Investigation of the probiotic supplement's effect on obese adults demonstrated a reduction in fasting insulin levels: a double-blind randomized clinical trial.

Purpose: Regarding the importance of obesity concerns and trying to help obese individuals, we planned to develop an effective probiotic formula for weight control. So, this double-blind randomized clinical trial study investigated the impact of probiotics supplementation on anthropometric and biochemical parameters in obese adults. Methods: In this study, 66 obese patients with BMI in the range of 30-40 kg/m2, were enrolled and randomly assigned to either the probiotic or placebo group. They all received advice to maintain a reduction in daily caloric intake and for 3 months received two unlabeled placebo or probiotic (Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus casei and Bifidobacterium langum) capsules per day. For each participant demographic and medical history questionnaire, semi-quantitative food frequency questionnaire (FFQ), and modifiable activity questionnaire (MAQ) were completed at the beginning of the study and anthropometric and biochemical measurements were done before and after intervention. Results: At the end of the trial 25 subjects in the probiotic group and 26 subjects in the placebo group were analyzed. After the intervention, in the probiotic group, the level of fasting insulin was reduced significantly (P < 0.05). Weight, body mass index, waist circumference, and hip circumference decreased within both groups. This reduction amount's mean was higher in the probiotic group. Also, total cholesterol, triglycerides, and LDL levels were decreased, but not statistically significant. Conclusion: This study may suggest the potential of this combined probiotic supplement for treating obesity and related metabolic disorders. However, further researches are warranted for a definitive determination of its properties.

Exploring the association between ultra-processed foods and COPD: a case-control study.

BACKGROUND: While it is known that the overconsumption of ultra-processed foods (UPFs) is associated with a heightened risk of respiratory ailments, the specific effects of UPF intake on COPD remain unclear. This study was designed to explore the potential link between COPD and the consumption of UPFs among adult individuals in Iran. METHODS: In this hospital-based case-control study conducted at Alzahra University Hospital in Isfahan, Iran, we enrolled 84 patients newly diagnosed with COPD, along with 252 healthy controls matched for age and sex. COPD was defined based on the results of spirometry tests, specifically when the forced expiratory volume per second (FEV1) was less than 80% or the ratio of FEV1 to forced vital capacity (FVC) was less than 70%. To evaluate the dietary intake of the participants, we utilized a validated food frequency questionnaire (FFQ) consisting of 168 items. Additionally, we gathered data on potential confounding factors using a pre-tested questionnaire. RESULTS: The mean ages for the case and control groups were 57.07 and 55.05 years, respectively. Our study found no significant association between the intake of ultra-processed foods (UPFs) and the likelihood of COPD, with an odds ratio (OR: 0.78, 95% CI: 0.34-1.77). This lack of association persisted even after adjusting for factors such as energy intake, sex, and age (OR: 0.48; 95% CI: 0.19-1.21). Further controlling for potential confounders like body mass index (BMI), physical activity, and smoking status did not alter this finding (OR: 0.367; 95% CI: 0.123-1.1008, P = 0.074). CONCLUSIONS: In our study, we observed no significant association between the intake of Ultra-Processed Foods (UPFs) and the odds of Chronic Obstructive Pulmonary Disease (COPD). This finding remained consistent even after adjusting for factors such as energy intake, sex, age, Body Mass Index (BMI), physical activity, and smoking status. Therefore, within the scope of our study, it appears that the consumption of UPFs does not significantly impact the likelihood of developing COPD. However, we recommend further research to deepen our understanding of the intricate relationship between dietary habits and respiratory health.

Snack consumption patterns and their associations with risk of incident metabolic syndrome: Tehran lipid and glucose study.

