Associations of dietary polyunsaturated fatty acids with bone mineral density in elderly women

Significance of dietary fatty acids on bone health is not clear, and the evidence is controversial. This study aimed to investigate the relationship between dietary polyunsaturated fatty acids (PUFAs) and bone mineral density (BMD) among elderly women.

Subjects (n=554) were drawn from the Kuopio OSTPRE Fracture Prevention Study. At baseline they filled a 3-day food record and a questionnaire on lifestyle factors, diseases and medications. BMD was measured at lumbar spine (L2-L4), femoral neck and total body by dual energy X-ray absorptiometry at baseline and after 3 years. The associations between dietary fatty acids and BMD were analyzed by a linear mixed model adjusting for potential dietary and non-dietary confounders.

Our findings suggested a positive relationship between the dietary PUFAs and BMD at lumbar spine and in total body but not at femoral neck. Further analyses revealed that these results were due to associations among the women without hormone therapy (HT) at baseline. Among them, the intake of total PUFAs as well the intakes of linoleic and linolenic acids and total n-3 and n-6 fatty acids were significantly associated with BMD at lumbar spine; P for trend over the quartiles ranged between 0.013 and 0.001. Similarly, significant associations were demonstrated for total body BMD and fatty acids with an exception of total PUFA. No significant associations were found among women with HT at baseline.

Our findings among elderly women without HT support the suggested beneficial effect of dietary PUFAs on bone health.