Beneficial effects of blueberry supplementation on the components of metabolic syndrome: a systematic review and meta-analysis.

Metabolic syndrome (MetS) is a combination of interconnected disorders that puts a heavy burden on society. This study investigated the impact of blueberry (BB) supplementation on components of MetS. A systematic search for studies in Embase, Science Direct, Cochrane and PubMed was done. Interventions for at least 2 weeks and studies which investigated the effects of BB on components of MetS in human subjects were included. 25 studies were eligible for inclusion in the review. 21 studies were included in the meta-analysis and the remaining 4 studies in the systematic review. The time range of the assessed studies was from 2007 to 2021. The results of the meta-analysis demonstrated that BB had no significant effect on waist circumference, body mass index (BMI), glycated hemoglobin (HbA1C), glucose level and homeostatic model assessment for insulin resistance (HOMA-IR); however, studies showed a significant improvement in systolic and diastolic blood pressure, triglycerides, total cholesterol, low-density lipoproteins (LDL), high-density lipoproteins (HDL) and insulin levels. In conclusion, the data in this meta-analysis show that BB supplementation is a beneficial option for the management of MetS in humans.

Effects of cumin (Cuminum cyminum L.) essential oil supplementation on metabolic syndrome components: A randomized, triple-blind, placebo-controlled clinical trial.

Prevalence of metabolic syndrome (MetS), as a major health problem, is increasing. Very limited data exist on the effect of Cuminum cyminum L. essential oil (CuEO) on MetS components. Accordingly, this study aimed to examine the effect of CuEO supplementation on anthropometric indices, glycemic control, blood pressure, lipid profile, and insulin resistance in patients with MetS. In a randomized, triple-blind, placebo-controlled clinical trial, 56 patients with MetS aged 18-60 years received either 75 mg CuEO or placebo soft gel thrice daily for 8 weeks. Anthropometric indices and biochemical measurements were assessed at baseline and end of the study. At the end of study, except for diastolic blood pressure (DBP), the other assessed variables were not significantly different between two groups. In intra group analysis, placebo and CuEO groups both had nonsignificant decrements in DBP (mean difference [MD] with 95% CI: -3.31 [-7.11, 0.47] and -1.77 [-5.95, 2.40] mmHg, respectively). However, DBP was significantly lower in CuEO compared with the placebo group at the end of study (81.41 ± 5.88 vs. 84.09 ± 5.54 mmHg, MD with 95% CI: -3.98 [-7.60, -0.35] mmHg, p < .05). The results indicated that CuEO does not have any effect on MetS components, except for DBP in patients with MetS.

The effect of cumin supplementation on metabolic profiles in patients with metabolic syndrome: A randomized, triple blind, placebo-controlled clinical trial.

Metabolic syndrome (MetS) is a cluster of interconnected serious disorders, which is a major health problem whose prevalence is increasing. Oxidative stress and inflammation contribute to the disease pathogenesis and its complications. The present study aimed to investigate the effect of Cuminum cyminum L. (which has antioxidant and anti-inflammatory properties) essential oil (CuEO) supplementation on inflammatory and antioxidant status in patients with MetS. In this clinical trial, 56 patients with MetS aged 18-60 years received either 75-mg CuEO or placebo soft gel, thrice daily, for 8 weeks. Data on anthropometric parameters, food consumption, tumor necrosis factor alpha, high-sensitivity C-reactive protein, superoxide dismutase (SOD), glutathione peroxidase, catalase, total antioxidant capacity (TAC), and malondialdehyde (MDA) were assessed at the beginning and at the end of the study. Compared with the placebo group, CuEO increased SOD (149.17; 95% CI, [67.93, 230.42]), TAC (0.24; 95% CI, [0.09, 0.38]) and decreased MDA (-0.36; 95% CI, [-0.66, 0.06]), (p < 0.01). In within-group analysis, CuEO led to 13.3% decrease in MDA and 6.7% increase in TAC levels (p < 0.04). The results indicated that CuEO supplementation can improve some antioxidative indices, as SOD and TAC, while decreasing MDA in patients with MetS.

Effect of vitamin D supplementation along with weight loss diet on meta-inflammation and fat mass in obese subjects with vitamin D deficiency: A double-blind placebo-controlled randomized clinical trial.

BACKGROUND & AIMS: Low serum 25-hydroxyvitamin D (25OHD) is common in obese people. Obesity is associated with a state of low-grade inflammation (meta-inflammation). There is an increasing evidence indicating that vitamin D has anti-adipogenic activity and immunoregulatory effect. This study aimed to assess the effect of vitamin D supplementation on meta-inflammation and fat mass in obese subjects with vitamin D deficiency. MATERIALS AND METHODS: In this double-blind placebo-controlled randomized clinical trial, 44 obese subjects with vitamin D deficiency (25OHD < 50 nmol/L) were assigned into vitamin D (a weight reduction diet + bolus weekly dose of 50 000 IU vitamin D) or placebo group (weight reduction diet + edible paraffin weekly) for 12 weeks. Weight, fat mass and serum levels of 25OHD, calcium, parathyroid hormone (PTH), monocyte chemoattractant protein-1 (MCP-1), interleukin-1ß (IL-1ß) and Toll-like receptor 4 (TLR4) were assessed before and after the intervention. RESULTS: Vitamin D supplementation resulted in significant increase of serum 25OHD level (P < 0.001), and significant decrease in PTH (P < 0.001), MCP-1 (P < 0.05), IL-1ß (P < 0.05) and TLR-4 (P < 0.05); compared to the baseline values in vitamin D group. Weight, BMI and fat mass decreased in both groups (P < 0.05). Between the groups, there were significant decrease in weight, fat mass, serum MCP-1 and PTH concentrations and significant increase in serum 25OHD concentrations after intervention with vitamin D supplementation compared to placebo (P < 0.05). CONCLUSIONS: Improvement in vitamin D status in obese subjects with vitamin D deficiency in combination with weight loss diet resulted in weight, fat mass and MCP-1 decrease. Weight loss and vitamin D supplementation may act synergistically to reduce levels of meta-inflammation.