Low vitamin D status: definition, prevalence, consequences, and correction.
Vitamin D is obtained from cutaneous production when 7-dehydrocholesterol is converted to vitamin D(3) (cholecalciferol) by ultraviolet B radiation or by oral intake of vitamin D(2) (ergocalciferol) and D(3). An individual's vitamin D status is best evaluated by measuring the circulating 25-hydroxyvitamin D (25(OH)D) concentration. Although controversy surrounds the definition of low vitamin D status, there is increasing agreement that the optimal circulating 25(OH)D level should be approximately 30 to 32 ng/mL or above. Using this definition, it has been estimated that approximately three-quarters of all adults in the United States have low levels. Low vitamin D status classically has skeletal consequences such as osteomalacia/rickets. More recently, associations between low vitamin D status and increased risk for various nonskeletal morbidities have been recognized; whether all of these associations are causally related to low vitamin D status remains to be determined. To achieve optimal vitamin D status, daily intakes of at least 1000 IU or more of vitamin D are required. The risk of toxicity with "high" amounts of vitamin D intake is low. Substantial between-individual variability exists in response to the same administered vitamin D dose. When to monitor 25(OH)D levels has received little attention. Supplementation with vitamin D(3) may be preferable to vitamin D(2).
Binkley
Neil
N
University of Wisconsin-Madison Osteoporosis Clinical Center and Research Program, Madison, WI 53705, USA. nbinkley@wisc.edu
Ramamurthy
Rekha
R
Krueger
Diane
D
D001842:Bone and Bones / Q000378:metabolism; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D009132:Muscles / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism; D009751:Nutritional Requirements; D010018:Osteomalacia / Q000178:diet therapy; D015995:Prevalence; D012279:Rickets / Q000178:diet therapy; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism / Q000627:therapeutic use / Q000633:toxicity; D014808:Vitamin D Deficiency / Q000097:blood / Q000178:diet therapy / Q000453:epidemiology / Q000378:metabolism
D014807:Vitamin D; C104450:25-hydroxyvitamin D