Effect Of Vitamin D3 Supplementation Research Articles

Vitamin D Improves Selected Metabolic Parameters but Not Neuropsychological or Quality of Life Indices in OSA: A Pilot Study.

Our group and others have reported a high rate of vitamin D deficiency in obstructive sleep apnea (OSA), where vitamin D levels (25(OH) D) correlate negatively with OSA severity and some of its associated metabolic alterations. Data regarding vitamin D supplementation in OSA are lacking. We wanted to evaluate the effect of vitamin D3 supplementation on OSA symptoms and metabolic parameters. We conducted a pilot, double-blind, randomized, placebo-controlled trial of daily supplementation with 4,000 IU vitamin D3 (D3) or placebo (PL). We studied 19 Caucasian adults (14 male, mean age 55 y, mean body mass index [BMI] 30.4 kg/m2) with OSA. Fifteen patients were stable on continuous positive airways pressure (CPAP) therapy, whereas four were CPAP naïve. Assessments were completed at baseline and after 15 weeks of supplementation. Outcomes included sleepiness (Epworth Sleepiness Scale), quality of life (Sleep Apnea Quality of Life Inventory), fatigue (fatigue severity scale) and neuropsychological function (trail making test and Connor's Continuous Performance Test II). In addition, we assessed biochemical indices of vitamin D status (25(OH)D, calcium), inflammation (high sensitivity C-reactive protein, and lipoprotein-associated phospholipase A2), lipids (total cholesterol [low-density and high-density lipoprotein]) and glycemic indices (fasting glucose, oral glucose tolerance test). There was no change in BMI, medication, or CPAP usage. Although there was no change in neuropsychological or quality of life indices, we observed a significant increase in 25(OH)D (p = 0.00001) and significant decreases in both low-density lipoprotein (p = 0.04) and lipoprotein-associated phospholipase A2 (p = 0.037) as well as trends toward decreased fasting glucose (p = 0.09) and increased high-density lipoprotein (p = 0.07) in the D3 group compared to PL. Vitamin D3 supplementation increased vitamin D levels and decreased metabolic markers compared to placebo. Larger trials are required.

Vitamin D Modulates Hematological Parameters and Cell Migration into Peritoneal and Pulmonary Cavities in Alloxan-Diabetic Mice.

Background/Aims. The effects of cholecalciferol supplementation on the course of diabetes in humans and animals need to be better understood. Therefore, this study investigated the effect of short-term cholecalciferol supplementation on biochemical and hematological parameters in mice. Methods. Male diabetic (alloxan, 60 mg/kg i.v., 10 days) and nondiabetic mice were supplemented with cholecalciferol for seven days. The following parameters were determined: serum levels of 25-hydroxyvitamin D, phosphorus, calcium, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, red blood cell count, white blood cell count (WBC), hematocrit, hemoglobin, differential cell counts of peritoneal lavage (PeL), and bronchoalveolar lavage (BAL) fluids and morphological analysis of lung, kidney, and liver tissues. Results. Relative to controls, cholecalciferol supplementation increased serum levels of 25-hydroxyvitamin D, calcium, hemoglobin, hematocrit, and red blood cell counts and decreased leukocyte cell counts of PeL and BAL fluids in diabetic mice. Diabetic mice that were not treated with cholecalciferol had lower serum calcium and albumin levels and hemoglobin, WBC, and mononuclear blood cell counts and higher serum creatinine and urea levels than controls. Conclusion. Our results suggest that cholecalciferol supplementation improves the hematological parameters and reduces leukocyte migration into the PeL and BAL lavage of diabetic mice.

Vitamin D, cell death pathways, and tuberculosis.

