Added γ-oryzanol boosted anti-inflammatory effects of canola oil in adult subjects with type 2 diabetes: a randomized controlled clinical trial.

PURPOSE: This study was conducted to examine the effects of daily intake of γ-oryzanol (ORZ)-fortified canola oil, as compared with plain canola and sunflower oils, on certain inflammatory and oxidative stress biomarkers in adult subjects with Type 2 Diabetes (T2D). METHODS: We randomly allocated 92 adult subjects with T2D from both sexes to one of the following groups to receive: (a) ORZ-fortified canola oil (ORZO; n1 = 30); (b) unfortified canola oil (CANO; n2 = 32); or (c) sunflower oil (SUFO; n3 = 30) for 12 weeks. Dietary and laboratory evaluations were performed initially and finally. RESULTS: Serum hs-CRP concentrations significantly decreased in ORZO group (from 3.1 ± 0.2 to 1.2 ± 0.2 mg/L), as compared with CANO (p = 0.003) and SUFO (p < 0.001) groups. Serum IL-6 significantly decreased just in ORZO (- 22.8%, p = 0.042) and CANO groups (- 19.8%, p = 0.038). However, the between-group differences were not significant. Serum IL-1ß slightly decreased in ORZO (- 28.1%, p = 0.11) and increased in SUFO (+ 20.6%, p = 0.079) but between-group difference was statistically significant (p = 0.017). Serum IFN-γ concentrations decreased significantly only in ORZO (from 3.3 ± 0.08 to 2.9 ± 0.21 IU/mL, p = 0.044). Salivary IgA concentrations increased significantly in all three intervention groups. Notwithstanding, only the difference between ORZO and CANO groups was statistically significant (p = 0.042). Similarly, circulating malondialdehyde concentrations significantly decreased in all three groups but with no between-group significant difference. CONCLUSIONS: Daily consumption of ORZ-fortified canola oil, compared with unfortified canola and sunflower oils, for 12 weeks resulted in boosting of certain anti-inflammatory effects of canola oil. These findings may have preventive implications for both clinicians and policy makers. This clinical trial was registered at clinicaltrials.gov (03.08.2022; NCT05271045).

Improvement of vitamin D status through consumption of either fortified food products or supplement pills increased hemoglobin concentration in adult subjects: Analysis of pooled data from two randomized clinical trials.

Background: It is documented that vitamin D may have a role in erythropoiesis as its deficiency is accompanied by an increased risk of anemia. Aim: This study aimed to examine whether improvement of vitamin D status through daily consumption of either fortified foods or supplements could impinge on certain hematologic parameters in adults. Methods: We pooled data from our two separate clinical trials and made five experimental groups. As part of their usual diet, one group consumed 500 mL/day of yogurt drink fortified with 1000 IU of vitamin D (D-yogurt, n = 27) whereas one group consumed 500 mL/day of the plain yogurt drink (P-yogurt, n = 27). In addition three other groups consumed either 50 g/day bread fortified with 1000 IU of vitamin D (D-bread) or supplement containing 1000 IU vitamin D (D-supplement, n = 27) or placebo (placebo, n = 27). Biochemical measurements were performed before and after the intervention. Results: In all three vitamin D-supplemented groups, serum 25(OH)D concentration increased after the intervention period, which was interestingly accompanied by a significant increment of hemoglobin (D-yogurt, p < 0.001, D-bread, p = 0.003, D-supplement, p < 0.001). Analyses indicated that among participants in vitamin D-intervention groups, being in D-yogurt group was more favourable predictor of improvement in hemoglobin concentrations compared with the placebo (p < 0.001), D-bread (p = 0.045) and P-yogurt (p = 0.001). Conclusion: Improvement of vitamin D status via regular intake of either vitamin D-fortified food products or supplements can result in a significant increment of hemoglobin in adult subjects. This finding has very important clinical as well as public health implications.

Metabolic Syndrome and Its Components are Linked with Increased Risk of Non-Melanoma Skin Cancers in Iranian Subjects: A Case-Control Study.

