Calcium intake in winter pregnancy attenuates impact of vitamin D inadequacy on urine NTX, a marker of bone resorption
European Journal of Nutrition, pp 1–9, First Online: 21 February 2017
DOI: 10.1007/s00394-017-1385-3
Eileen C. O’Brien, Mark T. Kilbane, Malachi J. McKenna, Ricardo Segurado, Aisling A. Geraghty, Fionnuala M. McAuliffe
- Vitamin D Cofactors in a nutshell
- Why Most Calcium Supplement Recommendations are DEAD WRONG - Sept 2013
- Off Topic: More than 800 mg of Calcium increases risk of Macular Degeneration in seniors by 2.6X – JAMA April 2015
- More Calcium absorbed with more vitamin D – 6.7% more with 4000 IU – RCT March 2014
Items in both categories Pregnancy and Calcium are listed here:
- Mild acidic diet with vitamin D eliminated hypocalcemia before birth (cows) – Dec 2017
- Preeclampsia reduced 2X by Vitamin D, by 5X if also add Calcium – meta-analysis Oct 2017
- Pregnancies in the winter lacking vitamin D need more Calcium – Feb 2017
- Bones better after pregnancy with just 200 IU of vitamin D plus 600 Calcium – RCT July 2013
- Calcium and bone disorders in pregnancy – May 2012
Purpose
Pregnancy is characterised by increased bone turnover, but high bone turnover with resorption exceeding formation may lead to negative maternal bone remodelling. Recent studies are conflicting regarding the effect of calcium on skeletal health in pregnancy. The aim of this study was to examine the seasonal effect of serum 25-hydroxyvitamin D (25OHD) and dietary calcium on a marker of bone resorption.
Methods
This was prospective study of 205 pregnant women two cohorts; early pregnancy at 13 weeks (n = 96), and late pregnancy at 28 weeks (n = 109). Serum 25OHD and urine cross-linked N-telopeptides of type I collagen (uNTX) were measured at both time points. Intakes of vitamin D and calcium were recorded using 3-day food diaries at each trimester.
Results
Compared to summer pregnancies, winter pregnancies had significantly lower 25OHD and significantly higher uNTX. Higher calcium intakes were negatively correlated with uNTX in winter, but not summer. In late pregnancy, compared to those reporting calcium intakes ≥1000 mg/day, intakes of <1000 mg/day were associated with a greater increase in uNTX in winter pregnancies than in summer (41.8 vs. 0.9%). Increasing calcium intake in winter by 200 mg/day predicted a 13.3% reduction in late pregnancy uNTX.
Conclusions
In late pregnancy, during winter months when 25OHD is inadequate, intakes of dietary calcium <1000 mg/day were associated with significantly increased bone resorption (uNTX). Additional dietary calcium is associated with reduced bone resorption in late pregnancy, with greater effect observed in winter. Further research regarding optimal dietary calcium and 25OHD in pregnancy is required, particularly for women gestating through winter.
References are on-line