Mycobacterium tuberculosis induces cellular necrosis that could promote spread of infection. The aim of this study is to analyze the effects of Vitamin D3 supplementation to improve the effectiveness of 2nd-line anti-tuberculosis (TB) drug therapy, especially in relation with cell death pathways. Mus musculus C3HeB/FeJ was randomly divided into four groups containing eight animals each. The 1st group (G1), consisting of mice that were intratracheally infected with multidrug-resistant strain of M. tuberculosis and sacrificed on 2-week postinfection to confirm successful infection. (G2) was a group of TB mice without therapy. Then, (G3) was a group of mice with the 2nd-line anti-TB therapy. The last group (G4) was a group of mice receiving not only the 2nd-line anti-TB therapy but also daily oral Vitamin D3 supplementation. Immunohistochemistry was used to measure expression of nuclear Vitamin D receptor, apoptosis marker cleaved caspase-3, cathelin-related antimicrobial peptide (CRAMP) and LC3B autophagy markers, necrosis marker RIPK3, and collagenase matrix metalloproteinase-1 (MMP1). The number of bacteria in the lung was calculated by colony forming units. The partial least square structural equation modeling with SmartPLS 3.2.6 software was used to analyze structural models among the variables. Supplementation of Vitamin D3 on the 2nd-line anti-TB therapy increases Vitamin D3 receptor, CRAMP, LC3B, caspase-3 (P = 0.026, P = 0.000, P= 0.001), presses MMP1, and the number of bacteria (P = 0.010 and P= 0.000, respectively). The structural equation modeling analysis shows that increasing autophagy pathways reduces necrosis by lowering MMP1, whereas apoptosis reduces necrosis by decreasing the number of bacteria (each with indirect effects - 0.543 and - 0.544). A comprehensive analysis with the partial least square structural equation modeling shows decreasing necrosis requires increasing autophagy and apoptosis.

Vitamin D Receptor Genotype, Vitamin D3 Supplementation, and Risk of Colorectal Adenomas

Despite epidemiological and preclinical evidence suggesting that vitamin D and calcium inhibit colorectal carcinogenesis, daily supplementation with these nutrients for 3 to 5 years was not found to significantly reduce the risk of recurrent colorectal adenomas in a recent randomized clinical trial. To investigate whether common variants in 7 vitamin D and calcium pathway genes (VDR, GC, DHCR7, CYP2R1, CYP27B1, CYP24A1, and CASR) modify the effects of vitamin D3 or calcium supplementation on colorectal adenoma recurrence. We examined 41 candidate single-nucleotide polymorphisms (SNPs) in 2259 participants in a randomized, double-blind, placebo-controlled trial conducted at 11 clinical centers in the United States. Eligibility criteria included a recently diagnosed adenoma and no remaining colorectal polyps after complete colonoscopy. The study's treatment phase ended on August 31, 2013, and the analysis for the present study took place from July 28, 2014, to October 19, 2016. Daily oral supplementation with vitamin D3 (1000 IU) or calcium carbonate (1200 mg elemental calcium) or both or neither. The outcomes assessed were the occurrence of 1 or more adenomas or advanced adenomas (estimated diameter, ≥1 cm; or with villous histologic findings, high-grade dysplasia, or cancer) during follow-up. Treatment effects and genotype associations and interactions were estimated as adjusted risk ratios (RRs) and 95% confidence intervals (CIs). The effective number of independent SNPs was calculated to correct for multiple testing. Among the 2259 participants randomized, 1702 were non-Hispanic whites who completed the trial and had genotype data for analysis (1101 men; mean [SD] age 58.1 [6.8] years). The effect of vitamin D3 supplementation on advanced adenomas, but not on adenoma risk overall, significantly varied according to genotype at 2 VDR SNPs (rs7968585 and rs731236) in linkage disequilibrium (D' = 0.98; r2 = 0.6). For rs7968585, among individuals with the AA genotype (26%), vitamin D3 supplementation reduced risk by 64% (RR, 0.36; 95% CI, 0.19-0.69; P = .002; absolute risk decreased from 14.4% to 5.1%). Among individuals with 1 or 2 G alleles (74%), vitamin D3 supplementation increased risk by 41% (RR, 1.41; 95% CI, 0.99-2.00; P = .05; absolute risk increased from 7.7% to 11.1%; P < .001 for interaction). There were no significant interactions of genotypes with calcium supplementation. Our findings suggest that benefits from vitamin D3 supplementation for the prevention of advanced colorectal adenomas may vary according to vitamin D receptor genotype. clinicaltrials.gov Identifier: NCT00153816.

