The effect of selenium supplementation on oxidative stress, clinical symptoms and mental health status in patients with migraine: a study protocol for a double-blinded randomized clinical trial.

BACKGROUND: Despite a number of recommended strategies, effective treatment of migraine remains elusive. Given the role of oxidative stress in the pathogenesis of migraine, selenium, as an antioxidant nutrient, may have a beneficial effect on migraine outcomes. However, no study has explored the effects of selenium supplementation on migraine symptoms, oxidative stress biomarkers, and mental health. Therefore, this randomized, double-blinded, placebo-controlled clinical trial aims to examine the effects of selenium supplementation among migraine patients. METHODS: Seventy-two migraine patients will receive either 200 µg/day selenium supplement (n = 36) or placebo (n = 36) for 12 weeks in a randomized, double-blinded, placebo-controlled study. The severity, frequency, and duration of headaches, mental health indices including depression, anxiety, and distress, and quality of life, as well as biomarkers of oxidative stress such as nitric oxide (NO), malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidant status (TOS), will be measured at the baseline and end of the study. The intention-to-treat (ITT) approach will be used to estimate missing values. One-way analysis of covariance (ANCOVA) will be performed to detect the effect of selenium supplementation on outcome variables. DISCUSSION: Oxidative stress is recognized as a key contributor to migraine pathogenesis. Selenium is an essential trace element with antioxidant properties, capable of crossing the blood-brain barrier (BBB), holding promise to alleviate the oxidative stress and neurotoxicity. Thus, selenium may beneficially affect clinical symptoms and oxidative stress as well as the quality of life in migraine patients. TRIAL REGISTRATION: This trial was registered in the Iranian Registry of Clinical Trials ( https://www.irct.ir/ ) on 27 May 2023 with the code number IRCT20121216011763N60.

Dietary Magnesium Intake Is Inversely Associated With Ulcerative Colitis: A Case-Control Study.

Background: Ulcerative colitis (UC) causes long-lasting inflammation and ulcers in the gut. Limited observational data are available linking dietary magnesium intake and UC. In the present study, we aimed to investigate the association between dietary magnesium intake and UC in adults. Methods: The current population-based case-control study was performed on 109 UC patients and 218 age (±2 years) and sex-matched controls. The diagnosis of UC was made according to the standard criteria by a gastroenterology specialist. Dietary intakes were assessed using a validated self-administrated 106-item dish-based Food Frequency Questionnaire (FFQ). We also used a pretested questionnaire to collect data on potential confounders. Results: Individuals in the top tertile of magnesium intake were less likely to have UC compared with those in the bottom tertile. A significant inverse relationship was found between dietary magnesium intake and UC (odds ratio [OR]: 0.32, 95% confidence interval [CI]: 0.18-0.59) in the crude model. This relationship was also observed when we took several potential confounding into account (OR: 0.30, 95% CI: 0.14-0.68). Conclusions: Adherence to a magnesium-rich diet may have a role in preventing UC. However, further studies are needed to confirm our findings.

Associations of major dietary patterns with cardiometabolic risk factors among Iranian patients with type 1 diabetes.

Objective: To examine the associations between dietary patterns and cardiometabolic risk factors among type 1 diabetic (T1D) patients. Methods: This cross-sectional study was conducted on 229 Iranian T1D patients. Data on dietary intakes were collected using a 168-item food frequency questionnaire. To identify major dietary patterns, we merged data on the 168 food items to obtain 23 food groups. Then, we constructed major dietary patterns using factor analysis with varimax rotation. We used binary logistic regression to assess the association between dietary patterns and cardiometabolic risk factors, in which potential confounders were adjusted. Results: Four dietary patterns were identified: Western, unhealthy, traditional, and semi-healthy patterns. After adjusting for confounders including demographic variables, physical activity, energy intake, and medical history, participants in the highest tertile of the Western dietary pattern had 2.53 (95 % CI: 1.03-6.22) and 3.37 (95 % CI: 1.18-9.63) times more odds of elevated HbA1c and low estimated glucose disposal rate (eGDR), respectively, compared with those in the lowest tertile. Such the positive association was also seen for elevated fasting blood glucose (FBG). Moreover, individuals in the top tertile of unhealthy diet had more odds of elevated LDL-c and abdominal obesity than those in the lowest tertile. Regarding the semi-healthy diet, higher adherence was associated with 51 % lower odds of elevated FBG (OR: 0.49, 95 % CI: 0.24-0.99). For other outcomes, no significant association was found. Conclusion: We found that T1D patients may take benefit from adherence to a semi-healthy diet with a low amount of unhealthy and Western-related foods.