AIM: Few studies considered the association between snack patterns and metabolic abnormalities. Here we aimed to characterize the major snack patterns among Iranian adults and determine their association with the risk of metabolic syndrome (MetS). METHODS: This study was conducted on 1713 MetS-free adults who participated in the third phase of the Tehran Lipid and Glucose Study (TLGS). At baseline, dietary intake of snack was assessed using a validated 168-items food frequency questionnaire, and snack patterns were obtained by principal component analysis (PCA). Adjusted Hazard Ratios (HRs) and 95% confidence intervals (CIs) were calculated for the association of incident MetS with the extracted snack patterns. RESULTS: PCA identified five major snack patterns, defined as "healthy pattern", "low-fructose pattern", "high-trans pattern", "high-caffeine pattern" and "high-fructose pattern". Participants in the highest tertile of the "high-caffeine pattern" had lower risk of MetS (HR = 0.80, 95% CI = 0.65-0.99, P for trend = 0.032). Other snack patterns have not shown any significant association with MetS incidence. CONCLUSIONS: Our findings suggest that consuming a snack pattern with high loads of caffeine, defined as "High-caffeine pattern" in the present study, could reduce the risk of MetS in healthy adults. Further prospective studies are needed to more fully determine the association between snack patterns and MetS incidence.

Junk food consumption and psychological distress in children and adolescents: a systematic review and meta-analysis.

Background: Available evidence indicates that junk foods, defined as unhealthy foods with high-calorie and low-nutrient value, negatively affect mental and metabolic health of children. This study aimed to conduct a meta-analysis to clarify the association between junk food consumption and psychological distress in children and adolescents.Methods: A systematic literature search of relevant documents published in PubMed, Web of Science, and SCOPUS was conducted up to 2022. All observation studies which assessed association of junk foods and psychological distress in children and adolescents were included. Random-effect model was used to pool odds ratio (OR) and 95% confidence interval (CI) from individual studies. Subgroup meta-analysis was performed based on junk foods categories (sweet drinks, sweet snacks and snacks).Results: Data of 17 included articles on junk foods consumption in relation to depression, stress, anxiety, sleep dissatisfaction and happiness in children and adolescents were included in this systematic review. According to random effect model, the pooled OR in the highest vs. the lowest category of junk foods was 1.62 (95% CI: 1.35-1.95) for depression, 1.34 (95% CI: 1.16-1.54) for stress, 1.24 (95% CI: 1.03-1.50) for anxiety, 1.17 (95% CI: 1.05-1.30) for sleep dissatisfaction and 0.83 (95% CI: 0.75-0.92) for happiness. In subgroup meta-analysis, there were significant associations between different types of junk foods and psychological distress (P < 0.05).Conclusion: This meta-analysis showed that junk foods consumption was associated with increased odds of psychological distress in children and adolescents. These findings support the current recommendation of decreasing junk foods intake.

The effect of "moderately restricted carbohydrate" diet on gut microbiota composition and metabolic parameters in women with metabolic syndrome: a study protocol for a randomized controlled trial.

BACKGROUND: Metabolic syndrome (MetS) is a group of risk factors that increase the risk of death and a variety of chronic diseases. Recent studies have indicated that the imbalance of gut microbiota might contribute to development and progression of metabolic syndrome. Carbohydrate restriction in the diet has been proven to be one of the most effective methods in the management of metabolic syndrome, even in the absence of weight loss. However, no study has examined the effects of a carbohydrate-restricted diet on gut microbiota composition in metabolic syndrome patients. Thus, we will examine the effects of a "moderately restricted carbohydrate (MRC)" diet on gut microbiota, insulin resistance, and components of MetS among Iranian women. In addition, the stability of changes in dependent variables, including gut microbiota, will also be assessed. METHODS: This is a parallel randomized clinical trial in which 70 overweight or obese women aged 20-50 years with MetS will be randomly assigned to receive either MRC diet (42-45% carbohydrate, 35-40% fats) or a normal weight loss (NWL) diet (52-55% carbohydrate, 25-30% fats) for 3 months. Protein accounted for 15-17% of total energy in both diets. The quantity of gut microbiota including Firmicutes, Bacteroidetes, Bifidobacteria, Lactobacillus, Clostridium, Prevotella, Bacteroidetes, and Akkermansia muciniphila, as well as anthropometric, blood pressure, and metabolic parameters will be measured at study baseline and the end of trail. At the end of this phase, all participants will be placed on a weight maintenance diet for an additional 6 months. After following up study subjects in this duration, all dependent variables will be examined again to assess their stability over this period. DISCUSSION: To the best of our knowledge, this is the first randomized controlled trial investigating the effects of a moderately restricted carbohydrate diet on gut microbiota composition and several metabolic parameters during the weight loss and maintenance phases in women with MetS. TRIAL REGISTRATION: Iranian Registry of Clinical Trials ( www.irct.ir , IRCT20210307050621N1). Registered on May 31, 2021.