The associations between components of metabolic syndrome (MetS), insulin resistance (IR), and several malignancies have been reported. However, the possible link between IR and dermal malignancies, including non-melanoma skin cancers (NMSCs), has not been investigated to date. In this study, we aimed to examine the possible association between components of MetS, IR, adhesion molecules, and NMSC for the first time. This was a case-control study comprising 73 confirmed cases of NMSC and 72 unrelated healthy controls. Anthropometric and biochemical assessments including fasting blood lipid profile, glucose and insulin assays were performed. To evaluate IR, HOMA-IR formula was used. Though fasting serum glucose showed no significant between-group difference, serum concentrations of insulin (p = 0.048) as well as HOMA-IR (p = 0.037) were both significantly higher in NMSC group than in controls. Logistic regression analysis revealed significant associations between waist circumference (OR: 1.04, 95% CI: 1.007-1.080, p = 0.018), percent of visceral fat (OR: 1.10, 95% CI: 1.024-1.190, p = 0.01), HOMA-IR (OR: 1.169, 95% CI: 1.004-1.360, p = 0.044), circulating VCAM-1 concentrations (OR: 1.005, 95% CI: 1.003-1.007, p < 0.001) and NMSC risk. Interestingly, the occurrence of MetS was significantly higher in subjects with NMSC than in healthy controls (p = 0.038). MetS and its components were associated with increased NMSC risk.

Development of new predictive equations for basal metabolic rate in Iranian healthy adults: negligible effect of sex.

Some studies have reported inaccuracy of predicting basal metabolic rate (BMR) by using common equations for Asian people. Thus, this study was undertaken to develop new predictive equations for the Iranian community and also to compare their accuracy with the commonly used formulas. Anthropometric measures and thyroid function were evaluated for 267 healthy subjects (18-60 y). Indirect calorimetry (InCal) was performed only for those participants with normal thyroid function tests (n = 252). Comparison of predicted RMR (both kcal/d and kcal.kg.wt-1.d-1) using current predictive formulas and measured RMR revealed that Harris-Benedict and FAO/WHO/UNU significantly over-estimated and Mifflin-St. Jeor significantly under-estimated RMR as compared to InCal measurements. In stepwise regression analysis for developing new equations, the highest r2 (=0.89) was from a model comprising sex, height and weight. However, further analyses revealed that unlike the subjects under 30 y, the association between age and the measured RMR in subjects 30 y and plus was negative (r = -0.241, p = 0.001). As a result, two separate equations were developed for these two age groups. Over 80 percent of variations were covered by the new equations. In conclusion, there were statistical significant under- and over-estimation of RMR using common predictive equations in our subjects. Using the new equations, the accuracy of the calculated RMR increased remarkably.

Vitamin D-fortified cooking oil is an effective way to improve vitamin D status: an institutional efficacy trial.

PURPOSE: High prevalence of vitamin D deficiency (VDD) justifies a cost-effective and sustainable strategy to combat VDD in the community. This study was undertaken for the first time to evaluate the efficacy of daily consumption of vitamin D fortified sunflower oil with a meal. METHODS: This single-blind trial was conducted in two separate institutions: one as intervention (D-fortified sunflower oil) group (DO, n1 = 39) and the other as control (unfortified sunflower oil) group (SO, n2 = 33). Participants consumed their lunches cooked either with D-fortified or unfortified cooking sunflower oil (500 IU/30 g) for 12 weeks. Dietary, anthropometric and biochemical assessments were done for all participants before and after the intervention. RESULTS: A total of 65 subjects from both sexes aged 32.5 ± 4 years completed the intervention period. Serum 25(OH)D showed a significant increase in DO and a decrease in SO group (8.8 ± 9.3 vs. - 7.4 ± 6.4 ng/mL, p < 0.001). The rise in serum 25(OH)D in DO group was accompanied by a significant decrease in iPTH (DO: - 10.2 ± 29.4 vs. SO: + 9.2 ± 29.5 pg/mL; p = 0.009). A significant reduction in weight (p = 0.004), BMI (p = 0.029), waist girth (p < 0.001), serum total cholesterol (p = 0.0290) and LDL-C (p = 0.010) was observed in DO, as compared with SO group. CONCLUSIONS: Cooking oil can be considered as an efficacious vehicle for mass fortification program to combat VDD. The improvement of vitamin D status may bring about betterment of certain cardiometabolic risk factors. REGISTRATION NUMBER: Clinicaltrials.gov: NCT03826654.

Harmonization of serum 25-hydroxycalciferol assay results from high-performance liquid chromatography, enzyme immunoassay, radioimmunoassay, and immunochemiluminescence systems: A multicenter study.

