Abstract:
Optimal bone health is important in children to reduce the risk of osteoporosis later in life.
Both body composition and vitamin D play an important role in bone health. This study aimed to
describe bone health, body composition, and vitamin D status, and the relationship between these
among a group of conveniently sampled black preadolescent South African children (n = 84) using a
cross-sectional study. Body composition, bone mineral density (BMD), and bone mineral content
(BMC) were assessed using dual x-ray absorptiometry. Levels of 25-hydroxyvitamin D (25(OH)D)
(n = 59) were assessed using dried blood spots. A quarter (25%) of children presented with low
bone mass density for their chronological age (BMD Z-score < 2) and 7% with low BMC-for-age
(BMC Z-score < 2), while only 34% of the children had su cient vitamin D status (25(OH)D
30 ng/mL). Lean mass was the greatest body compositional determinant for variances observed in
bone health measures. Body composition and bone health parameters were not significantly di erent
across vitamin D status groups (p > 0.05), except for lumbar spine bone mineral apparent density
(LS-BMAD) (p < 0.01). No association was found between bone parameters at all sites and levels of
25(OH)D (p > 0.05). Further research, using larger representative samples of South African children
including all race groups is needed before any conclusions and subsequent recommendation among
this population group can be made.