Vitamin D3 Supplementation During Pregnancy and Lactation Improves Vitamin D Status of the Mother–Infant Dyad

ObjectiveTo identify the combined effect of prenatal and postnatal vitamin D3 supplementation on the vitamin D status of pregnant and lactating women and their exclusively breastfed infants. DesignDouble-blind, randomized controlled trial. SettingUpper Midwestern U.S., hospital-based obstetric practice. ParticipantsPregnant women (N = 13) planning to exclusively breastfeed were randomized at 24 to 28 weeks gestation to receive vitamin D3 at a dosage of 400 IU (control group, n = 6) or 3,800 IU (intervention group, n = 7) daily through 4 to 6 weeks postpartum. Vitamin D status was determined at enrollment and in mother–infant dyads at 24 to 72 hours after birth and 4 to 6 weeks postpartum. MethodsSerum 25-hydroxyvitamin D levels were measured to determine the effect of vitamin D3 supplementation on the vitamin D status of mothers and infants. Analysis of covariance was used to compare differences in 25-hydroxyvitamin D levels between the control and intervention groups. ResultsThe mothers’ vitamin D levels were significantly higher in the intervention group than in the control group at birth (p = .044) and at 4 to 6 weeks postpartum (p = .002). Infants in the intervention group had significantly higher vitamin D levels at birth (p = .021) and nonsignificant, clinically relevant increases at 4 to 6 weeks of age (p = .256). No differences were found between maternal groups in serum calcium or parathyroid hormone levels. ConclusionPrenatal to postpartum vitamin D3 supplementation is an effective intervention to increase a mother’s vitamin D status and to promote optimal vitamin D status in newborns and exclusively breastfed infants.

Effect of Vitamin D3 Supplementation on Respiratory Tract Infections in Healthy Individuals: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

ObjectiveVitamin D supplementation may be a simple preventive measure against respiratory tract infections (RTIs) but evidence from randomized controlled trials is inconclusive. We aimed to systematically summarize results from interventions studying the protective effect of vitamin D supplementation on clinical and laboratory confirmed RTIs in healthy adults and children.MethodsMedline, EMBASE, CENTRAL, and CINAHL were screened from inception until present (last updated in January 2016) completed by a search of the grey literature, clinical trial registers and conference abstracts. We included randomized trials comparing vitamin D versus placebo or no treatment. Two independent reviewers were responsible for study selection and data extraction. Cochrane’s risk of bias tool and the GRADE approach were used for quality assessment. Estimates were pooled with random-effects models. Heterogeneity was explored by sub-group and meta-regression analyses.ResultsOf 2627 original hits, 15 trials including 7053 individuals were ultimately eligible. All used oral cholecalciferol. We found a 6% risk reduction with vitamin D3 supplementation on clinical RTIs, but the result was not statistically significant (RR 0.94; 95% CI 0.88 to 1.00). Heterogeneity was large (I-square 57%) and overall study quality was low. There were too few studies to reliably assess a potential risk reduction of laboratory confirmed RTI. Evidence was insufficient to demonstrate an association between vitamin D supplementation and risk of clinical RTI in sub-groups with vitamin D deficiency.ConclusionsIn previously healthy individuals vitamin D supplementation does not reduce the risk of clinical RTIs. However, this conclusion is based on a meta-analysis where the included studies differed with respect to population, baseline vitamin D levels and study length. This needs to be considered when interpreting the results. Future trials should focus on vitamin D deficient individuals and apply more objective and standardized outcome measurements.

A randomized controlled trial of vitamin D supplementation on perinatal depression: in Iranian pregnant mothers.