Association of periodontitis with lipid profile: an updated systematic review and meta-analysis.

Purpose: The aim of this updated version of the systematic review and meta-analysis was to assess the association of PD with lipid profile. Methods: A comprehensive literature search was done in electronic databases including PubMed, Web of Science, and Scopus until August 2021. Cross-sectional, case-control, and cohort studies investigating the relationship between PD and lipid profile were included. Screening, data extraction, and quality assessment were performed independently by two investigators. A random-effect model was used to pool the effect size. Odds ratio (OR) was used as effect size for the association of PD with Hyperlipidemia, and SMD was used for the association of PD with the mean level of lipid profile. Results: Overall, 34 documents met the inclusion criteria for this systematic review, and 31 were included for the meta-analysis. Sixteen studies were cross-sectional, 16 case-control, and two cohorts. Results of the random effect model showed that PD increased the odds of dyslipidemia by 15% (OR: 1.15, 95% CI: 1.04, 1.26). The Association of PD with low HDL, high LDL, hypertriglyceridemia, and hypercholesteremia was not statistically significant (P > 0.05). The mean level of HDL in patients with PD was significantly lower than in subjects without PD (SMD: -0.69, 95% CI: -1.11, -0.26). Moreover, the mean level of LDL, TC, TG in patients with PD was significantly higher than in subjects without PD (P < 0.05). Conclusions: This meta-analysis suggests that periodontitis is associated with an increased odds of dyslipidemia. Therefore, treating periodontitis may improve dyslipidemia, particularly HDL and triglyceride levels.

The effect of walnut consumption on cardiometabolic profiles of individuals with abnormal glucose homoeostasis: a systematic review and meta-analysis of clinical trials.

Findings on the effect of walnut consumption on cardiometabolic profiles in individuals with abnormal glucose homoeostasis are conflicting. We summarised earlier data in this regard. A systematic literature search of relevant reports published in Medline/PubMed, ISI web of Science, EMBASE, SCOPUS and Google Scholar up to October 2020 was conducted. Randomised trials that enrolled individuals with abnormal glucose homoeostasis in which the main intervention was walnut consumption were included. Abnormal glucose homoeostasis was defined as a spectrum of impaired glucose tolerance or pre-diabetic status that is associated with insulin resistance. Twelve studies were included in systematic review and eight in meta-analysis. No significant effect of walnut consumption on anthropometric measures, including weighted mean difference (WMD: -0·13; 95 % CI -0·64, 0·39 kg), BMI (-0·08; 95 % CI -0·47, 0·32 kg/m2) and waist circumference (0·01; 95 % CI -0·50, 0·52 cm) was observed. Although walnut intake did not influence on lipid profiles (including TAG, total- and HDL-cholesterol levels), individuals in the intervention group tended to have lower levels of LDL-cholesterol than those in the control group (-0·10; 95 % CI -0·20, 0·01 mmol/l; P = 0·06). Other cardiometabolic factors including markers of glycaemic control (fasting blood glucose and HbA1C levels), blood pressure and stimulus-adjusted response measure (a parameter of endothelial function) were not significantly affected. However, walnut consumption resulted in a significant increase in flow-mediated dilation (FMD) (0·93 %; 95 % CI 0·16, 1·71 %). Summarising earlier evidence, we found that walnut consumption might influence FMD and LDL-cholesterol levels in individuals with abnormal glucose homoeostasis. It did not affect other cardiometabolic profiles in these individuals.