BACKGROUND: Remarkable disagreement among different systems of 25-hydroxy vitamin D 25(OH)D assay makes decision making for both clinical and community interventions very difficult. This study aimed to harmonize the results obtained from different 25(OH)D assay systems. METHODS: A total of 275 serum samples were analyzed for 25(OH)D using DIAsource-enzyme immunoassay (EIA), DIAsource-radioimmunoassay (RIA), Roche-electrochemiluminescence (ECL), Diasorin-chemiluminescent immunoassay (CLIA), and high-performance liquid chromatography (HPLC), as the reference method. Serum intact parathyroid hormone (iPTH) was also measured in all samples. Between-system agreement and harmonization were evaluated using Bland-Altman analysis, receiver operating characteristic (ROC), and regression analysis. RESULTS: Mean serum 25(OH)D concentrations and frequency distribution of vitamin D status showed a significant difference among the studied systems (P<.001 for both). Serum 25(OH)D assay results from all systems correlated with those from HPLC. As compared with HPLC, ECL showed a positive bias (+3.8 nmol/L), whereas CLIA had a negative bias (-11.9 nmol/L). Both EIA and RIA showed a more or less similar positive bias (8.0 and 8.1 nmol/L, respectively). Using serum iPTH-based 25(OH)D cutoff points, only ECL results became comparable to and without significant difference with HPLC. However, when system-specific cutoffs were defined based on HPLC results using regression equations, mean 25(OH)D and frequency distribution of vitamin D status were more harmonized compared with the other methods. CONCLUSION: Our findings showed that with adjustment of circulating 25(OH)D based on HPLC, frequency distribution of vitamin D status, as judged by different methods, can be well harmonized with no statistically significant inter-system difference.

The Prevalence of Zinc Deficiency and its Correlation with Iron Status and Economical Living Area in 9 - 12-Year-Old Children.

OBJECTIVE: This study aimed firstly to assess zinc and iron status of 9-12-year-old children of Tehran and secondly to determine a cut-off for circulating biomarkers of iron status to identify children at increased risk of zinc deficiency. RESEARCH METHODS & PROCEDURES: In a cross-sectional study, demographic and anthropometric data from 505 boys and 467 girls aged 9-12 years from Tehran primary schools were obtained and their zinc and iron status was assessed. RESULTS: The prevalence of zinc deficiency, anemia, and iron depletion was 12.4, 14.6, and 9.5%, respectively. Serum zinc con-centration was significantly lower in children with anemia than in their non-anemic peers (p < 0.05). There was no significant association between zinc and iron status and serum high sensitivity C-reactive protein. Zinc-deficient children, compared to those with normal serum zinc, had significantly shorter stature (139.7 (±6.9) vs 141.3 (±7.1) cm, CI: -2.97 - -0.2, p = 0.029). Serum zinc concentration was the predictor of height in the children (p = 0.004, CI: 0.01 - 0.054). A logistic regression model showed an increased risk of low serum zinc and ferritin in children who resided in economically poor regions (OR = 1.65, p = 0.043; OR = 1.92, p = 0.016, respectively). Using ROC curve and Youden index, the optimal cut-off value for serum ferritin to indicate zinc deficiency was 14.9 µg/L (sensitivity = 90%, specificity = 61%). CONCLUSIONS: Lowered zinc and iron status among the children in deprived regions is likely to be due to poor quality of diet. Moreover, children with serum ferritin lower than 14.9 µg/L must be carefully assessed for concomitant zinc deficiency.

A Vitamin D-Calcium-Fortified Yogurt Drink Decreased Serum PTH but did not Affect Osteocalcin in Subjects with Type 2 Diabetes.

INTRODUCTION: There is sparse evidence of the effect of vitamin D on bone biomarkers in diabetic patients, and therefore, in a randomized clinical trial, we evaluated the effects of the daily intake of vitamin D, either with or without extra calcium, on selected bone biomarkers. MATERIALS AND METHODS: Ninety women and men aged 30 - 50 years old with type 2 diabetes were randomly divided into three groups in a double-blind manner. Group 1 (PD), the control group, received a plain yogurt drink. Groups 2 (DD) and 3 (CDD) received 1000 IU vitamin D3, and 1000 IU vitamin D3 plus 500 mg calcium, respectively, via drinking two 250 mL bottles a day of a fortified yogurt drink for twelve weeks. Anthropometric and biochemical assessments were made, including 25(OH), intact parathyroid hormone (iPTH), osteocalcin, and calcium. RESULTS: Although the time and time × group interaction effects on the bone biomarkers were not statistically significant, there was a modest decrease in iPTH concentrations in both DD and CDD groups over twelve weeks. The subgroups with initial vitamin D deficiency/insufficiency in the CDD group had greater and significant decrease in serum iPTH concentrations after twelve weeks of treatment compared to the PD group (- 9.0 ± 21.2 v.s 8.6 ± 21.8 pg/mL, p = 0.042). CONCLUSION: The improvement in vitamin D status following the daily intake of fortified doogh for twelve weeks was accompanied by a decrement in iPTH, mostly in those subjects with poor initial vitamin D status.

