Differences in peak bone density between male and female students.

As an important determinant of osteoporotic fracture risk, peak bone density tends to be higher in men than in women. The aim of this study was to see whether young men and women differed in the time and skeletal region of peak bone density. We also investigated the influence of diet and physical activity on bone mass. The study group included 51 male and 75 female students aged 19 to 25 years. Bone mineral density was measured for the spine, total femur, and the distal third of the radius using dual energy x-ray absorptiometry. Dietary data were obtained using a specially designed semiquantitative food frequency questionnaire. Bone mineral density (BMD; g cm(-2)) was higher in boys than in girls at all measured sites, while bone mineral apparent density (BMAD; g cm(-3)) was higher in girls. Age negatively correlated with bone mineral density in all measured sites except in the boys' spine. Sodium, protein, and fibres were nutrients that significantly correlated with bone mineral density. The study suggests that boys achieve peak bone density later than girls, and that this delay is the most prominent in the spine. In our study group, this difference could not be explained by different nutrition or the level of physical activity.