Is oral consumption of dates (Phoenix dactylifera L. fruit) in the peripartum period effective and safe integrative care to facilitate childbirth and improve perinatal outcomes: a comprehensive revised systematic review and dose-response meta-analysis.

BACKGROUND: Recent reviews have reported inconclusive results regarding the usefulness of consuming dates (Phoenix dactylifera L. fruit) in the peripartum period. Hence, this updated systematic review with meta-analysis sought to investigate the efficacy and safety of this integrated intervention in facilitating childbirth and improving perinatal outcomes. METHODS: Eight data sources were searched comprehensively from their inception until April 30, 2023. Parallel-group randomized and non-randomized controlled trials published in any language were included if conducted during peripartum (i.e., third trimester of pregnancy, late pregnancy, labor, or postpartum) to assess standard care plus oral consumption of dates versus standard care alone or combined with other alternative interventions. The Cochrane Collaboration's Risk of Bias (RoB) assessment tools and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) were employed to evaluate the potential RoB and the overall quality of the evidence, respectively. Sufficient data were pooled by a random-effect approach utilizing Stata software. RESULTS: Of 2,460 records in the initial search, 48 studies reported in 55 publications were included. Data were insufficient for meta-analysis regarding fetal, neonatal, or infant outcomes; nonetheless, most outcomes were not substantially different between dates consumer and standard care groups. However, meta-analyses revealed that dates consumption in late pregnancy significantly shortened the length of gestation and labor, except for the second labor stage; declined the need for labor induction; accelerated spontaneity of delivery; raised cervical dilatation (CD) upon admission, Bishop score, and frequency of spontaneous vaginal delivery. The dates intake in labor also significantly reduced labor duration, except for the third labor stage, and increased CD two hours post-intervention. Moreover, the intervention during postpartum significantly boosted the breast milk quantity and reduced post-delivery hemorrhage. Likewise, dates supplementation in the third trimester of pregnancy significantly increased maternal hemoglobin levels. The overall evidence quality was also unacceptable, and RoB was high in most studies. Furthermore, the intervention's safety was recorded only in four trials. CONCLUSION: More well-designed investigations are required to robustly support consuming dates during peripartum as effective and safe integrated care. TRIAL REGISTRATION: PROSPERO Registration No: CRD42023399626.

The relation of dietary protein intake before and during the pregnancy with gestational diabetes mellitus (GDM): A GRADE-assessed systematic review and dose-response meta-analysis of epidemiologic studies.

BACKGROUND: Although previous studies investigated the relation of protein intake and gestational diabetes mellitus (GDM), their findings were controversial. Therefore, we aimed to summarize this association, through a comprehensive systematic review and dose-response meta-analysis. METHODS: Electronic databases including MEDLINE (PubMed), ISI Web of Science, Scopus and motor engineering of Google Scholar were systematically searched up to April 2023. Observational studies which investigated odds of GDM in relation to protein intake were included. RESULTS: A total of 31,005 participants with 3451 cases of GDM from 13 eligible investigations were included in the systematic review and meta-analysis. Comparing the highest and lowest intakes of total, animal, and plant proteins revealed the summary RRs of 1.82 (95% CI: 1.42, 2.33), 1.79 (95% CI: 1.50, 2.14), and 0.98 (95% CI: 0.81, 1.20), respectively, indicating a significant positive association between total and animal protein intake and GDM. In the dose-response analyses, each 5% increment in energy intake from total protein during pregnancy was related to 20% increased odds of GDM (RR = 1.20; 95% CI: 1.09, 1.33). In the non-linear dose-response analyses, we found a non-linear association for animal protein intake during pregnancy (P for non-linearity <0.001); so that, a risk increase was seen from zero to 10% of energy intake from animal proteins, however, a risk reduction was seen after 10% of energy intake. However, there was not any significant non-linear trend between plant protein intake during pregnancy and risk of GDM. Based on the GRADE assessment, the quality of evidence for total, animal and plant protein was rated as "moderate", "moderate" and "very low", respectively. CONCLUSION: We found a significant positive association between total protein intake and GDM; however, the associations of animal and plant protein intake with GDM were dose-dependent.

