Calcium-vitamin D cosupplementation influences circulating inflammatory biomarkers and adipocytokines in vitamin D-insufficient diabetics: A randomized controlled clinical trial

Abstract

Context: To the best of our knowledge, no study has examined the effects of vitamin D-calcium cosupplementation on inflammatory biomarkers and adipocytokines in vitamin D-insufficient type 2 diabetics. Objective: This study was performed to assess the effects of vitamin D and calcium supplementation on inflammatory biomarkers and adipocytokines in vitamin D-insufficient people with type 2 diabetes. Methods: Totally, 118 diabetic patients were enrolled in this randomized, placebo-controlled clinical trial. After matching for age, sex, body mass index, type and dose of hypoglycemic agents, and duration of diabetes, subjects were randomly assigned into 4 groups receiving the following: 1) 50000 IU/wk vitamin D + calcium placebo; 2) 1000 mg/d calcium + vitamin D placebo; 3) 50 000 IU/wk vitamin D + 1000 mg/d calcium; or 4) vitamin D placebo + calcium placebo for 8 weeks. Blood sampling was done for the quantification of inflammatory biomarkers and adipocytokines at the study baseline and after 8 weeks of intervention. Results: Calcium (changes from baseline: -75±19 ng/ml, P = .01) and vitamin D alone (-56 ± 19 ng/mL, P = .01) and joint calcium-vitamin D supplementation (-92 ± 19 ng/mL, P = .01) resulted in a significant reduction in serum leptin levels compared with placebo (-9 ± 18 ng/mL). This was also the case for serum IL-6, such that calcium (-2 ± 1 pg/mL, P < .05), vitamin D (-3.1 ± 1.3, P < .05), and joint calcium-vitamin D groups (-3.4 ± 1.3, P