Regular consumption of both vitamin D- and calcium- and vitamin D-fortified yogurt drink is equally accompanied by lowered blood lipoprotein (a) and elevated apoprotein A1 in subjects with type 2 diabetes: a randomized clinical trial.

OBJECTIVE: Cardiovascular disease (CVD) is the major morbidity and cause of death in diabetic subjects. Observational studies have shown the association of low vitamin D status with poor glycemic control, atherogenic lipid profile, and CVD. However, the possible link between circulating 25-hydroxycholecalciferol and apoproteins (Apo A1 and B) and the atherogenic lipoprotein (a) [Lp(a)] has not been documented to date. METHODS: Ninety subjects with type 2 diabetes (T2D) aged 30-60 years from both sexes were randomly allocated to one of the 3 groups to receive 2 bottles a day of either (1) plain doogh (PD; containing 150 mg calcium and no detectable vitamin D/250 mL); (2) vitamin D-fortified doogh (DD; containing 150 mg calcium and 500 IU vitamin D/250 mL); or (3) calcium- and vitamin D-fortified doogh (CDD; containing 250 mg calcium and 500 IU vitamin D/250 mL) for 12 weeks. Anthropometric, dietary, and laboratory assessments, including Apo A1, Apo B, and Lp(a), were done. RESULTS: Improvement of vitamin D status in DD and CDD groups, compared to PD, resulted in a significant increase in Apo A1 (mean changes 0.22 ± 0.38, 0.20 ± 0.27 and 0.01 ± 0.35 g/L, respectively, p = 0.047) and a significant decrease in serum Lp(a) (mean changes -0.08 ± 0.30, -0.08 ± 0.31, and 0.14 ± 0.25 µmol/L, respectively, p = 0.011). There was no significant difference between DD and CDD groups. Serum Apo B did not change significantly in any of the groups. CONCLUSIONS: Significant amelioration of serum Apo A1 and Lp(a) following improvement of vitamin D status in T2D subjects may have preventive implications against long-term diabetic complications, notably CVD. This trial was registered at ClinicalTrials.gov as NTC01229891.

Daily consumption of γ-oryzanol-fortified canola oil, compared with unfortified canola and sunflower oils, resulted in a better improvement of certain cardiometabolic biomarkers of adult subjects with type 2 diabetes: a randomized controlled clinical trial.

BACKGROUND: This study was undertaken to examine the effects of daily consumption of γ-oryzanol (ORZ)-fortified canola oil, as compared with plain canola and sunflower oils, on certain cardiometabolic indicators. METHODS: Ninety-two adult subjects from both sexes with T2D were randomly assigned to one of the three groups to receive: (a) ORZ-fortified canola oil (Group 1; n1 = 30); (b) unfortified canola oil (Group 2; n2 = 32); or (c) sunflower oil (Group 3; n3 = 30) for 12 weeks. The participants were instructed to use only the given oils for all cooking (but frying) purposes. Anthropometric, dietary and biochemical assessments were done initially and finally. RESULTS: Though body mass index (BMI) significantly decreased in all three groups, only in Groups 1 and 2 waist circumference (WC) showed a significant decrement (-2.6 ± 0.1 and -2.2 ± 0.1 cm in Groups 1 and 2 respectively, p < 0.001 for both) which was accompanied by a significant reduction of blood pressure just in Group 1. Fasting blood glucose (FBG) and glycated hemoglobin (HbA1c) showed a significant decrease only in ORZ-fortified canola oil group (-7.7 ± 0.4 mg/dL, p = 0.039 and -0.7 ± 0.1%, p < 0.001, respectively). However, insulin resistance, as judged by HOMA-IR, did not change significantly. In addition, serum triglyceride (TG) concentrations decreased in all three groups but only in ORZ-fortified canola oil was this decrement statistically significant (-17.9 ± 2.1 mg/dL, p = 0.005). Other components of serum lipid profile did not change significantly in either group. CONCLUSIONS: Consumption of either sunflower or canola oils for 12 weeks improved certain studied biomarkers. However, only ORZ-fortified canola oil resulted in a significant decrease of blood pressure, WC, FBG, HbA1c and TG. These findings can help both clinicians and public health authorities for dietary recommendations to subjects with T2D and presumably the whole community. TRIAL REGISTRATION: number at clinicaltrials.gov (NCT05271045).

