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Word of the Day

Vitamin D supplementation does not improve mental well-being

Clinical Question:
Does an annual dose of vitamin D improve feelings of well-being in older women?

Bottom Line:
Annual vitamin D supplementation does not increase feelings of well-being, at least among older women. (LOE = 1b)

Sanders KM, Stuart AL, Williamson EJ, et al. Annual high-dose vitamin D3 and mental well-being: randomised controlled trial. Br J Psychiatry 2011;198(5):357-364.  [PMID:21525520]

Study Design:
Randomized controlled trial (double-blinded)




The Australian researchers conducting this study recruited 2317 community-dwelling women 70 years and older. The women were randomized, allocation concealment uncertain, to receive a single yearly dose of 500,000 IU vitamin D3 or placebo every autumn/winter for 3 to 5 consecutive years. Well-being was assessed using 4 different surveys of mental well-being, completed at baseline and immediately before and 3 months after the second dose. Using intention-to-treat analysis, there were no significant differences between the vitamin D group and placebo group despite a 41% higher vitamin D level in the treatment group. The study had an 80% power to find at least a 50% difference in responses, if one existed.


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