High Vitamin D Supplementation Preserves Bone Health in Postmenopausal Women

by | Jan 9, 2014 | 2013, Menopause, Vitamin D - Bone Health, Women's Health, Women's Health - Bone Health

Written by Greg Arnold DC, CSCS. In a study of 265 postmenopausal women, the group which did not take a vitamin D supplement had 12 times the loss in bone mineral density compared to the group that took 1000 IU a day.  

Of the many changes that women undergo during and after menopause, including hot flashes, night sweats, and mood changes (1), a serious but possibly preventable health issue is osteoporosis. Osteoporosis-related fractures result in 31,000 deaths each year (2), and every 10% decrease in bone density triples the risk of having an osteoporosis-related fracture. (3)

Now a new study (4) suggests high levels of vitamin D supplementation may help preserve bone health in postmenopausal women. The study included 265 healthy Caucasian women between the ages of 60 and 70 not suffering from any illness, having normal blood pressure (less than 140/90 mmHg) and not taking any medications. They were divided into 3 groups and given either 400 IU of vitamin D, 1000 IU of vitamin D, or placebo per day for one year. Every 2 months, they provided information on their diet, gave blood samples and had bone mineral density tests done until they completed the supplementation period. They then had one final visit one month after supplementation ended to measure their vitamin D levels.

By the end of the supplementation period, vitamin D levels in the 1000 IU per day group increased by 129% (33.2 to 75.9 nanomoles/Liter) compared to a 94% increase in the 400 IU per day (33.4 to 65.0 nmol/L) and a 10.7% decrease in the placebo group (35.8 to 32.0 nmol/L) (p < 0.05). When looking at bone mineral density, only those in the 1000 IU per day saw a benefit, suffering only a 0.05% loss in bone mineral density (0.923 to 0.922 grams/centimeter2) while the 400 IU per day group saw a 0.57% loss in density (0.917 to 0.912 g/cm2) and the placebo group saw a 0.60% decrease (0.920 to 0.914 g/cm2) (p < 0.05).

One month after supplementation ended, the researchers noted that none of the patients who were in the 400 IU and 1000 IU per day groups were below 25 nmol/L compared to 40% of the placebo group. What’s more, only 16% of the 1000 IU per day group were below the 50 nmol/L levels recommended by the Institute of Medicine (5) compared to 50% in the 400 IU per day group and 94% of those in the placebo group.

For the researchers, “we found a small effect of vitamin D on BMD change in healthy postmenopausal women more than 5 years past menopause, in which 1000 IU but not 400 IU vitamin D appeared to attenuate bone loss over 1 year.”

Source: Macdonald, Helen M., et al. “Hip bone loss is attenuated with 1000 IU but not 400 IU daily vitamin D3: A 1‐year double‐blind RCT in postmenopausal women.” Journal of Bone and Mineral Research 28.10 (2013): 2202-2213.

© 2013 American Society for Bone and Mineral Research

 Posted January 9, 2014.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com

References:

  1. “Menopause” posted on the NIH website.
  2. Cooper C, Atkinson EJ, Jacobsen SJ, O’Fallon WM, Melton LJ 3d. Population-based study of survival after osteoporotic fractures. Am J Epidemiol 1993; 137:1001-5.
  3. Bone density measurement–a systematic review. J Intern Med 1997;241(suppl 739):1-60.
  4. Macdonald HM.  Hip bone loss is attenuated with 1000 IU but not 400 IU daily vitamin D3: a 1-year double-blind RCT in postmenopausal women.  J Bone Miner Res.2013 Oct;28(10):2202-13. doi: 10.1002/jbmr.1959.
  5. IOM (Institute of Medicine). Dietary reference intakes for calcium and vitamin D. Washington, DC: The National Academies Press; 2011.