Correlates of Forearm Bone Mineral Density in Young Norwegian Women: the Nord-Trøndelag Health Study

Maximizing attainment of optimal peak bone mineral density (BMD) is a potential osteoporosis prevention strategy. The main objective of this study was to identify correlates of forearm BMD in young adult women. Population-based data derived from standardized questionnaires administered to healthy women aged 19-35 years in Nord-Trøndelag, Norway (n = 963), were collected in 1995-1997. Forearm BMD was assessed by single x-ray absorptiometry. Multiple linear and logistic regression analyses were used to determine correlates of BMD (g/cm(2)) and lowest quintile of BMD, respectively, at the ultradistal and distal sites. The mean age and weight of the cohort were 29.7 years (standard deviation 4.7) and 68.6 kg (standard deviation 12.5), respectively. Age and weight were positively associated with BMD at both forearm sites. When data were controlled for age and weight, later age at menarche and lack of milk consumption were associated with lower BMD values. In both linear models and logistic models, none of the factors vitamin D intake, physical activity, smoking, alcohol consumption, amenorrhea, oral contraceptive use, number of pregnancies, history of breastfeeding, and family history of osteoporosis were found to be significantly associated with BMD. Prior studies have suggested that calcium supplementation in children is useful for optimizing peak BMD. Further studies exploring the relation between lifestyle factors and BMD are warranted to search for ways to maximize attainment of peak BMD.