Improvement of vitamin D status resulted in amelioration of biomarkers of systemic inflammation in the subjects with type 2 diabetes.

BACKGROUND: Both vitamin D deficiency and inflammation have been linked to cardiovascular disease, the major cause of death in diabetes. In this study, the effects of daily intake of vitamin D-fortified yoghourt drink (doogh) on systemic inflammatory biomarkers in subjects with type 2 diabetes (T2D) were investigated. SUBJECTS AND METHODS: In this 12-week randomized controlled trial, T2D subjects received either plain doogh (PD; containing 170 mg calcium and no detectable vitamin D/250 mL, n(1) = 50) or vitamin D3-fortified doogh (FD; containing 170 mg calcium and 500 IU/250 mL, n(2) = 50) twice a day. Glycemic status, body fat mass and systemic inflammatory biomarkers including serum highly sensitive C-reactive protein (hsCRP), serum amyloid A (SAA), interleukin(IL)-2, IL-6, IL-10 and tumour necrosis factor (TNF)-α were evaluated at the beginning and after the intervention. Data were expressed as either mean ± SD or median (interquartile range) whenever they had either normal or non-normal distribution, respectively. RESULTS: In the patients receiving the vitamin D fortified drink, compared with those receiving the unfortified drink, a significant increase in serum 25(OH)D was accompanied by significant changes in TNF-α (-57.9 (-264.6) versus +106.3 (683.2), p = 0.044), IL-6 (-6.3 (-69.2), p = 0.002), hsCRP (-0.39 (-1.50) versus +0.8 (1.52), p < 0.001), SAA (-14.2 ± 44.5 versus +5.6 ± 37.5 mg/L, p = 0.022) and IL-10 (+38.7 ± 157.0 versus -51.9 ± 165.2 ng/L, p = 0.013). The between-group differences of hsCRP, SAA and IL-6 changes remained significant even after controlling for changes quantitative insulin check index (p < 0.001, p < 0.001 and p = 0.009, respectively). CONCLUSIONS: Improvement of vitamin D status of T2D subjects resulted in amelioration of the systemic inflammatory markers. This may have preventive implications against cardiovascular disease and other diabetic complications.

High prevalence of vitamin D deficiency in school-age children in Tehran, 2008: a red alert.

OBJECTIVE: To assess the vitamin D status of 9-12-year-old primary-school children in Tehran during autumn and winter 2007-2008. DESIGN: A descriptive cross-sectional study. SETTING: Primary schools of Tehran city, Iran. SUBJECTS: A total of 1111 children aged 9-12 years (573 boys and 538 girls) from sixty primary schools were enrolled in the study. Weight, height, BMI and serum levels of Ca, P, Mg, 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone (iPTH), osteocalcin and bone-specific alkaline phosphatase of all the participants were assessed. Dietary Ca intake was also evaluated using a quantitative FFQ for a subsample of the study population (n 503). Vitamin D sufficiency was defined on the basis of serum levels of 25(OH)D as either ≥37 nmol/l (criterion 1) or ≥50 nmol/l (criterion 2). RESULTS: Daily intake of Ca did not differ significantly between boys and girls (929·6 (sd 436·7) mg and 909·5 (sd 465·5) mg, respectively). However, on the basis of the first criterion, approximately 86 % of the children had vitamin D deficiency, with 38·3 % being severely deficient (25(OH)D < 12·5 nmol/l). According to the second criterion, prevalence of vitamin D deficiency rose to 91·7 %. Prevalence of vitamin D deficiency was higher in girls than in boys by either criterion. Serum levels of 25(OH)D inversely correlated with iPTH (r = -0·154, P < 0·001) and BMI (r = -0·092, P = 0·002) but directly correlated with duration of sun exposure (r = 0·115, P < 0·001). CONCLUSIONS: The high prevalence of vitamin D deficiency among schoolchildren (especially among girls) warrants immediate interventions for proper nutritional support.

Sun Exposure Makes no Discrimination based on Vitamin D Status and VDR-Foki Polymorphisms for Non-Melanoma Skin Cancers Risk in Iranian Subjects: A Case-Control Study.

