Effect of vitamin D supplementation on vitamin D status and bone turnover markers in young adults.
OBJECTIVE
To assess the vitamin D status of healthy young people living in Northern Ireland and the effect of vitamin D supplementation on vitamin D status and bone turnover.


METHODS
Double-blinded randomised controlled intervention study.


METHODS
University of Ulster, Coleraine, Northern Ireland.


METHODS
In total, 30 apparently healthy students (15 male and 15 female subjects), aged 18-27 years, were recruited from the university, with 27 completing the intervention.


METHODS
Subjects were randomly assigned, to receive either 15 microg (600 IU) vitamin D(3) and 1,500 mg calcium/day (vitamin D group), or 1,500 mg calcium/day (control group) for 8 weeks between January and March. Vitamin D status, bone turnover markers, serum calcium and parathyroid hormone concentrations were measured at baseline and post intervention.


RESULTS
At baseline, vitamin D status was low in both the vitamin D group (47.9 (s.d. 16.0)) and the control group (55.5 (s.d. 18.6) nmol/l 25(OH)D). Post intervention vitamin D status was significantly higher in the vitamin D-treated group (86.5 (s.d. 24.5)) compared to the control group (48.3 (s.d. 16.8) nmol/l) (P<0.0001). There was no significant effect of supplementation on bone turnover markers or PTH concentrations.


CONCLUSIONS
This study suggests that young adults in Northern Ireland do not consume an adequate daily dietary intake of vitamin D to maintain plasma vitamin D concentrations in the wintertime. A daily supplement of 15 microg vitamin D(3) significantly increased vitamin D status in these individuals to levels of sufficiency. Achievement of an optimum vitamin D status among young adults may have future positive health implications.
Barnes
M S
MS
Northern Ireland Centre for Food and Health, University of Ulster, Coleraine, Northern Ireland, UK.
Robson
P J
PJ
Bonham
M P
MP
Strain
J J
JJ
Wallace
J M W
JM
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism*; D002136:Calcium, Dietary / Q000008:administration & dosage* / Q000097:blood; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D007494:Ireland; D008297:Male; D009752:Nutritional Status; D010281:Parathyroid Hormone / Q000097:blood; D012621:Seasons; D014807:Vitamin D / Q000008:administration & dosage* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000517:prevention & control
D015415:Biomarkers; D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary; D010281:Parathyroid Hormone; D014807:Vitamin D