Bone mineral density and serum 25-hydroxyvitamin D level:: is there any difference according to the dressing style of the female university students

Nutrition plays a role in the etiology of osteoporosis. Two of the most important nutrients for bone health are calcium and vitamin D. Plasma 25-hydroxyvitamin D [ 25-( OH) D] is the most sensitive clinical index of vitamin D status and has been found to be positively related to bone mineral density ( BMD) in middle- aged and elderly women, and positive relations exist between the BMD of adult women and their calcium consumption throughout life. The aim of the present study was to determine relationships between BMD, serum vitamin D levels and dietary calcium intake of female young adult students who dressed in different styles. We studied two groups of volunteer female students ( total = 67). Students in the first group dressed in a style that exposed the skin to sunlight, students in the second group wore dresses completely covering the skin except for the face and hands. Serum 25-( OH) D levels were measured by radioimmunoassay, BMDs were determined at the lumbar spine and femoral neck by dual-energy X-ray absorptiometry, and calcium intakes were estimated with a 3-day food recording questionnaire. The serum 25-( OH) D level was significantly lower in the second group. There was no significant difference in BMD between the two groups. The dietary calcium intake of the two groups were lower than the adequate intake of 1000 mg daily for this age. There was a correlation between the serum 25-( OH) D level and BMD at the femoral neck in the first group. Our results indicate that vitamin D and calcium requirements for normal bone mineral accrual in young adults may advance until a certain age, and the covered dressing style causes vitamin D insufficiency and most of the students were under risk for osteoporosis in later life.