Conflicting results on associations between dietary quality and bone have been noted across populations, and this has been understudied in Puerto Ricans, a population at higher risk of osteoporosis than previously appreciated.
To compare cross-sectional associations between 3 dietary quality indices [Dietary Approaches to Stop Hypertension (DASH), Alternative Health Eating Index (AHEI-2010), and Mediterranean Diet Score (MeDS)] with bone outcomes.
Participants (n = 865–896) from the Boston Puerto Rican Osteoporosis Study (BPROS) with complete bone and dietary data were included. Indices were calculated from validated food frequency data. Bone mineral density (BMD) was measured using DXA. Associations between dietary indices (z-scores) and their individual components with BMD and osteoporosis were tested with ANCOVA and logistic regression, respectively, at the lumbar spine and femoral neck, stratified by male, premenopausal women, and postmenopausal women.
Participants were 59.9 y ± 7.6 y and mostly female (71%). Among postmenopausal women not taking estrogen, DASH (score: 11–38) was associated with higher trochanter (0.026 ± 0.006 g/cm2, P <0.001), femoral neck (0.022 ± 0.006 g/cm2, P <0.001), total hip (0.029 ± 0.006 g/cm2, P <0.001), and lumbar spine BMD (0.025 ± 0.007 g/cm2, P = 0.001). AHEI (score: 25–86) was also associated with spine and all hip sites (P <0.02), whereas MeDS (0–9) was associated only with total hip (P = 0.01) and trochanter BMD (P = 0.007) in postmenopausal women. All indices were associated with a lower likelihood of osteoporosis (OR from 0.54 to 0.75). None of the results were significant for men or premenopausal women.
Although all appeared protective, DASH was more positively associated with BMD than AHEI or MeDS in postmenopausal women not taking estrogen. Methodological differences across scores suggest that a bone-specific index that builds on existing indices and that can be used to address dietary differences across cultural and ethnic minority populations should be considered.