Quality of diet and potential renal acid load as risk factors for reduced bone density in elderly women

Background: Bone mineral density (BMD) may be influenced by the general dietary pattern and the potential renal acid load (PRAL). Methods: We compared the dietary intake (estimated using the European Prospective Investigation into Cancer and nutrition questionnaire) of 497 community-living women (60 years of age and older) grouped according to tertiles of baseline total, trabecular and cortical BMD estimated using tibial peripheral quantitative computed tomography (pQCT), and of BMD variation over 6 years. Results: None of the nutrients taken into account nor PRAL was associated with total BMD, with the exception that the intake of polyunsaturated fatty acids (PUFA) was slightly higher among women with the highest total BMD. Similar results were found for trabecular BMD. Cortical BMD was associated with serum 25-OH vitamin D (38.8, 43.2, and 49.5 nmol/L in the first, second, and third tertiles, respectively; P=0.042). In the longitudinal analysis, a lower BMI was associated with greater loss of total BMD, while lower serum 25-OH vitamin D at baseline was associated with smaller loss of cortical BMD. Conclusions: We found no relationship between dietary acid load and BMD. We also confirmed the role of well-recognized risk factor for osteoporosis.