Dietary requirement for Vitamin D for older people, trial
PainSci summary of Cashman 2009?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★★★★☆?4-star ratings are for bigger/better studies and reviews published in more prestigious journals, with only quibbles. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.
There’s limited evidence for how much vitamin D older adults need in their diet. This study was a test of over 200 men and women over the age of 64. It found that the vast majority of adults need 320-2000 IU per day during the winter, depending how much sun they got in the summer. This paper does not discuss the safe upper limits of supplementation dosages.
original abstract†Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
BACKGROUND: Older adults may be more prone to developing vitamin D deficiency than younger adults. Dietary requirements for vitamin D in older adults are based on limited evidence.
OBJECTIVE: The objective was to establish the dietary intake of vitamin D required to maintain serum 25-hydroxyvitamin D [25(OH)D] concentrations above various cutoffs between 25 and 80 nmol/L during wintertime, which accounted for the effect of summer sunshine exposure and diet.
DESIGN: A randomized, placebo-controlled, double-blind, 22-wk intervention was conducted in men and women aged >/=64 y (n = 225) at supplemental levels of 0, 5, 10, and 15 microg vitamin D(3)/d from October 2007 to March 2008.
RESULTS: Clear dose-related increments (P < 0.0001) in serum 25(OH)D were observed with increasing supplemental vitamin D(3) intakes. The slope of the relation between total vitamin D intake and serum 25(OH)D was 1.97 nmol . L(-1) . microg intake(-1). The vitamin D intake that maintained serum 25(OH)D concentrations>25 nmol/L in 97.5% of the sample was 8.6 microg/d. Intakes were 7.9 and 11.4 microg/d in those who reported a minimum of 15 min daily summer sunshine exposure or less, respectively. The intakes required to maintain serum 25(OH)D concentrations of>37.5,>50, and>80 nmol/L in 97.5\% of the sample were 17.2, 24.7, and 38.7 microg/d, respectively.
CONCLUSION: To ensure that the vitamin D requirement is met by the vast majority >97.5%) of adults aged >/=64 y during winter, between 7.9 and 42.8 microg vitamin D/d is required, depending on summer sun exposure and the threshold of adequacy of 25(OH)D.
related content
One article on PainScience.com cites Cashman 2009 as a source:
- PS Vitamin D for Pain — Is it safe and reasonable for chronic pain patients to take higher doses of Vitamin D? And just how high is safe?
