Relationship between vitamin D, parathyroid hormone, and bone health

J Clin Endocrinol Metab. 2011 Mar;96(3):E436-46. doi: 10.1210/jc.2010-1886. Epub 2010 Dec 15.


Context: There is a controversy regarding the definition of vitamin D insufficiency as it relates to bone health.

Objective: The objective of the study was to examine the evidence for a threshold value of serum 25-hydroxyvitamin D (25OHD) that defines vitamin D insufficiency as it relates to bone health.

Design and participants: This was a cross-sectional analysis of baseline data in 488 elderly Caucasian women, mean age 71 yr, combined with a literature review of 70 studies on the relationship of serum PTH to serum 25OHD.

Setting: The study was conducted in independent-living women in the midwest United States.

Main outcome measure: The relationship between serum 25OHD, serum PTH, and serum osteocalcin and 24-h urine N-telopeptides was evaluated.

Results: Serum PTH was inversely correlated with serum 25OHD (r = -0.256, P < 0.0005), but no threshold as defined by suppression of serum PTH was found within the serum 25OHD range 6-60 ng/ml (15-150 nmol/liter). However, in contrast, there was a threshold for bone markers, serum osteocalcin and urine N-telopeptides, that increased only below a serum 25OHD of approximately 18 ng/ml (45 nmol/liter). Calcium absorption was not correlated with serum PTH and serum 25OHD, and no threshold was found. A literature review of 70 studies generally showed a threshold for serum PTH with increasing serum 25OHD, but there was no consistency in the threshold level of serum 25OHD that varied from 10 to 50 ng/ml (25-125 nmol/liter).

Conclusions: Vitamin D insufficiency should be defined as serum 25OHD less than 20 ng/ml (50 nmol/liter) as it relates to bone.

Publication types

  • Meta-Analysis
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Aging / physiology
  • Biomarkers
  • Bone and Bones / physiology*
  • Calcium / metabolism
  • Cross-Sectional Studies
  • Female
  • Geography
  • Health
  • Humans
  • Hydroxycholecalciferols / blood
  • Linear Models
  • Male
  • Nutritional Status / physiology*
  • Osteocalcin / blood
  • Parathyroid Hormone / physiology*
  • Reference Standards
  • Sex Characteristics
  • United States
  • Vitamin D / physiology*
  • Vitamin D Deficiency / blood*
  • Vitamin D Deficiency / diagnosis


  • Biomarkers
  • Hydroxycholecalciferols
  • Parathyroid Hormone
  • Osteocalcin
  • Vitamin D
  • Calcium