Association between nutritional status and biochemical markers among hematopoietic stem cell transplant candidates: a cross-sectional study.

AIM: Candidates of Hematopoietic Stem Cell Transplantation (HSCT) may be at nutritional risk due to decreased oral intake, high nutritional requirements and nutrient malabsorption. The aim of this study was to evaluate the association between nutritional status and blood biomarkers in candidates of HSCT. METHODS: A total of 278 patients aged 18-65 years old were recruited and their baseline demographic and clinical characteristics were recorded. All subjects underwent nutritional status analysis using Nutritional Risk Screening (NRS-2002). Blood biomarkers including C-reactive protein (CRP), Erythrocyte Sedimentation Rate (ESR), hemoglobin, albumin and total protein as well as CRP-albumin ratio (CAR) and Body Mass Index (BMI) were measured and compared between two groups based on Nutritional Risk Screening (NRS-2002) within 24 h of admission in Bone Marrow Transplant ward. RESULTS: The results showed that undernourished patients (NRS ≥ 3) had significantly higher inflammatory markers including ESR, CRP and CAR as well as lower BMI and serum albumin and hemoglobin concentrations (P < 0.05); however, no significant association was observed in terms of total protein even after adjusting for confounders (P > 0.05). CONCLUSIONS: This study revealed that BMI combined with biochemical markers are the appropriate parameters for assessment of nutritional status in HSCT candidates. Furthermore, the nutritional status was verified to be significantly associated with systematic inflammation.

Dietary inflammatory index in relation to severe coronary artery disease in Iranian adults.

Background: Limited findings are available on the relationship between dietary inflammation index (DII) and severe coronary artery disease (CAD). Considering the high prevalence of CAD and its complications, we examined the relationship between DII and CAD. Methods: This cross-sectional study was conducted on 275 adults who underwent elective angiography. Severe coronary artery disease was measured by the gensini scoring system. DII was measured by a valid semi-quantitative 168-item food frequency questionnaire (FFQ). Blood samples were collected after 12 h of fasting to measure serum lipid profile and quantitative C-reactive protein (q-CRP) levels. Binary logistic regression was used to calculate the odds (OR) and 95% confidence interval (CI). Results: People in the last tertile of the DII had a higher chance of suffering from severe coronary artery disease (OR: 3.71; 95% CI: 1.97-6.98), hypercholesterolemia (OR: 2.73; 95% CI: 5.03-1.48), reduced HDL-cholesterol levels (OR: 3.77; 95% CI: 9.34-1.52), and hypertension (OR: 1.93; 95% CI: 3.49-1.06) compared to people in the first tertile. After adjusting for confounding factors, the relationship remained significant. A direct and significant relationship was observed between the DII and increased q-CRP levels, which disappeared after adjusting for confounding factors in the adjusted model (OR: 2.02; 95% CI: 0.86-4.73). Conclusion: This cross-sectional study showed a direct and linear relationship between following an anti-inflammatory diet and decreasing the chance of severe CAD. Therefore, it seems necessary to implement community-based educational programs to promote healthy nutrition in order to prevent CADs.

Dietary linoleic acid intake in relation to breast cancer: A case-control study.

Background: The present study aimed to investigate the association between dietary linoleic acid (LA) intake and breast cancer in women. Methods: In this population-based case-control study, we enrolled 350 pathologically confirmed breast cancer cases and 700 controls which were matched with cases in terms of age and socioeconomic status. Dietary intakes were assessed using a 106-item Willett-format semi-quantitative dish-based food frequency questionnaire (DS-FFQ). Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were estimated. Results: A significant inverse association was found between LA intake and odds of breast cancer (OR: 0.41, 95% CI: 0.30-0.56). After adjusting for potential confounders, women in the highest tertile of dietary LA intake were 48% less likely to have breast cancer compared with those in the lowest tertile (OR: 0.52, 95% CI: 0.28-0.95). Such a significant inverse association was also seen among normal-weight women (OR: 0.29, 95% CI: 0.14-0.63), and premenopausal women (OR: 0.15, 95% CI: 0.02-0.95). Conclusion: The findings of current study provide evidence for a protective role of LA against breast cancer particularly among normal-weight and premenopausal women. Prospective studies are needed to confirm this association.

