Bischoff-Ferrari, Heike A.Shao, AndrewDawson-Hughes, BessHathcock, JohnGiovannucci, EdwardWillett, Walter2019-09-232010Bischoff-Ferrari, H. A., A. Shao, B. Dawson-Hughes, J. Hathcock, E. Giovannucci, and W. C. Willett. 2009. “Benefit–risk Assessment of Vitamin D Supplementation.” Osteoporosis International 21 (7): 1121–32. https://doi.org/10.1007/s00198-009-1119-3.0937-941X1433-2965http://nrs.harvard.edu/urn-3:HUL.InstRepos:41392095Current intake recommendations of 200 to 600 IU vitamin D per day may be insufficient for important disease outcomes reduced by vitamin D.This study assessed the benefit of higher-dose and higher achieved 25-hydroxyvitamin D levels [25(OH)D] versus any associated risk.Based on double-blind randomized control trials (RCTs), eight for falls (n = 2426) and 12 for non-vertebral fractures (n = 42,279), there was a significant dose-response relationship between higher-dose and higher achieved 25(OH)D and greater fall and fracture prevention. Optimal benefits were observed at the highest dose tested to date for 700 to 1000 IU vitamin D per day or mean 25(OH)D between 75 and 110 nmol/l (30-44 ng/ml). Prospective cohort data on cardiovascular health and colorectal cancer prevention suggested increased benefits with the highest categories of 25(OH)D evaluated (median between 75 and 110 nmol/l). In 25 RCTs, mean serum calcium levels were not related to oral vitamin D up to 100,000 IU per day or achieved 25(OH)D up to 643 nmol/l. Mean levels of 75 to 110 nmol/l were reached in most RCTs with 1,800 to 4,000 IU vitamin D per day without risk.Our analysis suggests that mean serum 25(OH)D levels of about 75 to 110 nmol/l provide optimal benefits for all investigated endpoints without increasing health risks. These levels can be best obtained with oral doses in the range of 1,800 to 4,000 IU vitamin D per day; further work is needed, including subject and environment factors, to better define the doses that will achieve optimal blood levels in the large majority of the population.en-USJournal Article2019-09-2310.1007/s00198-009-1119-3