BackgroundMood disorders in pregnancy and post-partum period are common and considered as a public health issue. Researchers have studied the relationship between low serum vitamin D concentration and perinatal depression, although no clinical trial has been conducted on vitamin D’s effects on depression related to childbirth. This study evaluated the effect of vitamin D3 supplementation on perinatal depression scores.MethodsThis randomized clinical trial was done in pregnant women who were under prenatal care in a teaching hospital in Shiraz, Iran. The inclusion criteria were: being 18 years or older, no history of mental illness and internal diseases, a singleton live fetus, without any pregnancy complications, gestational age of 26–28 weeks upon enrollment, and depression score of 0 to 13. The Edinburgh Postnatal Depression scale was used to evaluate depression scores. A total of 169 participants were assigned to the two groups of placebo and vitamin D through block randomization design. Vitamin D group received 2000 IU vitamin D3 daily from 26 to 28 weeks of gestation until childbirth. Maternal serum 25-hydroxyvitamin D concentrations were measured at baseline and childbirth. Besides, depression scores were evaluated four times: at 26–28 and 38–40 weeks of gestation, and finally at 4 and 8 weeks after birth.ResultsThe two groups were similar in relation to baseline 25-hydroxyvitamin D concentrations. However, at childbirth, the vitamin D group had significantly higher 25-hydroxyvitamin D concentration in comparison to the control group (p < 0.001). At baseline, no correlation was observed between 25-hydroxyvitamin D concentration and depression score (r = 0.13, p = 0.09). There was no significant difference between the two study groups in relation to the baseline depression score. While, the vitamin D group had greater reduction in depression scores than the control group at 38–40 weeks of gestation (p = 0.01) also, at 4 and 8 weeks after birth (p < 0.001).ConclusionsThe present trial showed that consuming 2000 IU vitamin D3 daily during late pregnancy was effective in decreasing perinatal depression levels. We suggest further clinical trial in pregnant mothers who are at risk for postnatal depression.Trial registrationIranian Registry of Clinical Trials IRCT2015020310327N11. Date of registration: March 9th 2015.Electronic supplementary materialThe online version of this article (doi:10.1186/s12884-016-1024-7) contains supplementary material, which is available to authorized users.

Acute Effects of Vitamin D3 Supplementation on Muscle Strength in Judoka Athletes

Indoor athletes have been shown to be prone to vitamin D3 deficiency. The aim of the study was to examine the acute effects of vitamin D supplementation on muscle function using isokinetic dynamometry. Randomized placebo-controlled, double-blind study. Institutional. Adult male white national level judoka athletes (n = 22) who were involved in full-time training. Exclusion criteria were vitamin supplementation, overseas travel to sunny climes, and/or an injury incurred during the last 3 months before testing. Subjects were randomly allocated to the treatment (150 000IU vitamin D3) or placebo and given blinded supplements by an independent researcher. Participants were tested twice, 8 days apart, on a Monday morning before the start of judo training and after 2 days of rest. A 5 to 7 mL of blood sample was collected followed by isokinetic concentric quadriceps and hamstring muscle function assessments on the right leg at 30 and 200°·s. Repeated-measures analysis of variance was used to analyze isokinetic muscle force and serum 25(OH)D3. Regression to the mean was used to examine changes in 25(OH)D3 levels over the study period. The treatment group demonstrated a significant increase in serum 25(OH)D levels (34%, P ≤ 0.001) and muscle strength (13%, P = 0.01) between days 1 and 8. No significant differences were found for the placebo group for the same period. A single bolus of 150 000IU vitamin D3 had a significant positive effect on serum 25(OH)D levels and muscle function in vitamin D insufficient elite indoor athletes. Serum 25(OH)D3 levels of indoor athletes should be monitored throughout the year and especially during winter months. Beneficial responses, in muscle strength and serum 25(OH)D3, to 1 dose of vitamin D3 supplementation can be observed within 1 week of ingestion. Muscle strength is linked to serum 25(OH)D levels.

YI-10 - Effect of vitamin D3 supplementation on metal and redox homeostasis in hormone treated prostate cancer patients

YI-10 - Effect of vitamin D3 supplementation on metal and redox homeostasis in hormone treated prostate cancer patients

Effects of vitamin D supplementation during weight loss on sex hormones in postmenopausal women.

The aim of the study was to compare the effects of vitamin D3 supplementation versus placebo on serum sex hormones in postmenopausal women completing a 12-month diet + exercise weight loss program. Two hundred eighteen overweight or obese women (50-75 y) with serum 25-hydroxyvitamin D at least 10 to less than 32 ng/mL ("insufficient") were randomized to either weight loss + 2,000 IU/day oral vitamin D3, or to weight loss + daily placebo. Serum sex hormone-binding globulin, estrone, total, free, and bioavailable estradiol, and testosterone were measured by radioimmunoassay before randomization and at 12 months. Mean changes were compared between groups (intent-to-treat) using generalized estimating equations. The 12-month changes in sex hormone-binding globulin, estrone, total, free, and bioavailable estradiol, and testosterone did not differ between groups (all P > 0.05). However, a greater increase in serum 25-hydroxyvitamin D was associated with a greater increase in sex hormone-binding globulin (Ptrend = 0.01), and larger decreases in free and bioavailable estradiol (Ptrend = 0.04, Ptrend = 0.03, respectively). In post-hoc analyses, we compared women randomized to vitamin D whose serum 25-hydroxyvitamin D remained insufficient (n = 38), to women who became replete (25-hydroxyvitamin D ≥32 ng/mL; n = 53). Replete women showed greater reductions in bioavailable estradiol (-1.8 vs -0.7 pg/mL), free testosterone (-0.8 vs -0.3 pg/mL), and bioavailable testosterone (-1.8 vs -0.6 ng/dL), and a greater increase in sex hormone-binding globulin (10.6 vs 4.7 nmol/L) (all P < 0.05), even after adjusting for differences in total 12-month weight loss. Overall, 12-month changes in sex hormone did not differ between groups. However, vitamin D repletion was associated with greater reductions in sex hormones during weight loss, with a possible dose-dependent effect. Future studies should test higher doses and target circulating 25-hydroxyvitamin D levels when measuring such effects.