Effects of marine-derived n-3 PUFA supplementation on soluble adhesion molecules: A systematic review and dose-response meta-analysis of randomized controlled trials.

Long-chain n-3 poly unsaturated fatty acids have anti-inflammatory effects but their effects on serum levels of adhesion molecules are inconsistent and contradictory. In this updated systematic review and meta-analysis, marine sources of omega-3 fatty acids were pooled up to determine the effects of omega-3 supplementation on adhesion molecules. PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases (from inception to April 2023) were searched and all RCTs investigating the effects of marine sources of omega-3, on blood concentrations of adhesion molecules were included and a meta-analysis undertaken. Forty-two RCTs were included involving 3555 participants aged from 18 to 75 years. Meta-analysis of 38 arms from 30 RCTs reporting serum concentrations of vascular cell adhesion molecule-1 (VCAM-1) showed a significant reduction after omega-3 supplementation (WMD: -1.26, 95% CI: -1.88 to -0.64 ng/mL, P < 0.001). Meta-analysis of 40 arms from 30 RCTs reporting serum concentrations of intercellular adhesion molecule-1 (ICAM-1) revealed a reduction following omega-3 supplementation, although it was not significant (WMD: -1.76, 95%CI: -3.68 to 0.16 ng/mL, P = 0.07). Meta-analysis of 27 arms from 21 trials showed no effect on E-selectin (WMD: 0.01, 95%CI: -0.02 to 0.04 ng/mL, P = 0.62). Pooling 15 arms from 11 RCTs showed a marginally significant reducing effect on P-selectin concentrations (WMD: -2.67, 95%CI: -5.53 to 0.19 ng/mL, P = 0.06). A considerable decrease in VCAM concentration was observed after omega-3 supplementation in this meta-analysis with a trend to decreases in both ICAM and P-selectin levels, with effects that may be significant depending on study design, and there was no effect on E-selectin.

Fish consumption and risk of prostate cancer or its mortality: an updated systematic review and dose-response meta-analysis of prospective cohort studies.

Since the release of the last meta-analysis on the association between fish intake and prostate cancer risk, several cohort studies have been published. Moreover, none of the previous meta-analyzes examined the dose-response association between fish intake and prostate cancer. Therefore, the current dose-response meta-analysis was conducted to summarize available findings on the associations of fish intake with the risk of prostate cancer in men. Online databases of PubMed, Scopus, and Web of Science were systematically searched up to September 2022. We included prospective cohort studies that examined the associations of fish intake with the risk of prostate cancer (total, localized, and advanced prostate cancer), its mortality, and cancer progression. Summary relative risks (RR) and 95% confidence intervals (CI) were calculated for the highest versus lowest categories of fish intake using random-effects models. Also, linear and non-linear dose-response analyzes were conducted. In total, 25 prospective cohort studies, recruiting 1,216,474 men, were included in the systematic review, and 22 studies were included in the meta-analysis. During the follow-up periods, ranging from 6 to 33 years, a total of 44,722 cases of prostate cancer were recorded. The comparison between the highest and lowest intakes of total fish revealed the summary RRs of 0.97 (95% CI: 0.86-1.10) for total, 1.01 (95% CI: 0.91-1.13) for advanced, and 0.90 (95% CI: 0.72-1.12) for localized prostate cancer, indicating no significant association. Moreover, the summary RR was 0.55 (95% CI: 0.33-0.92) for prostate cancer mortality and 0.84 (95% CI: 0.65-1.10) for prostate cancer progression, indicating an inverse association between fish intake and prostate cancer mortality. Also, in the dose-response analyzes, each 20 gram/day increase in total fish intake was associated with a 12% lower risk of prostate cancer mortality. Our findings support the protective association between total fish intake and the risk of prostate cancer mortality.

A case-control study on the association between adherence to a Mediterranean-style diet and breast cancer.

