Self-Reported Dietary Intake of Omega-3 Fatty Acids and Association with Bone and Lower Extremity Function

OBJECTIVES To assess the relationship between self-reported omega-3 fatty acid (O3FA) intake and bone mineral density (BMD) and lower extremity function in older adults. DESIGN Cross-sectional analysis of baseline information from three separate ongoing studies of older adults, pooled for this analysis. SETTING Academic health center. PARTICIPANTS Two hundred forty-seven men (n=118) and women (n=129) residing in the community or an assisted living facility. MEASUREMENTS Self-reported dietary intake (O3FA, omega-6 fatty acids (O6FA), protein, and total calorie); BMD of the hip or heel; and lower extremity function including leg strength, chair rise time, walking speed, Timed Up and Go, and frailty. RESULTS The mean reported intake of O3FA was 1.27 g/day. Correlation coefficients (r) between O3FA and T-scores from total femur (n=167) were 0.210 and 0.147 for combined femur and heel T scores. Similar correlations were found for leg strength (r=0.205) and chair rise time (r=-0.178), but the significance was lost when corrected for protein intake. Subjects with lower reported O3FA intake (< 1.27 g/day) had lower BMD than those with higher reported O3FA intake. In a multiple regression analysis with femoral neck BMD as the dependent variable and reported intake of O3FA, O6FA, protein, and vitamin D as independent variables, reported O3FA intake was the only significant variable, accounting for 6% of the variance in BMD. CONCLUSION Older adults had low reported intakes of O3FA. There was an association between greater reported O3FA intake and higher BMD. There was no independent association between reported O3FA intake and lower extremity function. Results from this preliminary report are promising and suggest further investigation.