Fish consumption during pregnancy and risk of allergic diseases in the offspring: A systematic review and meta-analysis.

Although several studies have reported the beneficial effects of maternal fish consumption on allergy diseases in the offspring, the findings are conflicting. We summarized earlier data on the association between maternal fish intake and risk of allergy diseases in the offspring through a meta-analysis. A systematic literature search of relevant reports published in Medline/PubMed, ISI web of Science, EMBASE, SCOPUS and Google Scholar prior to February 2020 was conducted. All observational studies (cross-sectional, case-control or cohort) that examined the relationship between intake of maternal fish and risk of allergy diseases in the offspring were considered. Duplicate and non-related studies were excluded. In total, 31 studies on maternal fish consumption and risk of allergic diseases in the offspring were included. Greater maternal fish intake was associated with a reduced risk of wheeze (Pooled effect size: 0.97; 95% CI: 0.96-0.99) and food allergy (0.75; 95% CI: 0.64-0.88). Maternal fish consumption was not associated with risk of asthma (pooled effect size: 0.99; 95% CI: 0.89, 1.11), eczema (pooled effect size: 0.93; 95% CI: 0.84, 1.03), allergic rhinitis (pooled effect size: 0.91; 95% CI: 0.75, 1.09), and inhalant allergy (pooled effect size: 0.86; 95% CI: 0.66, 1.13). In non-linear dose-response meta-analysis, increased intake of fish during pregnancy (at the level of 50 to 200 grams per week) was associated with a reduced risk of eczema (P non-linearity = 0.042). Meta-regression of included studies revealed an inverse linear association between maternal fish intake and risk of eczema; such that every additional 30-gram per week consumption of fish during pregnancy was associated with a 4% reduced risk of eczema. We found that fish intake during pregnancy was associated with a lower risk of wheeze, eczema and food allergy in children. No significant association was seen between maternal fish consumption and risk of offspring's asthma, allergic rhinitis, and inhalant allergy.

Adherence to Low Carbohydrate Diet in Relation to Chronic Obstructive Pulmonary Disease.

Purpose: Data on the link between adherence to low-carbohydrate diet (LCD) and odds of chronic obstructive pulmonary disease (COPD) are scarce. The current study aimed to investigate the relation between adherence to LCD and COPD in Iranian adults. Methods: In this hospital-based case-control study, we enrolled 84 newly-diagnosed COPD patients and 252 age and sex matched healthy controls in Alzahra University Hospital, Isfahan, Iran. COPD was defined based on findings of spirometry test (forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 70% or FEV1 < 80%). Dietary intakes of study participants were assessed using the validated Block-format 168-item FFQ. Data on potential confounders were also collected through the use of a pre-tested questionnaire. Results: Mean age of cases and controls were 57.7 and 55.07 years, respectively. Adherence to LCD was inversely associated with odds of COPD (0.35; 95% CI: 0.16-0.75). This inverse association did not alter after controlling for age, sex, and energy intake (0.42; 95% CI: 0.19-0.93). Adjustments for other potential confounders, including dietary intakes, smoking, and educational status, did not affect these findings; such that those in the highest quintile of LCD score were 64% less likely to have COPD than those in the lowest quintile (OR: 0.36; 95% CI: 0.13-0.99). Conclusion: We found an inverse association between adherence to LCD and odds of COPD. The association remained statistically significant even after taking other potential confounders, including socioeconomic characteristic and dietary intakes into account.

Probiotics as a New Regulator for Bone Health: A Systematic Review and Meta-Analysis.