Background: Previous studies on the association between diet and breast cancer are mostly from Western populations, and data from Middle East countries are scarce, where the prevalence of breast cancer is high; therefore, it ranks first among other cancers. This population-based case-control study aimed to investigate the relationship between a Mediterranean-style diet and breast cancer among Iranian women. Methods: In the current study, 350 new cases of breast cancer and 700 age- and socioeconomic status-matched controls were enrolled. We evaluated the dietary intakes of participants by using a 106-item Willett-format semi-quantitative dish-based food frequency questionnaire (SQ-FFQ). We calculated the Mediterranean diet score according to the dietary intakes of participants. In addition, using pre-tested questionnaires, we collected information on potential confounding variables. Results: In this study, we found a significant inverse association between the Mediterranean diet and breast cancer so that after controlling for potential confounders, individuals in the highest tertile of the Mediterranean diet score compared with those in the lowest tertile were 57% less likely to have breast cancer [odds ratio (OR): 0.43, 95% confidence interval (CI): 0.28-0.67]. Such an inverse association was also observed for postmenopausal women. Similarly, after controlling for potential confounding variables, high adherence to the Mediterranean dietary pattern was associated with lower odds of breast cancer (OR: 0.37, 95% CI: 0.23-0.60). However, this relationship was not significant among premenopausal women. Conclusion: We found that adherence to Mediterranean dietary pattern was associated with reduced odds of breast cancer. Studies with prospective design are needed to further examine this association.

Association of major dietary patterns with advanced glycation end products and high-sensitivity C-reactive protein in people with type 1 diabetes mellitus.

BACKGROUND: The associations of diet with serum levels of advanced glycation end products (AGEs) and high-sensitivity C-reactive protein (hs-CRP) have been examined in patients with type 2 diabetes mellitus (T2DM). However, data on patients with type 1 diabetes mellitus (T1DM) are limited. Therefore, this study was conducted to investigate the associations of major dietary patterns with serum levels of AGEs and hs-CRP among patients with T1DM. METHODS: A total of 229 patients with T1DM participated in this current cross-sectional study. We collected dietary data using a validated food frequency questionnaire (FFQ). The factor analysis approach was used to determine major dietary patterns. A fasting blood sample was collected from each participant to assess serum levels of AGEs and hs-CRP. The associations of dietary patterns with elevated levels of AGEs and hs-CRP were assessed using binary logistic regression. RESULTS: Patients with T1DM in the highest tertile of a Western dietary pattern had 4.32 times higher odds of having elevated AGEs than those in the lowest tertile (OR: 4.32, 95% CI: 1.86-10.05). Additionally, adherence to the Western diet was associated with 2.97 times greater odds of having elevated hs-CRP (> 3 mg/L) (OR: 2.97, 95% CI: 1.22-7.24) in these patients. Such positive associations were not observed for unhealthy and traditional dietary patterns. Moreover, higher adherence to a semi-healthy diet (characterized by high consumption of white meat, whole grains, processed meat, and a low salt intake) was associated with 87% lower odds of having elevated hs-CRP (OR: 0.13, 95% CI: 0.05-0.35). However, we found no significant association between the semi-healthy diet and AGEs levels. CONCLUSION: We found that adherence to a Western dietary pattern was associated with elevated levels of AGEs/hs-CRP in patients with T1DM. Also, we discovered a significant inverse association between adherence to a semi-healthy diet and hs-CRP levels.

Adjuvant pomegranate juice intake improves the inflammatory status of hospitalized COVID-19 patients: A randomized and placebo-controlled trial.