Effect of cholecalciferol supplementation on arterial stiffness: a systematic review and meta-analysis

Background: Vitamin D deficiency increases risk of cardiovascular diseases, arterial stiffness, and endothelial dysfunction. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) investigating the impact of vitamin D supplementation on arterial stiffness.Methods: A comprehensive search of the databases of the Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE was performed from inception through November 2015. The inclusion criterion was RCTs that assessed the impact of cholecalciferol supplementation in adults on the surrogate markers of arterial stiffness (aortic pulse wave velocity (PWV) and augmentation index (AIx)). Outcome was the pooled mean difference (MD) of PWV and AIx between the vitamin D supplementation (intervention) group and placebo.Results: The initial search yielded 1164 articles. Twenty-eight articles underwent full-length review and data were extracted from seven RCTs involving totally 547 participants. Dose of cholecalciferol supplementation varied from 1000 IU/day to 120,000 IU/month of cholecalciferol. Duration of treatment ranged from 2 to 12 months. There was no significant difference in the change of PWV (pooled MD = 0.18, 95% CI: −0.17 to 0.52 or AIx (pooled MD = 2.39, 95% CI: −4.43 to 4.92) between the intervention group and placebo.Conclusions: There was no improvement of markers of arterial stiffness after vitamin D supplementation.

Effect of Vitamin D3 Supplementation on Inflammatory Markers and Glycemic Measures among Overweight or Obese Adults: A Systematic Review of Randomized Controlled Trials.

BackgroundObesity induced low-grade chronic inflammation disrupts proper immune and metabolic function. Vitamin D deficiency increases inflammation, which is associated with cardiometabolic risk. This systematic review examines the association between oral vitamin D (VD) supplementation and circulating inflammatory biomarkers and glycemic outcomes from randomized controlled trials (RCTs) of overweight and/or obese adults.MethodsMEDLINE OVID, EMBASE and the Cochrane Central Register of Controlled Trials were searched according to a predefined protocol. Eligible RCTs included adults randomized to receive either oral VD or placebo. Two reviewers independently assessed RCTs for inclusion. Bias was assessed using the Cochrane Collaboration risk of bias tool. Mean differences were calculated comparing end-of-study sample means between the independent VD and placebo groups.ResultsEleven unique RCTs met inclusion criteria from a total of 3,383 identified citations, including 79 screened articles and 14 full text data extractions. Inflammatory and glycemic measures were reported in 7 and 10 RCTs, respectively. Most trial findings were non-significant with considerable heterogeneity in design, participants and outcomes. All but one trial was rated as either high or unclear risk of bias. Two RCTs reported significant changes in inflammatory biomarkers; however, the mean difference between groups was not statistically significant: C-reactive protein 0.19 mg/L (p = 0.88); Tumor Necrosis Factor -0.54 pg/ml (p = 0.20). Two other trials found significant mean differences in fasting plasma glucose -0.32 mmol/L (p = 0.03), Hemoglobin A1c -0.13% (p = 0.04), and Homeostatic Model Assessment -0.86 (p = 0.02) following VD supplementation.ConclusionsOverall, there is no clear established benefit of VD supplementation on inflammatory biomarkers among overweight/obese adults. Baseline serum VD possibly influences the effect of VD repletion on inflammatory markers. Risk of bias was present in most studies, thus supporting the need for higher quality studies in this area to more conclusively understand the role VD supplementation has on inflammatory pathways.