BACKGROUND AND OBJECTIVE: Sunlight exposure, the main source of endogenous vitamin D synthesis, may increase the risk of non-melanoma skin cancers (NMSC) development. Vitamin D receptor (VDR) polymorphisms are associated with various malignancies. This study aimed to examine the associations between vitamin D status and VDR FokI polymorphisms in Iranian subjects with NMSC. MATERIALS AND METHODS: This case-control study included 73 diagnosed cases of NMSC and 72 healthy controls from dermatology clinics at Razi Hospital, Tehran, Iran. A questionnaire was used to assess sunlight exposure. The extracted DNA from whole blood samples was genotyped and serum concentrations of 25-hydroxycalciferol (25(OH)D)) and intact parathyroid hormone (iPTH) were measured. RESULTS: We found a significant higher duration of cumulative sunlight exposure in cases compared with controls (p<0.001). However, 25(OH)D and iPTH concentrations were not significantly different between cases and controls (30±15 vs. 29±15 ng/mL, p=0.78 and 46.0±20 vs. 40.5±23 pg/mL, p=0.14, respectively). We did not observe any significant increased risk of NMSC due to f allele, as compared with FF (OR =2.33, 95% CI 0.81-6.75, p=0.12). CONCLUSION: Though sunlight exposure was associated with increased NMSC risk, there were no significant associations between vitamin D status or VDR FokI polymorphisms with NMSC development in our subjects.

Regular consumption of vitamin D-fortified yogurt drink (Doogh) improved endothelial biomarkers in subjects with type 2 diabetes: a randomized double-blind clinical trial.

BACKGROUND: Endothelial dysfunction has been proposed as the underlying cause of diabetic angiopathy that eventually leads to cardiovascular disease, the major cause of death in diabetes. We recently demonstrated the ameliorating effect of regular vitamin D intake on the glycemic status of patients with type 2 diabetes (T2D). In this study, the effects of improvement of vitamin D status on glycemic status, lipid profile and endothelial biomarkers in T2D subjects were investigated. METHODS: Subjects with T2D were randomly allocated to one of the two groups to receive either plain yogurt drink (PYD; containing 170 mg calcium and no vitamin D/250 mL, n1 = 50) or vitamin D3-fortified yogurt drink (FYD; containing 170 mg calcium and 500 IU/250 mL, n2 = 50) twice a day for 12 weeks. Anthropometric measures, glycemic status, lipid profile, body fat mass (FM) and endothelial biomarkers including serum endothelin-1, E-selectin and matrix metalloproteinase (MMP)-9 were evaluated at the beginning and after the 12-week intervention period. RESULTS: The intervention resulted in a significant improvement in fasting glucose, the Quantitative Insulin Check Index (QUICKI), glycated hemoglobin (HbA1c), triacylglycerols, high-density lipoprotein cholesterol (HDL-C), endothelin-1, E-selectin and MMP-9 in FYD compared to PYD (P < 0.05, for all). Interestingly, difference in changes of endothelin-1, E-selectin and MMP-9 concentrations in FYD compared to PYD (-0.35 ± 0.63 versus -0.03 ± 0.55, P = 0.028; -3.8 ± 7.3 versus 0.95 ± 8.3, P = 0.003 and -2.3 ± 3.7 versus 0.44 ± 7.1 ng/mL, respectively, P < 0.05 for all), even after controlling for changes of QUICKI, FM and waist circumference, remained significant for endothelin-1 and MMP-9 (P = 0.009 and P = 0.005, respectively) but disappeared for E-selectin (P = 0.092). On the contrary, after controlling for serum 25(OH)D, the differences disappeared for endothelin-1(P = 0.066) and MMP-9 (P = 0.277) but still remained significant for E-selectin (P = 0.011). CONCLUSIONS: Ameliorated vitamin D status was accompanied by improved glycemic status, lipid profile and endothelial biomarkers in T2D subjects. Our findings suggest both direct and indirect ameliorating effects of vitamin D on the endothelial biomarkers. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01236846.

Effect of latitude on seasonal variations of vitamin D and some cardiometabolic risk factors: national food and nutrition surveillance.