BACKGROUND: This study aimed to evaluate the effect of pomegranate juice intake on the inflammatory status and complete blood count in hospitalized Covid-19 patients. METHODS: This randomized, double-blinded placebo-controlled trial included 48 patients with two parallel arms. In addition to the standard care provided at the hospital, the patients consumed 500 mL of whole pomegranate juice (PJ) daily or a placebo for 14 days. Inflammatory markers (C-reactive protein (CRP), interleukin-6 (IL-6), erythrocyte sedimentation rate (ESR)) and complete blood count were determined at baseline and after the 14 days of intervention. RESULTS: At the end of the intervention, a significant decreased was observed in primary outcomes [mean difference (95 %CI)] including IL-6 [5.24(0.87-9.61)], CRP [23.19(11.93-34.44)] and ESR [10.52(1.54-19.50)] in the PJ group vs. before the intervention. In addition, significant changes were also observed in the some of the secondary outcomes, including neutrophils, lymphocytes, platelets, platelets-to-lymphocyte(PLR) and neutrophils-to-lymphocyte (NLR) ratios (p < 0.05) in the PJ group compared to before the intervention. At the end of the intervention period, the mean change of IL-6 [- 7.09(-12.21 to - 1.96)], white blood cells [- 3.09(- 6.14 to - 0.05)], neutrophils [- 9.12(-18.08 to -0.15)], lymphocyte [7.05(0.17-13.92)], platelets [- 94.54(- 139.33 to - 49.75)], PLR [- 15.99(- 29.31 to - 2.67)], blood oxygen saturation [1.75(0.13-3.37)] and MCV [0.31(- 0.25 to 0.88)] levels were significantly different between groups while no difference was observed between the two groups in other blood indices. CONCLUSION: Our results suggest that pomegranate juice intake might slightly improve the inflammatory status and CBC outcomes of COVID-19 patients and it may be beneficial.

Association between nut consumption and prostate cancer risk in adults: A systematic review and dose-response meta-analysis of observational studies.

AIMS: Data on the association between nut consumption and prostate cancer risk are conflicting. Therefore, this systematic review and dose-response meta-analysis aimed to summarize available findings from observational studies on the associations of nut intake with risk of total, advanced, non-advanced, and fatal prostate cancers. DATA SYNTHESIS: We searched the online databases of PubMed, Scopus, and Web of Science as well as Google Scholar using appropriate keywords to identify eligible articles up to September 2022. In total, 11 articles with a total sample size of 287,786 participants and 32,213 cases of prostate cancer were included in the current systematic review and meta-analysis. By comparing the highest and lowest intake of total nuts, pooled relative risks (RRs) and 95% confidence intervals (95% CIs) for total, advanced, non-advanced, and fatal prostate cancers were 0.94 (95% CI: 0.85-1.04, P = 0.22), 1.10 (95% CI: 0.98-1.24, P = 0.12), 0.97 (95% CI: 0.85-1.11, P = 0.69), 0.97 (95% CI: 0.79-1.18, P = 0.73), respectively, which indicated non-significant inverse associations for total, non-advanced, and fatal prostate cancers and a non-significant positive association for advanced prostate cancer. In the dose-response analyses, we found no evidence of a linear or non-linear association between total nut intake and prostate cancer risk. Data on other types of nuts, including walnut, tree nuts, peanut, and peanut butter, were not sufficient for performing a meta-analysis. CONCLUSION: We found no significant association between nut intake and risk of total, advanced, non-advanced, and fatal prostate cancer. Further studies are required to confirm our findings. PROSPERO REGISTRATION CODE: CRD42022347094. ETHICAL APPROVAL: Not required.

Dietary intake and biomarkers of linoleic acid and risk of prostate cancer in men: A systematic review and dose-response meta-analysis of prospective cohort studies.

Findings on the association of dietary intake and tissue biomarkers of linoleic acid (LA) with the risk of prostate cancer are conflicting. Also, no meta-analysis summarized available findings in this regard. Therefore, the current systematic review and dose-response meta-analysis were done to summarize the findings of prospective cohort studies that assessed dietary intake and tissue biomarkers of LA in relation to prostate cancer risk in adults. We conducted a systematic search using online databases, including PubMed, Scopus, and ISI Web of Science, to identify eligible articles published up to January 2023. We included prospective cohort studies that examined the associations of dietary intake and tissue biomarkers of LA with the risk of prostate cancer (total, advanced, and fatal prostate cancer). Summary relative risks (RR) and 95% confidence intervals (CI) were calculated for the highest versus lowest intakes/tissue levels of LA using a fixed-effects model. Also, linear and non-linear dose-response analyses were conducted. In total, 15 prospective cohort studies were included. These studies recruited a total sample size of 511,622 participants with an age range of ≥18 years. During the follow-up periods ranging from 5 to 21 years, 39,993 cases of prostate cancer, 5,929 cases of advanced prostate cancer, and 1,661 cases of fatal prostate cancer were detected. In the meta-analysis, we found that higher tissue levels of LA were associated with a reduced risk of prostate cancer (RR: 0.86, 95% CI: 0.77-0.96) so that in the dose-response analysis, each 5% increase in levels of LA was associated with a 14% lower risk of prostate cancer. Such a significant association was not seen for advanced prostate cancer (RR: 0.86, 95% CI: 0.65-1.13). Also, we found no significant association between dietary intake of LA and risk of total (RR:1.00, 95% CI: 0.97-1.04), advanced (RR: 0.98, 95% CI: 0.90-1.07), and fatal prostate cancer (RR: 0.97, 95% CI: 0.83-1.13). Our findings support the protective association between tissue levels of LA and the risk of prostate cancer in men.

