Dietary and Non-dietary Factors Related to Bone Mineral Density in Female College Students

Lim, Ji Hye; Bae, Hyun Sook; Lee, Seung Min; Ahn, Hong Seok

Abstract

The purpose of this study was to investigate correlations between bone mineral density (BMD) and dietary and nondietary factors in female college students. The BMD of the subjects (n = 38) was measured using DEXA (Dual Energy X-ray Absorptiometry) at lumbar spine and three femoral sites including femoral neck, ward's triangle, and femoral trochanter. Three-day 24-hour dietary recall data were collected from each subject to assess consumption levels of nutrients and food groups. The mean (+/- SD) values of age, age of menarche, height, weight, body mass index (BMI), waist-to-hip ratio (WHR), fat mass, and % body fat of the subjects were 21.34 (+/- 1.73) years, 13.1 (+/- 1.2) years, 161.3 (+/- 5.0) cm, 53.7 (+/- 7.2) kg, 20.6 (+/- 2.6) kg/m2, 0.80 (+/- 0.04), 15.4 (+/- 4.4) kg, and 28.2 (+/- 4.7), respectively. The BMD values of lumbar spine, femoral neck, ward's triangle, and femoral trochanter as T-value were 1.150 +/- 0.13 g/cm2, 0.932 +/- 0.11 g/cm2, 0.850 +/- 0.13 g/cm2, and 0.721 +/- 0.10 g/cm2, respectively. The daily mean energy intake of the subjects was 1660.6 kcal. The intake levels of carbohydrate, calcium, iron, vitamin C, and folic acid were lower than the KDRIs, while those of fat, phosphorus, sodium, vitamin A, and vitamin B6 were higher than the KDRIs. Significantly negative correlation were detected between consumption of fat and oils and the BMD of all sites measured (p < 0.05). Potato and starch intake was negatively correlated to the BMD of femoral neck and word's triangle (p < 0.05). The intake of cereals was found to be negatively correlated to the BMD of ward's triangle (p < 0.05). There was also negative correlation of intake of soybeans and products with the BMD of lumbar spine (p < 0.05). Weight and muscle mass were positively correlated to the BMD of both lumbar spine and femurs (p < 0.01). Significantly positive correlations between BMI, and fat mass and the BMD of lumbar spine were observed (p < 0.001). Additionally fat mass was positively correlated to the BMD of femoral neck. WHR and % body fat were positively correlated to the BMD of lumbar spine (p < 0.05). Negative correlation was found between a serum calcium level and the BMD of femoral neck (p < 0.05). In summary non-dietary factors generally showed significant correlations with the BMD of lumbar spine, while several dietary factors showed significant correlations with the BMD of femurs.