Effect of vitamin D3 supplementation on blood pressure in adults: An updated meta-analysis

Background and aimsPrevious randomized clinical trials (RCTs) of the effects of vitamin D3 supplementation (VD3S) on blood pressure have generated inconsistent results. We evaluated the effect of VD3S on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in a meta-analysis. Data synthesisLiterature searches of PubMed, Scopus, Ovid, and Google scholar for publications in English were conducted up to April 2015. RCTs that assessed the effect of VD3S on SBP and DBP were selected. ConclusionsA total of 30 RCTs with 41 arms including 4744 participants were included. The mean duration of the studies was 5.6 ± 4.0 months, and doses of VD3S varied between 200 and 12,000 IU/day. VD3S had no effect on SBP (−0.68 mmHg, 95%CI: −2.19 to 0.84), and DBP (−0.57 mmHg, 95%CI: −1.36 to 0.22). Subgroup analysis revealed that daily vitamin D3 therapy at a dose of >800 IU/day for <6 months in subjects ≥50 years old reduced both SBP and DBP (p < 0.001). In addition, VD3S showed hypotensive effects in healthy subjects and hypertensive patients, but a hypertensive effect in overweight and obese subjects. However, after excluding overweight and obese subjects, VD3S significantly reduced SBP and DBP. VD3S in combination with calcium supplementation significantly elevated SBP (3.64 mmHg, 95%CI: 3.15–4.13) and DBP (1.71 mmHg, 95%CI: 1.25–2.18). No evidence of publication bias was found. The effects of VD3S on blood pressure depend on dose of supplementation, treatment regimens, trial duration, and population subgroup. Supplementation may be beneficial at daily doses >800 IU/day for <6 months in subjects ≥50 years old.

Effect of Vitamin D3 Supplementation on Telomerase Activity in Hispanics with Type 2 Diabetes

SignificanceLow levels of telomerase activity create short telomeres, which in turn signal exit from the cell cycle, cell senescence and apoptosis. Low telomerase activity and short telomere length are linked to type 2 diabetes and mortality. Hispanics are shown to have shorter telomere lengths as compared to Whites. Hispanics are also at high risk for type 2 diabetes and vitamin D deficiency.ObjectiveThis study investigated whether daily vitamin D3 supplementation at 4000 IU can increase telomerase activity over time in Hispanics with type 2 diabetes and hypovitaminosis D (25‐hydroxy vitamin D &lt; 30 ng/mL).MethodsParticipants (n=34) were recruited from two clinics in Miami‐Dade County, FL, US (Borinquen Health Care Center and Clinical Care Medical Center). Twenty milliliters of venous blood (at least 8 hours fasting) was collected from each participant by a certified phlebotomist using standard laboratory methods. Serum 25‐hydroxy vitamin D levels were determined using a commercial ELISA kit from Immunodiagnostic Systems Limited (Scottsdale, AZ, USA). Telomerase activity was assayed by the TeloTAGGG Telomerase PCR ELISA kit (Roche Applied Science, Indianapolis, IN, USA). Final quantified telomerase activity levels were expressed as Relative Telomerase Activities (RTA). Participants were given 4000 IU/day of vitamin D3 supplementation for 6 months. All data analyses were conducted on an “intent to treat” basis. Statistical analysis included descriptive statistics and one‐way repeated‐measures ANOVA.ResultsMean levels for telomerase activity differed statistically significantly between time points (F(2,66) = 78.57), p &lt; 0.001). Post hoc test using Bonferroni correction indicated that telomerase activity levels increased from baseline to 6 months (49.3 ± 6.8 vs. 63.1 ± 7.2 RTA, respectively) which was statistically significant (p &lt; 0.001). However, baseline to 3 months telomerase activity levels (49.3 ± 6.8 vs. 45.9 ± 3.9 RTA, respectively) were not statistically significant (p = 0.068).ConclusionVitamin D3 supplementation at 4000 IU/day significantly increased telomerase activity in Hispanics with type 2 diabetes. Vitamin D3 supplementation may prevent/delay disease progression in type 2 diabetes through telomerase re‐activation and maintenance of DNA. Larger randomized controlled trials are needed to confirm these results in this and other racial/ethnic groups.