Effect of vitamin E intake on glycemic control and insulin resistance in diabetic patients: an updated systematic review and meta-analysis of randomized controlled trials.

Since a 2014 meta-analysis, several randomized controlled trials (RCTs) evaluating the effect of vitamin E intake on glycemic indices and insulin resistance in adults with diabetes have reached inconsistent conclusions. Therefore, we updated the previous meta-analysis to summarize the current evidence in this regard. Online databases including PubMed, Scopus, ISI Web of Science, and Google Scholar were searched to identify relevant studies published up to September 30, 2021, using relevant keywords. Random-effects models were used to obtain overall mean difference (MD) comparing vitamin E intake with a control group. In total, 38 RCTs with a total sample size of 2171 diabetic patients (1110 in vitamin E groups and 1061 in control groups) were included. Combining the results from 28 RCTs on fasting blood glucose, 32 RCTs on HbA1c, 13 RCTs on fasting insulin, and 9 studies on homeostatic model assessment for insulin resistance (HOMA-IR) showed a summary MD of -3.35 mg/dL (95% CI: -8.10 to 1.40, P = 0.16), -0.21% (95% CI: -0.33 to -0.09, P = 0.001), -1.05 µIU/mL (95% CI: -1.53 to -0.58, P < 0.001), and -0.44 (95% CI: -0.82 to -0.05, P = 0.02), respectively. This indicates a significant lowering effect of vitamin E on HbA1c, fasting insulin and HOMA-IR, while no significant effect on fasting blood glucose in diabetic patients. However, in subgroup analyses, we found that vitamin E intake significantly reduced fasting blood glucose in studies with an intervention duration of < 10 weeks. In conclusion, vitamin E intake has a beneficial role in improving HbA1c and insulin resistance in a population with diabetes. Moreover, short-term interventions with vitamin E have resulted in lower fasting blood glucose in these patients. This meta-analysis was registered in PROSPERO with code CRD42022343118.

Fruit and vegetable intake in relation to gastric cancer risk: A comprehensive and updated systematic review and dose-response meta-analysis of cohort studies.

Background: Since the release of previous meta-analyses, some studies on the associations between fruit and vegetable intake with gastric cancer risk have been published. Therefore, we aimed to update the previous meta-analyses on these associations by including recently published studies as well as considering the main limitations of those meta-analyses. Methods: A comprehensive search was conducted in online databases including PubMed, Scopus, ISI Web of Science, and Google Scholar to detect relevant prospective cohort studies published up to October 2021. Summary relative risks (RRs) were estimated using a random-effects model. Results: Overall, 17 articles containing 18 prospective studies with a total sample size of 1,527,995 participants, aged between 18 and 90 years, were included in the current meta-analysis. During the follow-up periods ranging between 4.5 and 21 years, 8,477 cases of gastric cancer were diagnosed. A higher intake of total fruit [RR: 0.87, 95% confidence interval (CI): 0.80 to 0.94, I 2 = 0%] and total fruit and vegetable (RR: 0.75, 95% CI: 0.61 to 0.93, I 2 = 55.2%) were associated with a lower risk of gastric cancer. For total vegetable intake, a significant inverse association was found among the studies that controlled their analysis for energy intake. Based on the linear dose-response analysis, each 100 g/day increase in total fruit intake (Pooled RR: 0.95, 95% CI: 0.90 to 0.99, I 2 = 49%) and 200 g/day increase in total fruit and vegetable intake (RR: 0.94, 95% CI: 0.88 to 0.99, I 2 = 37.6%) were associated with a 5 and 6% lower risk of gastric cancer, respectively. Conclusion: Fruit and vegetable consumption has a protective association with gastric cancer risk.

