A comparison of the effects of cinnamon, ginger, and metformin consumption on metabolic health, anthropometric indices, and sexual hormone levels in women with poly cystic ovary syndrome: A randomized double-blinded placebo-controlled clinical trial.

Background/objectives: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in women that can alter blood glucose, lipid profile and sexual hormonal level. Therefore, the evaluation of potential therapeutic agents in this population is important. The aim of the study was to determine the effects of cinnamon, ginger, and metformin intake on improvement of sex hormones level, metabolic health (lipid profiles, insulin level and fasting blood glucose) and anthropometric indices (weight, body mass index (BMI), etc.) in women with PCOS. Methods: A total of 100 women with PCOS were randomly assigned to one of the following four groups: cinnamon (500 mg of cinnamon, 3 × day), ginger (500 mg of ginger, 3 × day), metformin (500 mg of metformin 3 × day) or placebo. However, 17 participants were excluded for various reasons and consequently, 83 participants were considered for analysis. Sexual hormones, anthropometrics, glycemic and lipid markers were evaluated before and after the 8-week intervention. Results: Weight and BMI decreased significantly in all intervention groups. The consumption of metformin and cinnamon significantly decreased insulin resistance (HOMA-IR) in comparison to the placebo and ginger groups (P < 0.05). Moreover, a significant decrease in FSH (follicle-stimulating hormone) and LH (Luteinizing hormone) levels were observed in the ginger compared to the placebo group. While metformin and cinnamon significantly lowered testosterone levels (P < 0.05), none of the groups experienced a significant change in DHEA (dehydroepiandrosterone). Conclusion: Our findings suggest that in women with PCOS, cinnamon supplementation causes similar reductions in insulin resistance and testosterone level to that of metformin. Ginger supplementation decreased FSH and LH, hormonal effects not seen following metformin consumption. Overall, cinnamon and ginger supplementations may potentially be used as alternative treatment in women with PCOS. Clinical trial registration: [https://www.irct.ir/trial/28548], identifier [IRCT20171227038105N1].

Meta-analysis of vitamin D supplementation and hemoglobin concentration: methodological faults obscure the interpretation of the data.

We read the review by Arabi et al. with great interest which tried to examine the effects of vitamin D supplementation on hemoglobin concentration. It seems that the article suffers from fundamental methodological issues and the conclusions are likely to be erroneous. In this regard, we would like to ask the authors to address the mentioned limitations and to update the analysis in order to provide robust and trustful results. We are concerned that such meta-analyses may lead to the biased findings and conclusions.

Did Iranians change their eating behavior following COVID-19 outbreak?

BACKGROUND: Significant lifestyle changes have been reported after COVID-19 outbreak. The present study aimed at investigating changes in dietary habits in response to the COVID-19 outbreak in an Iranian population sample. MATERIALS AND METHODS: In this cross-sectional study, the dietary habits of Iranian adults were assessed before and during the COVID-19 outbreak. Consumption of different food groups such as meats, dairy, fruits, vegetables, seeds, and nuts was assessed using a digital questionnaire which was shared on social media platforms. For the statistical analysis, the Wilcoxon signed-rank test was used. RESULTS: In this online survey, 1553 questionnaires were completed. The results showed that the reported consumption of protein-rich foods increased (P < 0.05), but fish and dairy consumption showed a significant reduction (P = 0.006 and <0.001, respectively). There was a significant reduction in reported fast-food consumption (P < 0.001). Fruits and vegetables (P < 0.001), natural fruit juices (P < 0.001), and water (P < 0.001) were consumed more frequently. Individuals also consumed more vitamin and mineral supplements (P < 0.001) including those containing Vitamin D. CONCLUSION: During the COVID-19 pandemic, participants reported a significant change in their dietary habits and intake of supplements. Higher intakes of meats, protein-rich foods, fruits, vegetables, and nutritional supplements and lower intakes of fish, dairy, and fast foods were reported.

Flaxseed supplementation on glucose control and insulin sensitivity: a systematic review and meta-analysis of 25 randomized, placebo-controlled trials.

Context: The results of human clinical trials investigating the effects of flaxseed on glucose control and insulin sensitivity are inconsistent. Objective: The present study aimed to systematically review and analyze randomized controlled trials assessing the effects of flaxseed consumption on glycemic control. Data Sources: PubMed, Medline via Ovid, SCOPUS, EMBASE, and ISI Web of Sciences databases were searched up to November 2016. Study Selection: Clinical trials in which flaxseed or its products were administered as an intervention were included. Data Extraction: The outcomes were fasting blood glucose, insulin concentration, insulin resistance (HOMA-IR), insulin sensitivity (QUIKI), and hemoglobin A1c (HbA1c). Results: A total of 25 randomized clinical trials (30 treatment arms) were included. Meta-analysis suggested a significant association between flaxseed supplementation and a reduction in blood glucose (weighted mean difference [WMD], -2.94 mg/dL; 95%CI, -5.31 to - 0.56; P = 0.015), insulin levels (WMD, -7.32 pmol/L; 95%CI, -11.66 to -2.97; P = 0.001), and HOMA-IR index (WMD, -0.49; 95%CI,: -0.78 to - 0.20; P = 0.001) and an increase in QUIKI index (WMD, 0.019; 95%CI, 0.008-0.031; P = 0.001). No significant effect on HbA1c (WMD, -0.045%; 95%CI, -0.16 to - 0.07; P = 0.468) was found. In subgroup analysis, a significant reduction in blood glucose, insulin, and HOMA-IR and a significant increase in QUIKI were found only in studies using whole flaxseed but not flaxseed oil and lignan extract. Furthermore, a significant reduction was observed in insulin levels and insulin sensitivity indexes only in the subset of trials lasting ≥12 weeks. Conclusions: Whole flaxseed, but not flaxseed oil and lignan extract, has significant effects on improving glycemic control. Further studies are needed to determine the benefits of flaxseed on glycemic parameters.

Resveratrol supplementation and plasma adipokines concentrations? A systematic review and meta-analysis of randomized controlled trials.

The results of human clinical trials have revealed that the effects of resveratrol on adipokines are inconsistent. Our objective was to elucidate the role of resveratrol supplementation on adipokines through a systematic review and a meta-analysis of available randomized placebo-controlled trials (RCTs).1 The search included PubMed-MEDLINE, SCOPUS and ISI web of sciences database till up to 6th November 2016. Weight mean differences (WMD)2 were calculated for net changes in adipokines using fixed-effects or random-effects models; meta-regression analysis and publication bias were conducted in accordance with standard methods. Nine RCTs with 11 treatment arms were eligible for inclusion in this systematic review and meta-analysis. Meta-analysis of data from 10 treatment arms showed a significant change in plasma adiponectin concentrations following resveratrol supplementation (WMD: 1.10µg/ml, 95%CI: 0.88, 1.33, p<0.001); Q=11.43, I2=21.29%, p=0.247). There was a significant greater adiponectin-reducing effect in trials with higher than or equal to 100mg/day (WMD: 1.11µg/ml, 95%CI: 0.88, 1.34, p<0.001), versus those with less than 100 mg/day dosage (WMD: 0.84µg/ml, 95%CI: -0.62, 2.31, p=0.260). Meta-analysis of data from 5 treatment arms did not find any significant change in plasma leptin concentrations following resveratrol supplementation (WMD: 3.77ng/ml, 95% CI: -2.28, 9.83, p=0.222; Q=8.00, I2=50.01%). Resveratrol significantly improves adiponectin but does not affect leptin concentrations. Additional studies are required to further evaluate the potential benefits of resveratrol on adipokines in humans.