Randomized controlled trial of calcium supplementation in healthy, nonosteoporotic, older men

Arch Intern Med. 2008 Nov 10;168(20):2276-82. doi: 10.1001/archinte.168.20.2276.


Background: There is no consistent evidence, to our knowledge, that calcium supplementation affects bone mineral density (BMD) in men, despite male osteoporosis being a common clinical problem.

Methods: To determine the effects of calcium supplementation (600 mg/d, 1200 mg/d, or placebo) on BMD in men, we conducted a double-blind, randomized controlled trial for a 2-year period at an academic clinical research center. A total of 323 healthy men at least 40 years old (mean age, 57 years) were recruited by newspaper advertisement. Complete follow-up was achieved in 96% of subjects.

Results: The BMD increased at all sites in the group receiving calcium, 1200 mg/d, by 1% to 1.5% more than those receiving placebo. The results for the group receiving calcium, 600 mg/d, were not different from the placebo group at any BMD site. There was no interaction between the BMD treatment effect and either age or dietary calcium intake. There were dosage-related, sustained decreases in serum parathyroid hormone (P < .001), total alkaline phosphatase activity (P = .01), and procollagen type 1 N-terminal propeptide (P < .001) amounting to 25%, 8%, and 20%, respectively, in the group receiving calcium, 1200 mg/d, at 2 years. Tooth loss, constipation, and cramps were unaffected by calcium supplementation, falls tended to be less frequent in the group receiving calcium, 1200 mg/d, but vascular events tended to be more common in the groups receiving calcium vs the group receiving placebo.

Conclusion: Calcium, 1200 mg/d, has effects on BMD in men comparable with those found in postmenopausal women but a dosage of 600 mg/d is ineffective for treating BMD.

Trial registration: actr.org.au Identifier: 012605000274673.

Publication types

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

MeSH terms

  • Accidental Falls
  • Aged
  • Alkaline Phosphatase / blood
  • Bone Density / drug effects*
  • Calcium Citrate / administration & dosage
  • Calcium, Dietary / pharmacology*
  • Constipation
  • Dietary Supplements*
  • Double-Blind Method
  • Follow-Up Studies
  • Fractures, Bone
  • Humans
  • Male
  • Medication Adherence
  • Middle Aged
  • Muscle Cramp
  • Parathyroid Hormone / blood
  • Peptide Fragments / blood
  • Procollagen / blood
  • Tooth Loss
  • Vascular Diseases / chemically induced


  • Calcium, Dietary
  • Parathyroid Hormone
  • Peptide Fragments
  • Procollagen
  • procollagen Type I N-terminal peptide
  • Alkaline Phosphatase
  • Calcium Citrate