Inclusion of 95 % range in the model to account for inter-individual variability increased the predicted intake of vitamin D needed to maintain serum 25(OH)D ≥ 50 nmol/l to 930 IU/d .
Vitamin D3 and vitamin K1 supplementation of Dutch postmenopausal women with normal and low bone mineral densities: effects on serum 25-hydroxyvitamin D and carboxylated osteocalcin
Objective : Improvement of vitamin D and K status of about 60 -y-old postmenopausal Dutch women . Design : In a r and omized study postmenopausal women with normal ( T-score > −1 ; n=96 ) and low ( T-score≤−1 ; n=45 ) bone mineral density ( BMD ) of the lumbar spine , were supplemented with 350–400 IU vitamin D3 , 80 μg vitamins K1 , vitamins K1+D3 , or placebo for 1 y. Serum 25-hydroxyvitamin D [ 25(OH)D ] and percentage carboxylated osteocalcin ( % carbOC ) were measured at baseline and after 3 , 6 and 12 months . Results : Baseline % carbOC of the entire study population was positively correlated with BMD of the lumbar spine and femoral neck . Correspondingly , women with low BMD had lower % carbOC at baseline than women with normal BMD but this difference disappeared after 1 y of supplementation with vitamin K1 ( ( mean±s.d . ) 68±11 % ( 95 % CI , 64.5–71.2 % ) vs 72±6 % ( 95 % CI , 70.1–72.9 % ) , respectively ) . One year of supplementation with vitamin D3 showed maximum increases in 25(OH)D of 33±29 % ( 95 % CI , 24.8–41.8 % ) and 68±58 % ( 95 % CI , 50.1–84.6 % ) in women with normal and low BMD , respectively . During winter , however , a 29 % decline in maximum 25(OH)D levels was not prevented in women with low BMD . Conclusion : Daily supplementation of Dutch postmenopausal women with > 400 IU vitamin D3 is indicated to prevent a winter decline in 25(OH)D and to control serum parathyroid hormone levels . Daily supplementation with 80 μg vitamin K1 seems to be necessary to reach premenopausal % carbOC levels . A stimulatory effect of calcium and /or vitamin D on % carbOC can not be excluded . European Journal of Clinical Nutrition ( 2000 ) 54 , 626–631
Inclusion of 95 % range in the model to account for inter-individual variability increased the predicted intake of vitamin D needed to maintain serum 25(OH)D ≥ 50 nmol/l to 930 IU/d .