Calcium and vitamin d supplementation in postmenopausal women

J Clin Endocrinol Metab. 2013 Nov;98(11):E1702-9. doi: 10.1210/jc.2013-2121. Epub 2013 Sep 24.


Context: Bone health is influenced by the intake of both calcium and vitamin D.

Objective: Our objective was to evaluate the influence of calcium and vitamin D supplementation on PTH and bone turnover. SETTING, PATIENTS, AND DESIGN: At an ambulatory research center, 159 postmenopausal healthy white women participated in this double-blind, placebo-controlled parallel, longitudinal factorial study that was 6 months in duration.

Interventions: Subjects were randomly allocated to 4 groups: 1) double placebo, 2) calcium (1200 mg daily) plus placebo, 3) vitamin D3 (100 μg) plus placebo, and 4) vitamin D3 and calcium. Serum and urine were collected fasting and 2 hours after a calcium load at baseline and at 3 and 6 months.

Main outcome measures: Serum PTH, cross-linked C-telopeptide (CTX), and procollagen type I N-terminal propeptide (P1NP) were measured.

Results: Before study medication, a calcium load resulted in a decline in PTH and CTX and an increase in urinary calcium excretion. Serum CTX and P1NP declined over time with calcium supplementation but did not change with increased vitamin D intake. There was a decline in PTH in the vitamin D groups in the fasting state compared with placebo. Suppression of PTH was greater after a calcium load in the vitamin D groups. A calcium load decreased PTH and CTX and raised urinary calcium.

Conclusions: Fasting PTH declines with vitamin D supplementation. PTH declines after calcium intake. Supplementation of the diet with 1200 mg calcium/d reduces bone turnover markers, whereas supplementation with up to100 μg vitamin D3/d does not.

Trial registration: NCT00762775.

Publication types

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

MeSH terms

  • Aged
  • Bone Remodeling / drug effects*
  • Bone and Bones / drug effects*
  • Bone and Bones / metabolism
  • Calcium / urine
  • Calcium, Dietary / administration & dosage*
  • Calcium, Dietary / adverse effects
  • Cholecalciferol / administration & dosage*
  • Cholecalciferol / adverse effects
  • Collagen Type I / blood
  • Dietary Supplements
  • Female
  • Fractures, Bone / prevention & control
  • Humans
  • Longitudinal Studies
  • Middle Aged
  • Osteomalacia / prevention & control
  • Osteoporosis / prevention & control*
  • Parathyroid Hormone / blood
  • Peptide Fragments / blood
  • Peptides / blood
  • Placebos
  • Postmenopause / drug effects*
  • Procollagen / blood
  • Vitamins / administration & dosage
  • Vitamins / adverse effects


  • Calcium, Dietary
  • Collagen Type I
  • Parathyroid Hormone
  • Peptide Fragments
  • Peptides
  • Placebos
  • Procollagen
  • Vitamins
  • collagen type I trimeric cross-linked peptide
  • procollagen type I carboxy terminal peptide
  • Cholecalciferol
  • Calcium

Associated data