Despite the proposed role of the gut microbiota-bone axis, findings on the association between probiotic consumption and bone health are conflicting. This systematic review aimed to assess the effect of probiotic consumption on bone health parameters. A systematic literature search of relevant reports published in PubMed/Medline, Web of Science, SCOPUS, EMBASE, and Google scholar before December 2020 was conducted. All clinical trials or experimental studies, which examined the relationship between probiotic consumption and bone health parameters, were included. No limitation was applied during the search. After screening articles based on inclusion criteria, 44 studies remained. In clinical trials, probiotic consumption affects bone health parameters such as serum calcium levels (3.82; 95% CI: 1.05, 6.59 mmol/l), urinary calcium levels (4.85; 95% CI: 1.16, 8.53 mmol/l), and parathyroid hormone (PTH) levels (-5.53; 95% CI: -9.83, -0.86 ng/l). In most studies, Lactobacillus species such as L. helveticus, L. reuteri, and L. casei were consumed and women aged 50 years or older were assessed. Spinal and total hip bone mineral density (BMD) was not affected significantly by probiotic consumption. In 37 animal experiments, probiotic or symbiotic feeding mostly had effects on bone health parameters. Some strains of Bifidobacterium and Lactobacillus including L. reuteri, L. casei, L. paracasei, L. bulgaricus, and L. acidophilus have indicated beneficial effects on bone health parameters. In conclusion, this systematic review and meta-analysis indicate that probiotic supplementation might improve bone health. Further studies are needed to decide on the best probiotic species and appropriate dosages.

The effects of dietary selenium supplementation on inflammatory markers among patients with metabolic diseases: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: Selenium (Se) is a trace element having significant effects on human metabolism. Recent studies suggest that Se supplementation have a pivotal effect on the inflammatory markers. Therefore, the aim of this study was to assess the effect of Se supplementation on plasma inflammatory markers including C-reactive protein (CRP) and high-sensitivity C-reactive protein (hs-CRP) and nitric oxide (NO) as a stress oxidative index, among patients with metabolic diseases. METHODS: To assess the effects of Se on the inflammatory markers, following the PRISMA-P guidelines, we systematically searched ISI/WOS, PubMed/MEDLINE, and Scopus for studies that assessed the effect of Se supplementation on the inflammatory markers. Data extraction was performed by two independent investigators. Using the random effects or fixed-effects model depending on the results of heterogeneity tests was used to estimate the pooled standardized mean difference (SMD). Heterogeneity between studies was assessed using Cochran's Q test and I2 index. RESULTS: The initial search revealed 3,320 papers. After screening process and considering inclusion criteria, 7 publications were eligible for inclusion in the meta-analysis. The meta-analysis results showed that Se supplementation did not significantly affect CRP and hs-CRP concentrations (mean difference (MD) = -0.15; 95% CI: -0.55- 0.23; P = 0.43). Subgroup analysis of CRP type showed that Se supplementation significantly decreased hs-CRP level (pooled SMD = -0.44; 95% CI: -0.67-0.21). Moreover, no significant change was observed in NO level by continuing to take Se supplementation, (pooled SMD: 0.003, 95%CI: -0.26, 0.26). CONCLUSIONS: This study revealed that Se supplementation would have desirable effects on cardio-metabolic indicators through affecting the levels of inflammatory markers. Given the importance of concerns, more attention should be given to more prospective studies with longer follow-up.

Legume and Nuts Consumption in Relation to Glioma: A Case- Control Study.

Data on the link between legume and nuts consumption and risk of glioma are controversial. The current study aimed to investigate the relation between legume and nuts consumption and glioma in a case-control study in Iranian adults. In this hospital-based case-control study, we enrolled 128 pathologically confirmed new cases of glioma and 256 age and sex-matched controls. Dietary intakes of study participants were assessed using the validated Block-format 123-item semi-quantitative FFQ. Data on potential confounders were also collected through the use of a pre-tested questionnaire. Mean age of cases and controls were 43.4 and 42.8 years, respectively. Individuals with the greatest legume and nuts consumption were less likely to have glioma compared with those with the lowest consumption (0.52; 95% CI: 0.30-0.88). This inverse association was not changed after controlling for age, sex and energy intake (0.46; 95% CI: 0.26-0.81). The association remained statistically significant even after taking other potential confounders, including dietary intakes into account (0.32; 95% CI: 0.14-0.72). Additional adjustments for BMI did not alter the association; such that individuals in the top category of legume and nuts consumption were 66% less likely to have glioma compared with those in the bottom category (0.34; 95% CI: 0.15-0.76). We found an inverse association between legume and nuts consumption and odds of glioma, even after controlling for a wide range of confounders.

