Effects of Calcium-Vitamin D Co-Supplementation on Glycaemic Control, Inflammation and Oxidative Stress in Gestational Diabetes: A Randomised Placebo-Controlled Trial

Diabetologia. 2014 Sep;57(9):1798-806. doi: 10.1007/s00125-014-3293-x. Epub 2014 Jun 25.

Abstract

Aims/hypothesis: This study was designed to assess the effects of calcium and vitamin D supplementation on the metabolic status of pregnant women with gestational diabetes mellitus (GDM).

Methods: This randomised placebo-controlled trial was performed at maternity clinics affiliated to Kashan University of Medical Sciences, Kashan, Iran. Participants were 56 women with GDM at 24-28 weeks' gestation (18 to 40 years of age). Subjects were randomly assigned to receive calcium plus vitamin D supplements or placebo. All study participants were blinded to group assignment. Individuals in the calcium-vitamin D group (n = 28) received 1,000 mg calcium per day and a 50,000 U vitamin D3 pearl twice during the study (at study baseline and on day 21 of the intervention), and those in the placebo group (n = 28) received two placebos at the mentioned times. Fasting blood samples were taken at study baseline and after 6 weeks of intervention.

Results: The study was completed by 51 participants (calcium-vitamin D n = 25, placebo n = 26). However, as the analysis was based on an intention-to-treat approach, all 56 women with GDM (28 in each group) were included in the final analysis. After the administration of calcium plus vitamin D supplements, we observed a significant reduction in fasting plasma glucose (-0.89 ± 0.69 vs +0.26 ± 0.92 mmol/l, p < 0.001), serum insulin levels (-13.55 ± 35.25 vs +9.17 ± 38.50 pmol/l, p = 0.02) and HOMA-IR (-0.91 ± 1.18 vs +0.63 ± 2.01, p = 0.001) and a significant increase in QUICKI (+0.02 ± 0.03 vs -0.002 ± 0.02, p = 0.003) compared with placebo. In addition, a significant reduction in serum LDL-cholesterol (-0.23 ± 0.79 vs +0.26 ± 0.74 mmol/l, p = 0.02) and total cholesterol: HDL-cholesterol ratio (-0.49 ± 1.09 vs +0.18 ± 0.37, p = 0.003) and a significant elevation in HDL-cholesterol levels (+0.15 ± 0.25 vs -0.02 ± 0.24 mmol/l, p = 0.01) was seen after intervention in the calcium-vitamin D group compared with placebo. In addition, calcium plus vitamin D supplementation resulted in a significant increase in GSH (+51.14 ± 131.64 vs -47.27 ± 203.63 μmol/l, p = 0.03) and prevented a rise in MDA levels (+0.06 ± 0.66 vs +0.93 ± 2.00 μmol/l, p = 0.03) compared with placebo.

Conclusions/interpretation: Calcium plus vitamin D supplementation in women with GDM had beneficial effects on their metabolic profile.

Trial registration: www.irct.ir IRCT201311205623N11.

Funding: The study was supported by a grant (no. 92110) from Kashan University of Medical Sciences.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Blood Glucose / drug effects
  • Calcium / administration & dosage
  • Calcium / therapeutic use*
  • Diabetes, Gestational / drug therapy*
  • Dietary Supplements
  • Female
  • Humans
  • Inflammation / metabolism*
  • Oxidative Stress / drug effects*
  • Pregnancy
  • Vitamin D / blood
  • Vitamin D / therapeutic use*
  • Young Adult

Substances

  • Blood Glucose
  • Vitamin D
  • Calcium

Associated data

  • IRCT/IRCT201311205623N11