BACKGROUND: Despite a remarkable reduction in the occurrence of many micronutrient deficiencies in most countries, vitamin D deficiency has remained a global problem. Age-adjusted disability-adjusted life years lost due to cardiovascular disease in the Eastern Mediterranean Region, including in the Islamic Republic of Iran, are higher than the global average. AIMS: To assess the effects of latitude and season on vitamin D status in the Iranian population and the association between vitamin D status and certain cardiometabolic risk factors. METHODS: A sample of 1111 participants aged 19-65 years was randomly selected from 6 regions with latitudes ranging from 29º.0 N to 37.5º N. All anthropometric and biochemical assessments were performed twice a year, summer and winter during 2013 to 2014. RESULTS: Overall mean 25(OH)D concentration was 26.9 [standard deviation (SD) 17.8] nmol/L in winter and 43.4 (SD 32.9 nmol/L in summer (P < 0.001). Poor vitamin D status was noticeable in both seasons (90.1% and 69.2%, respectively). Being male (B, 7.6; 95% CI: 4.3 to 10.8; P < 0.001) and living at a latitude higher than 33 ° were positive predictors, and serum 25(OH)D concentration in winter (B, -0.2; 95% CI: -2.9 to -0.11; P < 0.001) was a negative predictor of changes of 25(OH)D concentrations. CONCLUSION: We found a high prevalence of suboptimal vitamin D status in Iranian adults throughout the year, irrespective of latitude and season. Improvement of mean circulating 25(OH)D concentrations in the community to 50+ nmol/L through a fortification programme is likely to engender healthy cardiometabolic changes.

Regular daily intake of black tea improves oxidative stress biomarkers and decreases serum C-reactive protein levels in type 2 diabetic patients.

BACKGROUND: This study was undertaken to evaluate the possible effects of different daily doses of black tea intake on certain oxidative stress, inflammatory and metabolic biomarkers in patients with type 2 diabetes mellitus (T2DM). METHODS: Forty-six patients with known T2DM were randomly assigned either to the test (n = 23, 57.0 +/- 7.9 years) or the control (n = 23, 55.4 +/- 8.3 years) group. Following a one-week 'run-in' period, the test group received 150, 300, 450 and 600 ml of black tea extract (BTE) during the weeks 1, 2, 3 and 4, respectively. The control group received 150 ml BTE a day throughout the intervention period. Dietary, anthropometric and biochemical assessments were performed at the end of each week. FINDINGS: Serum total antioxidant capacity was enhanced similarly in both test and control groups. However, daily intake of 2 cups of BTE by the test group showed a suppressing effect on serum malondialdehyde. Serum C-reactive protein significantly decreased and glutathione levels increased following the intake of 4 cups (600 ml) of BTE a day. CONCLUSION: Regular intake of BTE had anti-oxidative and anti-inflammatory effects in patients with T2DM. These findings may, to some extent, explain the mechanisms underlying the protective effects of drinking tea against cardiovascular disease.

Selective effects of tea extract and its phenolic compounds on human peripheral blood mononuclear cell cytokine secretions.

BACKGROUND: The effects of black tea extract (BTE) and some of its pure phenolics on human peripheral blood mononuclear cell (PBMC) cytokine secretion were examined in vitro. MATERIALS AND METHODS: The main steps of the study included chromatographic analysis of BTE and commercial green tea extract, Polyphenon 60, determination of the total antioxidant capacity of both the extracts and their phenolics, and finally evaluation of their effects on PBMCs. FINDINGS: Four major peaks in the chromatogram of BTE belonged to caffeine, gallic acid, epigallocatechin and epigallocatechin gallate, and the latter showed the highest antioxidant capacity. While pure phenolics at the concentration of 20 mM did not significantly affect PBMC cytokine secretion, BTE and Polyphenon 60 suppressed interleukin-1 beta, tumor necrosis factor-alpha and interleukin-6. Interestingly, the secretion of interferon-gamma after 24 h was slightly, but significantly, boosted by the extracts. CONCLUSION: BTE has selective pro-inflammatory cytokine-suppressing effects on human PBMCs.

Efficacy of Vitamin D Supplementation in Physical Performance of Iranian Elite Athletes.