Index of Nutritional Quality (INQ) and the Risk of Obesity in Male Adolescents: a Case-Control Study.

Dietary factors may play a key role in the etiology of obesity. The Index of Nutritional Quality (INQ) provides a comprehensive overview of the nutrients content of the diet. This study aimed to investigate the association between INQ and obesity in male adolescents. We hypothesize that receiving a high-quality diet reduces the risk of overweight or obese. This study was carried out on 214 obese/overweight as the case group and 321 normal-weight male adolescents as the control group. Dietary intakes of the participants were collected using a food frequency questionnaire (FFQ). The FFQ-derived dietary data were used to calculate the INQ scores. After adjustments for age and height, an inverse association was found between obesity and INQ of iron, vitamin B6, and magnesium, and a positive association was found between obesity and INQ of zinc (all P < 0.05). After further adjustments for nutritional knowledge and calorie intake, an inverse association was observed between obesity and INQ of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium (all P < 0.05). The positive association of obesity and INQ of zinc remained significant after adjustments. A higher intake of vitamin C, iron, vitamin B6, pantothenic acid, selenium, and magnesium and a lower intake of zinc may be protective against adolescent obesity. More longitudinal studies are required to investigate the relationship between these nutrients and obesity.

Consumption of milk and dairy products and risk of osteoporosis and hip fracture: a systematic review and Meta-analysis.

Background: Although some studies have reported the beneficial effects of milk and dairy product consumption on osteoporosis and risk of fracture, the findings are conflicting.Purpose: We summarized earlier data on the association between milk and dairy intake and risk of osteoporosis and hip fracture through a meta-analysis.Methods: A systematic literature search of relevant reports published in PubMed, ISI (Web of Science), EMBASE, SCOPUS, and Google Scholar until August 2018 was conducted.Results: Total dairy intake was protectively associated with reduced risk of osteoporosis based on cross-sectional and case-control studies (0.63; 95% CI: 0.55-0.73). Milk consumption was not associated with the risk of osteoporosis (overall RR = 0.79; 95% CI: 0.57-1.08). In non-linear dose-response meta-analysis, increase intake of dairy (at the level of 0 to 250 grams per day) was associated with a reduced risk of osteoporosis (Pnonlinearty = 0.005). Meta-regression of included studies revealed an inverse linear association between dairy and milk intake and risk of osteoporosis; such that every additional 200-gram intake of dairy and milk was associated with a 22% and 37% reduced risk of osteoporosis, respectively. In terms of hip fracture, milk consumption was associated with a 25% reduced risk of hip fracture only in cross-sectional and case-control studies (overall RR = 0.75; 95%CI: 0.57-0.99). In linear meta-regression, every additional 200-gram milk intake per day was associated with a 9% greater risk of hip fracture in cohort studies.Conclusion: Despite an inverse association between milk and dairy intake and risk of osteoporosis and hip fracture in cross-sectional and case-control studies, no such association was seen in cohort studies. Given the advantages of the cohort over case-control studies, we concluded that a greater intake of milk and dairy products was not associated with a lower risk of osteoporosis and hip fracture.

Metabolically healthy status and BMI in relation to depression: A systematic review of observational studies.

AIM: Findings of association between metabolically healthy status and BMI and risk of depression are controversial. This study aimed to assess the relation between metabolically healthy status and BMI and depression. METHODS: All published studies up to 25 June 2018 were searched by using the databases of PubMed, ISI Web of Science, SCOPUS and Google Scholar and following key words were used: metabolically AND (healthy OR unhealthy OR benign) AND (overweight OR obes* OR "over weight") AND phenotype AND (depression OR depress* OR "depressive disorder"). RESULTS: After screening title and abstract and considering inclusion criteria, 5 studies were found to be included in our study. Metabolically unhealthy obesity was associated with 30%-83% increased risk of depression and metabolically unhealthy non-obesity was associated with 19%-60% increased risk of depression. Metabolically healthy obesity was not associated with the risk of depression in all studies. CONCLUSIONS: In conclusion, metabolically health status and BMI are associated with risk of depression. Metabolically unhealthy situation increased risk of depression greater than metabolically healthy status.