Effects of Vitamin D3 Supplementation on Lean Mass, Muscle Strength, and Bone Mineral Density During Weight Loss: A Double-Blind Randomized Controlled Trial.

To compare the effects of 12 months of vitamin D3 supplementation with that placebo on lean mass, bone mineral density (BMD), and muscle strength in overweight or obese postmenopausal women completing a structured weight-loss program. Double-blind, placebo-controlled randomized clinical trial. Fred Hutchinson Cancer Research Center, Seattle, Washington. Postmenopausal women aged 50 to 75 with a body mass index (BMI) of 25 kg/m(2) or greater and a serum 25-hydroxyvitamin D (25(OH)D) concentration between 10.0 and 32.0 ng/mL (insufficient) (N = 218). Oral vitamin D3 2,000 IU/d or placebo in combination with a lifestyle-based weight loss intervention consisting of a reduction of 500 kcal to 1,000 kcal per day and 225 min/wk of moderate- to vigorous-intensity aerobic exercise. Serum 25(OH)D, body composition, and muscle strength were measured before randomization (baseline) and at 12 months. Mean changes of the groups were compared (intention to treat) using generalized estimating equations. Change in 25(OH)D was significantly different between the vitamin D and placebo groups at 12 months (13.6 ng/mL vs -1.3 ng/mL, P < .001), but no differences in change in lean mass (-0.8 kg vs -1.1 kg, P = .53) or BMD of the spine (-0.01 g/cm(2) vs 0.0 g/cm(2) , P = .82) or right femoral neck (both -0.01 g/cm(2) , P = .49) were detected between the groups. Leg strength decreased in the vitamin D group but not in the placebo group (-2.6 pounds vs 1.8 pounds, P = .03). In women randomized to vitamin D, achieving repletion (25(OH)D ≥ 32 ng/mL) did not alter results. Vitamin D3 supplementation during weight-loss decreased leg strength but did not alter changes in lean mass or BMD in postmenopausal women with vitamin D insufficiency.

Vitamin D3 supplementation using an oral spray solution resolves deficiency but has no effect on VO2 max in Gaelic footballers: results from a randomised, double-blind, placebo-controlled trial

Purpose Vitamin D inadequacy is a global health concern in athletes as well as the general population. Whilst the role of vitamin D in skeletal health is well defined, there remains uncertainty over whether vitamin D supplementation has an added benefit beyond bone health.MethodsThis randomised placebo-controlled trial in healthy male and female Gaelic footballers (n = 42) investigated the effect of vitamin D3 supplementation [3000 IU (75 µg) daily for 12 weeks, via an oral spray solution] on VO2 max which was the primary outcome measure. Secondary outcomes included skeletal muscle and lung function.ResultsSupplementation significantly increased total 25-hydroxyvitamin D concentrations compared to the placebo group (mean ± SD change from baseline, 36.31 ± 32.34 vs. 6.11 ± 23.93 nmol/L, respectively; P = 0.006). At baseline, 50 and 22 % of footballers presented with vitamin D insufficiency (31–49 nmol/L) and deficiency (<30 nmol/L), respectively. Total 25-hydroxyvitamin D concentration did not significantly correlate with any measure of physical performance. Analysis of covariance (ANCOVA) models demonstrated that vitamin D supplementation over 12 weeks had no significant effect on VO2 max (P = 0.375), vertical jump height (P = 0.797), left and right handgrip strength (P = 0.146 and P = 0.266, respectively), forced vital capacity (P = 0.573) or forced expiratory volume at 1 s (P = 0.665), after adjusting for confounders. The high prevalence of vitamin D inadequacy observed in this cohort of collegiate Gaelic footballers supports the need for vitamin D supplementation during wintertime to avoid being at risk of poor bone health.ConclusionsTwelve-week daily supplementation with 3000 IU (75 µg) vitamin D3 successfully resolved deficiency but did not have any significant effect on VO2 max, skeletal muscle or lung function.

