Micronutrients & recovery
In postmenopausal women with vitamin D insufficiency, a daily vitamin D3 dose of 800 IU (with adequate calcium) raises serum 25-hydroxyvitamin D levels above 50 nmol/L in 97.5% of the population, meeting the Recommended Dietary Allowance (RDA).
If you are a postmenopausal woman with low vitamin D levels, taking 800 IU of Vitamin D3 daily along with adequate calcium (1200-1400 mg total) will raise your blood levels above the recommended threshold for nearly everyone in your demographic. You do not need extremely high doses; levels plateau around 3200 IU, making 800 IU the efficient target.
A vitamin D3 dosage of 800 IU/d increased serum 25-(OH)D levels to greater than 50 nmol/L in 97.5% of women; however, a model predicted the same response with a vitamin D3 dosage of 600 IU/d.
Why this rating
Randomized, placebo-controlled trial with high adherence (94%) and rigorous statistical modeling, though limited to white postmenopausal women.
Source
Dose Response to Vitamin D Supplementation in Postmenopausal Women
John C. Gallagher et al. · Annals of Internal Medicine · 2012
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