the effect of cinnamon on anthropometric indices. This study could be considered as a final conclusion about the effect of cinnamon on anthropometric indices. The results of this study showed that supplementation with cinnamon significantly reduces BMI and body weight. The impacts were greater in doses of ≥3 g/day and in PCOS patients. PRACTICAL APPLICATIONS: In this study, a comprehensive study was performed on meta-analyses performed on the effect of cinnamon on anthropometric indices. This study could be considered as a final conclusion about the effect of cinnamon on anthropometric indices. The results of this study showed that supplementation with cinnamon significantly reduces BMI and body weight. The impacts were greater in doses of ≥3 g/day and in PCOS patients.

Flaxseed Oil Supplementation Augments Antioxidant Capacity and Alleviates Oxidative Stress: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: Studies have reported controversial findings regarding the flaxseed oil effect on antioxidant status biomarkers. The present meta-analysis aimed to determine the impact of flaxseed oil on the serum level of biomarkers of oxidative stress. METHODS: A systematic search was conducted up to November 2020 on PubMed, Embase, Web of Science, Scopus, and Cochrane Central Library. Random-effects model was employed to perform meta-analysis. Subgroup analysis was carried out to determine the effect across different ranges of dosages and durations. RESULTS: Eight trials were included with a total sample size of 429 individuals with a mean age range of 25 to 70 years. The results indicated that flaxseed oil supplementation led to a significant decrease in malondialdehyde (MDA) levels (SMD: -0.52 µmol/L; 95% CI: -0.89, -0.15; P=0.006, I 2 = 71.3, P < 0.001) and increase in total antioxidant capacity (TAC) levels (WMD: 82.84 mmol/L; 95% CI: 19.80, 145.87; P=0.006, I 2 = 92.7, P < 0.001). No significant effect was observed on glutathione (GSH). CONCLUSION: Our findings revealed that flaxseed oil supplementation might play a beneficial role in the reinforcement of the antioxidant defense system and amelioration of oxidative stress in adults.