Associations of abdominal obesity with different types of bone fractures in adults: A systematic review and dose-response meta-analysis of prospective cohort studies.

Findings on the association between abdominal obesity and hip fracture were summarized in a meta-analysis in 2017; however, no study has examined the dose-response association between abdominal fat indices and hip fracture. Also, we found no meta-analysis investigating other types of bone fractures including any vertebral fractures in relation to abdominal obesity. Therefore, the present systematic review and dose-response meta-analysis of prospective cohort studies were conducted to examine the association between abdominal obesity and different types of bone fractures. A comprehensive literature search was done by searching PubMed, Scopus, Web of Science, and Google Scholar until October 2021. In total, 23 articles from prospective cohort studies with a total sample size of 3,456,631 participants were included. During the follow-up periods ranging between 4 and 26 years, 137,989 cases of bone fracture were recorded. After comparing the highest and lowest categories of abdominal fat indices, the summary relative risks (RRs) of any, hip, and vertebral fractures were 0.99 (95% CI: 0.81-1.20), 1.09 (95% CI: 0.82-1.43), and 1.18 (95% CI: 1.05-1.33), respectively, indicating a significant positive association between abdominal obesity and risk of vertebral fracture. In the non-linear dose-response analysis, abdominal obesity based on the waist-to-hip ratio (WHR) was positively associated with an increased risk of hip fracture from 0.7 to 1.1 units of WHR. In the linear analysis, a 10 cm increase in waist circumference (WC) was associated with a 3% higher risk of vertebral fracture. We found no other dose-response association for other types of bone fractures. In conclusion, abdominal obesity may be associated with a higher risk of hip and vertebral fractures.

Soy isoflavone intake and risk of cardiovascular disease in adults: A systematic review and dose-response meta-analysis of prospective cohort studies.

We examined the association between soy isoflavone intake and risk of cardiovascular disease (CVD) outcomes in adults. We searched the online databases for relevant studies published up to September 2021. In total, 13 publications were included in the systematic review and 12 in the meta-analysis. We found that a high intake of soy isoflavones was significantly associated with a lower risk of coronary heart disease (CHD) among whole populations (Pooled RR: 0.92, 95% CI: 0.85-0.99, I2 = 41.0%, Pheterogeneity = 0.10) and a lower risk of overall CVD (Pooled RR: 0.91, 95% CI: 0.84-0.98, I2 = 30.7%, Pheterogeneity = 0.19) and CHD (Pooled RR: 0.89, 95% CI: 0.83-0.96, I2 = 14.4%, Pheterogeneity = 0.32) among Western population. In the linear dose-response analysis, a 3 mg/day increase in soy isoflavone intake was associated with 16% and 14% lower risks of overall CVD and CHD, respectively, among Western population. In conclusion, we found that soy isoflavone intake was associated with a lower risk of overall CVD and CHD in adults, particularly among Western population.

Sugar sweetened beverages, natural fruit juices, and cancer: what we know and what still needs to be assessed.

Cancer is known as one of the leading causes of death in the world. In addition to early mortality, cancer is associated with disability in affected patients. Among environmental risk factors, special attention has been paid to the role of dietary factors. In recent decades, the consumption of sugar-sweetened beverages (SSBs) and natural fruit juices has increased. Several studies have assessed the effects of these beverages on human health and found that a higher intake of SSBs is associated with a greater risk of obesity, diabetes, cardiovascular diseases, hypertension, and non-alcoholic fatty liver disease. However, current evidence for cancer incidence and mortality is not conclusive. In the current review, we concluded that SSBs intake might be positively associated with cancer incidence/mortality through their increasing effects on obesity, inflammatory biomarkers, serum levels of insulin-like growth factor-I (IGF-I), and advanced glycation end-products. Such a positive association was also seen for natural fruit juices. However, types of natural fruit juices were not considered in most previous studies. In addition, some types of cancer including brain, lung, and renal cancers were not assessed in relation to SSBs and natural fruit juices. Therefore, further studies are needed in this regard.