C–C motif ligand 11 reduction in CLL patients serum after vitamin D supplementation

Background: Vitamin D (VD) deficiency results in a worse prognosis in patients with chronic lymphocytic leukemia (CLL) and may affect the production of cytokines. Nonetheless, there is the lack of studies dealing with VD supplementation and its impact on chemokines in CLL patients.Aim: The primary endpoint of our interventional study was to evaluate the effect of cholecalciferol supplementation on serum chemokines levels in CLL patients.Materials and methods: Eighteen subjects with CLL were enrolled for the study. Six-month-long cholecalciferol supplementation was performed in CLL patients with serum 25-OH-D3 levels below 30 ng/ml. Cytokines levels were assessed at the beginning of the study and after 6 months. Baseline measurements of cytokines were compared to those in apparently healthy controls.Results: Increased levels of CCL2, CCL3, CCL4, CXCL8, CXCL10, TNFα, bFGF, G-CSF, and VEGF were found in CLL patients in comparison with the healthy controls. In the course of the VD supplementation a decrease in serum levels of chemokines CCL11, CCL3, and cytokine PDGF-BB was observed. The decrease of CCL11 was found in CLL patients on VD supplementation solely, whereas the decrease of CCL3 and PDGF-BB was observed in CLL subjects on both chemotherapy and VD supplementation.Conclusion: The VD supplementation may exert beneficial effect on chemokines levels in CLL patients with VD deficiency.

Vitamin D Supplementation Causes a Decrease in Blood Cholesterol in Professional Rowers.

In the skin vitamin D3 is synthesized from cholesterol, which leaves the question whether a feedback mechanism controlling the level of blood cholesterol exists. Here we investigate the effects of vitamin D3 supplementation on serum lipids in professional rowers. The rowers were divided into two groups following the same training schedule for 4 wk: one received placebo (TP) while the second received 5,000 IU of vitamin D3 every day (TD3). Plasma total antioxidant status, total triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL)-cholesterol (HDL-C), low-density lipoprotein (LDL)-cholesterol (LDL-C) and 25-hydroxyvitamin D (25-OH-D3) were determined in pre- and post-intervention. The ratios of TC/HDL-C and LDL-C/HDL-C were also calculated. Furthermore, maximal oxygen uptake was also measured at baseline. There were significant decreases over time in the TD3 group in TC 186±18 vs 163±21 (p<0.05) and HDL-C; LDL-C also decreased, but the changes were not statistically significant. Moreover, the supplementation caused a significant rise in blood 25-OH-D3 (+98%). Neither training nor vitamin D3 supplementation had an effect on total antioxidant status. In conclusion, the alterations in the lipoprotein profile seen in this study would suggest that effects of regular exercise on lipoprotein profile may linked to vitamin D3 status.

Effect of cholecalciferol supplementation on urine podocyte-associated messenger RNAs in patients with chronic kidney disease.

Vitamin D reduces albuminuria in patients with chronic kidney disease (CKD) but its effects on glomerular podocytes are not entirely understood. To evaluate if cholecalciferol supplementation reduces the levels of podocyte-associated urine mRNAs in patients with CKD. A total of 27 patients with stages 2 to 4 CKD and suboptimal serum vitamin D [25(OH)D] levels were treated with cholecalciferol for 6 months. Serum 25(OH)D level, estimated glomerular filtration rate (eGFR), proteinuria, and urine mRNA of nephrin, podocin, podocalyxin, transient receptor potential cation channel 6, vascular endothelial growth factor A, and transforming growth factor beta were assessed before and after intervention. eGFR declined at an average rate of -4.71 mL/min/1.73 m2 (p = 0.010 vs. baseline), being 28 ± 16 mL/min/1.73 m2 at six months. No changes in proteinuria or mineral and bone metabolism parameters were observed after cholecalciferol supplementation. Urinary podocyte-associated mRNAs did not change significantly after treatment. However, patients who achieved 25(OH)D level > 20 ng/mL at six months showed a trend of reduction of urinary nephrin and podocin mRNA levels; in patients with 25(OH)D that remained < 20 ng/mL there was a significant increase in urinary podocalyxin, and a trend of higher expression of urinary nephrin and podocin mRNA. Six months of cholecalciferol supplementation had no effect on urine podocyte-associated mRNA profile of patients with advanced CKD. The protective effect of vitamin D or its analogues on the glomerular podocyte should be investigated in early stages of CKD with a longer treatment period.

Effect of Vitamin-D supplementation on blood pressure in post-menopausal women: A community based interventional study

Effect of Vitamin-D supplementation on blood pressure in post-menopausal women: A community based interventional study