Tea and coffee consumption in relation to glioma: a case-control study.

PURPOSE: Data on the link between tea and coffee consumption and risk of glioma are controversial. We aimed to examine the association between tea and coffee consumption and glioma in Iranian adults. METHODS: In this hospital-based case-control study, we enrolled 128 pathologically confirmed new cases of glioma and 256 age- and sex-matched controls. Dietary intakes of study participants including tea and coffee consumption was assessed using the validated Block-format 123-item semi-quantitative FFQ. Participants were categorized based on tertiles of tea and coffee consumption. Data on potential confounders were also collected through the use of pre-tested questionnaire. RESULTS: Individuals with the greatest tea consumption were less likely to have glioma compared with those with the lowest consumption (0.36; 0.20-0.68). This inverse association was not changed after controlling for energy intake. The association remained statistically significant even after taking other potential confounders, including dietary intakes of red and processed meats, legumes and nuts, fruits, salt and mutual effects of tea and coffee consumption, into account (0.33; 0.13-0.86). Additional adjustments for BMI did not alter the association. After controlling for potential confounders, including dietary intakes and BMI, coffee consumption was inversely associated with odds of glioma; such that individuals in the top category of coffee consumption were 91% less likely to have glioma compared with those in the bottom category (0.09; 0.03-0.24). Considering coffee and tea intake combined, those in the highest tertile were 65% less likely to have glioma compared with those in the lowest tertile (0.35; 0.15-0.83). CONCLUSION: We found an inverse association between tea and coffee consumption and odds of glioma, even after controlling for a wide range of confounders.

Patterns of nutrients intakes in relation to glioma: A case-control study.

BACKGROUND & AIMS: Nutrient pattern analysis is an easy way to compare nutrient intakes across different nations due to the universality of nutrients nature. The current study aimed to investigate the relation between patterns of nutrients intake and glioma in a case-control study in Iranian adults. METHODS: In this hospital-based case-control study, we enrolled 128 pathologically confirmed new cases of glioma and 256 age and sex-matched controls. Dietary intakes of study participants were assessed using the validated Block-format 123-item semi-quantitative FFQ. Data on potential confounders were also collected through the use of pre-tested questionnaire. RESULTS: Four nutrient patterns were identified through the use of factor analysis. Participants were categorized based on tertiles of nutrient patterns' scores. Adherence to the first nutrient pattern was not significantly associated with the odds of glioma (0.93; 0.40-2.15). Participants with greater adherence to the second nutrient pattern were less likely to have glioma in crude model (0.48; 0.28-0.83). The inverse association remained significant after controlling for age, sex and energy intake (0.42; 0.24-0.78). Further controlling for other potential confounders, including BMI, resulted in the disappearance of the association (0.52; 0.25-1.10). Greater adherence to the third nutrient pattern was directly associated with the odds of glioma (1.92; 1.10-3.35). Even after controlling for sex, age and energy intake, the association was statistically significant (2.83; 1.28-4.21). However, when other confounders were taken into account, the association became non-significant (2.28; 0.89-5.82). The fourth nutrient pattern was not associated with the odds of glioma (0.71; 0.35-1.42). CONCLUSION: We failed to find any significant independent association between nutrient patterns and odds of glioma. Further studies needed to confirm these findings.

Letter to editor: careful literature search and exact data extraction are milestones of a meta-analysis: the case of dairy consumption and hip fracture.

In a recent issue of the BMC Public Health journal, Bian et al. described the results of an interesting meta-analysis on the association between dairy products consumption and risk of hip fracture. Although the results are important and valuable, some critical points should be noticed in the explanation of these findings. We prepared these critical points in a letter to the editor and hope to be an interest of you.

