TY - JOUR
T1 - Serum 25-Hydroxyvitamin D Levels
T2 - Variability, Knowledge Gaps, and the Concept of a Desirable Range
AU - El-Hajj Fuleihan, Ghada
AU - Bouillon, Roger
AU - Clarke, Bart
AU - Chakhtoura, Marlene
AU - Cooper, Cyrus
AU - McClung, Michael
AU - Singh, Ravinder J.
N1 - Publisher Copyright:
© 2015 American Society for Bone and Mineral Research. © 2015 American Society for Bone and Mineral Research.
PY - 2015/7/1
Y1 - 2015/7/1
N2 - Hypovitaminosis D is prevalent worldwide but proportions vary widely between regions, depending on genetic and lifestyle factors, the threshold to define deficiency, and accuracy of 25-hydroxyvitamin D (25OHD) assays used. Latitude, pollution, concealing clothing, sun exposure, gender, dietary habits, and lack of government regulation account for up to 50% in variations in serum 25OHD levels, whereas genetic polymorphisms in the vitamin D pathway account for less than 5%. Organizations/societies have developed guidelines for recommended desirable 25OHD levels and vitamin D doses to reach them, but their applicability across age groups and populations are still debated. This article and the accompanying online Supporting Information highlight sources of variations in circulating 25OHD levels, uncertainties and knowledge gaps, and analytical problems facing 25OHD assays, while keeping efficacy and safety data as the dominant factors when defining a desirable range for 25OHD levels. We propose a desirable range of 20 to 40ng/mL (50 to 100nmol/L), provided precise and accurate assays are used. Although slightly lower levels, 15 to 20ng/mL, may be sufficient for some infants and adults, higher levels, 40 to 60ng/mL, may still be safe. This desirable range allows physicians to tailor treatment while taking season, lifestyle, vitamin D intake, and other sources of variation into account. We reserve 25OHD measurements for at-risk patients, defined by disease or lifestyle, and the use of 25OHD assays calibrated against the recommended international standards. Most target groups reach desirable target levels by a daily intake of 400 to 600IU for children and 800IU for adults. A total daily allowance of vitamin D of up to 1000IU in the pediatric age groups, and up to 2000IU in adults, tailored to an individual patient risk profile, is probably safe over long durations. Additional data are needed to validate the proposed range and vitamin D doses, especially in children, pregnant women, and non-white populations.
AB - Hypovitaminosis D is prevalent worldwide but proportions vary widely between regions, depending on genetic and lifestyle factors, the threshold to define deficiency, and accuracy of 25-hydroxyvitamin D (25OHD) assays used. Latitude, pollution, concealing clothing, sun exposure, gender, dietary habits, and lack of government regulation account for up to 50% in variations in serum 25OHD levels, whereas genetic polymorphisms in the vitamin D pathway account for less than 5%. Organizations/societies have developed guidelines for recommended desirable 25OHD levels and vitamin D doses to reach them, but their applicability across age groups and populations are still debated. This article and the accompanying online Supporting Information highlight sources of variations in circulating 25OHD levels, uncertainties and knowledge gaps, and analytical problems facing 25OHD assays, while keeping efficacy and safety data as the dominant factors when defining a desirable range for 25OHD levels. We propose a desirable range of 20 to 40ng/mL (50 to 100nmol/L), provided precise and accurate assays are used. Although slightly lower levels, 15 to 20ng/mL, may be sufficient for some infants and adults, higher levels, 40 to 60ng/mL, may still be safe. This desirable range allows physicians to tailor treatment while taking season, lifestyle, vitamin D intake, and other sources of variation into account. We reserve 25OHD measurements for at-risk patients, defined by disease or lifestyle, and the use of 25OHD assays calibrated against the recommended international standards. Most target groups reach desirable target levels by a daily intake of 400 to 600IU for children and 800IU for adults. A total daily allowance of vitamin D of up to 1000IU in the pediatric age groups, and up to 2000IU in adults, tailored to an individual patient risk profile, is probably safe over long durations. Additional data are needed to validate the proposed range and vitamin D doses, especially in children, pregnant women, and non-white populations.
KW - DESIRABLE RANGE
KW - EFFICACY
KW - ETHNICITIES
KW - KNOWLEDGE GAPS
KW - SAFETY
KW - VARIATIONS
KW - VITAMIN D
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U2 - 10.1002/jbmr.2536
DO - 10.1002/jbmr.2536
M3 - Review article
C2 - 25952470
AN - SCOPUS:84931957121
SN - 0884-0431
VL - 30
SP - 1119
EP - 1133
JO - Journal of Bone and Mineral Research
JF - Journal of Bone and Mineral Research
IS - 7
ER -