1.
Vitamin D Supplementation Improves Fasting Insulin Levels and HDL Cholesterol in Infertile Men.
Holt, R, Petersen, JH, Dinsdale, E, Knop, FK, Juul, A, Jørgensen, N, Blomberg Jensen, M
The Journal of clinical endocrinology and metabolism. 2022;(1):98-108
Abstract
CONTEXT Vitamin D has been linked with glucose and lipid metabolism. Men with impaired gonadal function have a higher risk of metabolic syndrome and mortality, and vitamin D status may be a reversible modulator. OBJECTIVE This work aimed to determine the effect of daily vitamin D and calcium supplementation for 150 days on glucose and lipid homeostasis in infertile men. METHODS A single-center, double-blinded, randomized clinical trial (NCT01304927) was conducted. A total of 307 infertile men were randomly assigned (1:1) to a single dose of 300 000 IU cholecalciferol followed by 1400 IU cholecalciferol + 500 mg of calcium daily (n = 151) or placebo (n = 156) for 150 days. Reported metabolic parameters including fasting plasma glucose, glycated hemoglobin A1c, fasting serum insulin, homeostatic model assessment of insulin resistance (HOMA-IR), fasting plasma cholesterols, and triglycerides were secondary end points. The primary end point semen quality has previously been reported. RESULTS Men receiving vitamin D supplementation improved their vitamin D status, whereas vitamin D status was aggravated in the placebo group characterized by higher serum parathyroid hormone. At the end of the trial, men receiving vitamin D supplementation had 13% lower fasting serum insulin concentrations compared with the placebo-treated group (65 vs 74 pmol/L, P = .018) and 19% lower HOMA-IR (2.2 vs 2.7, P = .025). Moreover, men in the vitamin D group had higher high-density lipoprotein (HDL) cholesterol levels (1.38 vs 1.32 mmol/L, P = .008) compared with the placebo group. CONCLUSION High-dose vitamin D supplementation has beneficial effects on glucose homeostasis and HDL cholesterol levels in infertile men.
2.
High Dose Supplementation of Vitamin D Affects Measures of Systemic Inflammation: Reductions in High Sensitivity C-Reactive Protein Level and Neutrophil to Lymphocyte Ratio (NLR) Distribution.
Tabatabaeizadeh, SA, Avan, A, Bahrami, A, Khodashenas, E, Esmaeili, H, Ferns, GA, Abdizadeh, MF, Ghayour-Mobarhan, M
Journal of cellular biochemistry. 2017;(12):4317-4322
Abstract
The prevalence of Vitamin D deficiency is increasing worldwide, which has be shown to be associated with increased risk of cardiovascular disease (CVD), autoimmune disease, and metabolic syndrome. These conditions are also associated with a heightened state of inflammation. The aim of the current study was to evaluate the effect of vitamin D supplementation on serum C-Reactive Protein (CRP) level and Neutrophil-to-lymphocyte ratio (NLR) distribution in a large cohort of adolescent girls. A total of 580 adolescent girls were recruited follow by evaluation of CRP and hematological parameters before and after supplementation with vitamin D supplements as 9 of 50000 IU cholecalciferol capsules for 9 weeks taken at weekly intervals. At baseline, serum hs-CRP level was 0.9 (95%CI: 0.5-1.8), while this value after intervention was reduced to 0.8 (95%CI: 0.3-1.6; P = 0.007). Similar results were also detected for NLR (e.g., NLR level was 1.66 ± 0.72 and 1.53 ± 0.67, P = 0.002, before and after therapy with compliance rate of >95.2%). Moreover, we found an association between hs-CRP and BMI, triglyceride, white blood cell count, and lymphocytes. Interestingly we observed a significant reduction in neutrophil count and CRP level after high dose vitamin D supplementation. Our findings showed that the high dose supplementation of vitamin D affects measures of systemic inflammation: reductions in High Sensitivity C-Reactive Protein level and Neutrophil-to-lymphocyte ratio (NLR) distribution. J. Cell. Biochem. 118: 4317-4322, 2017. © 2017 Wiley Periodicals, Inc.