Fruit and vegetable consumption and risk of depression: accumulative evidence from an updated systematic review and meta-analysis of epidemiological studies.

Findings from observational studies investigating the association between fruit and vegetable consumption and risk of depression were inconsistent. We conducted a systematic review and meta-analysis to summarise available data on the association between fruit and vegetable intake and depression. A systematic literature search of relevant reports published in Medline/PubMed, ISI (Web of Science), SCOPUS and Google Scholar until Oct 2017 was conducted. Data from 27 publications (sixteen cross-sectional, nine cohort and two case-control studies) on fruit, vegetables and/or total fruit and vegetable consumption in relation to depression were included in the systematic review. A total of eighteen studies that reported relative risks (RR), hazard ratios or OR for the relationship were included in the meta-analysis. The pooled RR for depression in the highest v. the lowest category of fruit intake was 0·83 (95 % CI 0·71, 0·98) in cohort studies and 0·76 (95 % CI 0·63, 0·92) in cross-sectional studies. Consumption of vegetables was also associated with a 14 % lower risk of depression (overall RR=0·86; 95 % CI 0·75, 0·98) in cohort studies and a 25 % lower risk of depression (overall RR=0·75; 95 % CI 0·62, 0·91) in cross-sectional studies. Moreover, an inverse significant association was observed between intake of total fruit and vegetables and risk of depression (overall RR=0·80; 95 % CI 0·65, 0·98) in cross-sectional studies. In a non-linear dose-response association, we failed to find any significant association between fruit or vegetable intake and risk of depression (fruit (cross-sectional studies): P non-linearty=0·12; vegetables (cross-sectional studies): P non-linearty<0·001; (cohort studies) P non-linearty=0·97). Meta-regression of included observational studies revealed an inverse linear association between fruit or vegetable intake and risk of depression, such that every 100-g increased intake of fruit was associated with a 3 % reduced risk of depression in cohort studies (RR=0·97; 95 % CI 0·95, 0·99). With regard to vegetable consumption, every 100-g increase in intake was associated with a 3 % reduced risk of depression in cohort studies (RR=0·97; 95 % CI 0·95, 0·98) and 5 % reduced odds in cross-sectional studies (RR=0·95; 95 % CI 0·91, 0·98). This meta-analysis of observational studies provides further evidence that fruit and vegetable intake was protectively associated with depression. This finding supports the current recommendation of increasing fruit and vegetable intake to improve mental health.

Vitamin C intake in relation to bone mineral density and risk of hip fracture and osteoporosis: a systematic review and meta-analysis of observational studies.

We aimed to systematically review available data on the association between vitamin C intake and bone mineral density (BMD), as well as risk of fractures and osteoporosis, and to summarise this information through a meta-analysis. Previous studies on vitamin C intake in relation to BMD and risk of fracture and osteoporosis were selected through searching PubMed, Scopus, ISI Web of Science and Google Scholar databases before February 2017, using MeSH and text words. To pool data, either a fixed-effects model or a random-effects model was used, and for assessing heterogeneity, Cochran's Q and I 2 tests were used. Subgroup analysis was applied to define possible sources of heterogeneity. Greater dietary vitamin C intake was positively associated with BMD at femoral neck (pooled r 0·18; 0·06, 0·30) and lumbar spine (pooled r 0·14; 95 % CI 0·06, 0·22); however, significant between-study heterogeneity was found at femoral neck: I 2=87·6 %, P heterogeneity<0·001. In addition, we found a non-significant association between dietary vitamin C intake and the risk of hip fracture (overall relative risk=0·74; 95 % CI 0·51, 1·08). Significant between-study heterogeneity was found (I 2=79·1 %, P heterogeneity<0·001), and subgroup analysis indicated that study design, sex and age were the main sources of heterogeneity. Greater dietary vitamin C intake was associated with a 33 % lower risk of osteoporosis (overall relative risk=0·67; 95 % CI 0·47, 0·94). Greater dietary vitamin C intake was associated with a lower risk of hip fracture and osteoporosis, as well as higher BMD, at femoral neck and lumbar spine.