Tibial cortical bone properties of preadolescents and their mothers in an urban area associated with lifestyle: a longitudinal study.
OBJECTIVE
A 12-mo follow-up observation was performed to evaluate the tibial cortical bone properties of preadolescent children and their mothers in a densely populated area of Tokyo in association with their lifestyle in the context of healthy bone development of urban children.


METHODS
Fifty-four volunteer mother-child pairs were examined twice: once in the 1st grade of elementary school and once in the following year. Tibial cortical speed of sound (TCSOS) was measured by non-invasive quantitative ultrasonometry. Nutritional intake and recreational activity were examined using a structured interview.


RESULTS
TCSOS of the children showed a positive association with intake of vegetables, including potatoes and fruits (1st grade, r = 0.31, p < 0.05; 2nd grade, r = 0.33, p < 0.05), and inversely correlated with indoor recreational activities (1st grade, r = -0.28, p < 0.05). The z-score of TCSOS of the mothers was correlated with intake of milk, dairy products and eggs (r = 0.35, p < 0.001). However, there were no statistically significant correlations in TCSOS between children and their mothers.


CONCLUSIONS
A 1-y longitudinal study in urban children indicated the effects of specific types of food intake and recreational activities of children on tibial bone properties.
Health Promotion/International Health, Graduate School of Tokyo Medical and Dental University, Tokyo, Japan.
Tomoko
T
Inose
Takehito
T
Takano
Keiko
K
Nakamura
Masashi
M
Kizuki
Kaoruko
K
Seino
D000328:Adult; D015519:Bone Density; D002648:Child; D004032:Diet; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D009035:Mothers; D011998:Recreation; D013977:Tibia / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography; D014504:Urban Health