BACKGROUND: There has been no report of the vitamin D status of the professional athletes from Iran to date. This study was performed to evaluate the efficacy of weekly vitamin D supplementation on athletic performance in Iranian athletes expedited to Asian competition in Taipei, China, 2015. METHODS: This study was a randomized controlled clinical trial. Seventy subjects were enrolled in the study. The athletes were randomly divided into two groups: vitamin D supplement (D; received 50,000 IU of vitamin D supplement weekly) and control (P, received a placebo weekly). Duration of the study was 8 weeks. Anthropometric, dietary, athletic performance, and biochemical evaluations were performed for all subjects in the beginning and in the end of the intervention period. RESULTS: A significant rise in circulating 25(OH)D concentration was observed in D group (17.3 ± 16.9 ng/mL, P < 0.001), whereas in P group, there was a statistically significant decrement (-3.1 ± 8.4 ng/mL, P = 0.040). There were no either within- or between-group significant differences in Ergo jump, vertical jump, and agility tests. In strength leg press tests, both groups showed a significant improvement. However, comparisons of changes revealed that the improvement in D group was significantly higher than in P group (P = 0.034). Moreover, in sprint test (one repetition-Max, 1RM), only D group had a significant within-group improvement (P = 0.030). CONCLUSIONS: Weekly supplementation with 50,000 IU vitamin D resulted in nearly 17 ng/mL increment in circulating calcidiol. This increase was associated with significant improvement of power leg press and sprint tests in D-supplemented group.

Determination of serum 25-hydroxy cholecalciferol using high-performance liquid chromatography: a reliable tool for assessment of vitamin D status.

This study was undertaken to design and set up a rather simple, reliable, and less expensive high-performance liquid chromatography (HPLC)-based method to assay 25(OH)D as a diagnostic tool for vitamin D assessment. Serum proteins were precipitated using ethanol and, after 10 minutes incubation at room temperature, methanol:isopropanol. The extraction was performed using hexane followed by evaporation under nitrogen flow. The sediment was then reconstituted in methanol and passed through a polypropylene filter. To run the chromatographic analysis, 20 microL of the filtrate was injected to the column. Peaks of 25(OH)D2 and 25(OH)D3 were both detected using a UV detector set at 265 nm. With a flow rate of 1.2 mL/minute, peaks of D3 and D2 vitamers were detected around 9.5 and 10.7 minutes, respectively. The intra- and inter-assay variations were 8.1% and 12.6%, respectively, and the recovery percent was found to be 100 +/- 5%. To compare the procedure with conventional methods, 90 serum samples from subjects (48 females and 42 males) aged 40.5 +/- 13.9 yrs, were analyzed for 25(OH)D using HPLC, competitive protein-binding assay (CPBA), and radioimmunoassay (RIA). Generally, CPBA and RIA assays both showed over-estimation of serum 25(OH)D, compared to HPLC. Though all three methods correlated significantly with each other, with the strongest between HPLC and RIA (r = 0.87, p < 0.001), both RIA and CPBA were found unreliable in detection of some deficient samples.

Vitamin D-Fortified Bread Is as Effective as Supplement in Improving Vitamin D Status: A Randomized Clinical Trial.

CONTEXT: Bread can potentially be a suitable vehicle for fortification with vitamin D. OBJECTIVE: This study was undertaken to evaluate the following: 1) the bioavailability of vitamin D from the fortified Iranian bread and 2) the possible effects of daily consumption of the fortified bread on certain health aspects. DESIGN, SETTING, AND PARTICIPANTS: This was a randomized, double-blind, placebo-controlled trial conducted over 8 weeks in 90 healthy subjects aged 20-60 years. INTERVENTION: Subjects were randomly allocated to one of three groups: 1) fortified bread (FP; 50 g bread fortified with 25 µg vitamin D3 plus placebo daily; n = 30); 2) supplement (SP; 50 g plain bread plus 25 µg vitamin D supplement daily; n = 30); and 3) control (CP; 50 g plain bread plus placebo daily; n = 30). OUTCOME MEASURES: Initial and final anthropometric and biochemical assessments were performed. RESULTS: The within-group changes of serum 25-hydroxyvitamin D concentrations were 39.0 ± 22.6 (P < .001), 28.9 ± 31.2 (P < .001), and -9.2 ± 12.3 nmol/L in the FP, SP, and CP groups, respectively. Only in FP and SP groups, serum intact PTH concentrations decreased approximately 13.5% and 14.5%, respectively. Visceral fat also showed a significant decrement in FP (-1.05% ± 1.4%; P ≤ .001) and SP (-0.96% ± 1.7%; P = .006). Serum low-density lipoprotein cholesterol concentration showed a within-group reduction in FP (-10.4 ± 11.2 mg/dL; P < .001) and an insignificant decrement in SP (-6.6 ± 20.2 mg/dL; P = .083). Serum high-density lipoprotein increased in both vitamin D-supplemented groups (FP: 9.7 ± 7.6 vs SP: 5.7 ± 6.7 mg/dL; P < .001). CONCLUSION: Vitamin D-fortified bread could be potentially effective in raising circulating 25-hydroxyvitamin D levels of the population to nearly adequate levels.