Gender-dependent skeletal effects of vitamin D deficiency in a younger generation

Context: The major health threats caused by vitamin D deficiency in the young generation have not been fully elucidated. Objective: The aim of this study was to investigate skeletal and nonskeletal effects of vitamin D deficiency and to study the optimal level of serum 25-hydroxyvitaminD[25(OH)D] in young people. Design and Setting: The Fourth Korea National Health and Nutrition Examination Surveys (KNHANES IV) was conducted in 2008-2009. Participants:Atotal of 4276 people (1926menand 2350women)aged 10-40 yr were selected from 16 administrative districts of South Korea. Main Outcome Measures: We measured age-specific changes in bone mineral density (BMD) according to serum 25(OH)D. Results: Serum 25(OH)D was less than 25 nmol/liter in 18.8% of participants, 25 to less than 50 nmol/liter in 50.0%, 50 to less than 75 nmol/liter in 27.0%, and 75 nmol/liter or greater in 4.2%. Vitamin D deficiency was more frequent in women than in men. There were gender differences in the skeletal effects of vitaminDdeficiency. Inmenbetween 10 and 22 yr old,BMDwas significantly higher in the vitamin D-sufficient group,andinmenbetween23and40 yr old, a positive correlation betweenserum25(OH)DandBMDwasobserved. However, inwomen,wecould not find significant differences inBMDaccording to vitaminDstatus. VitaminDdeficiency in younger generations had no remarkable effects on most nonskeletal parameters or on the prevalence of concomitant diseases except for rheumatoid arthritis. Conclusions: Vitamin D plays an essential role in skeletal health of young people. Moreover, the presence of gender-dependent skeletal effects was an important observation of this study. Reassurance of serum 25(OH)D up to 20-30 ng/ml or higher is necessary, especially during the modeling phase in men.