Urinary phytate concentration and risk of fracture determined by the FRAX index in a group of postmenopausal women

Background/aim: This study was designed to evaluate the relationship between urinary phytate concentration and risk of fracture at 10 years, determined by using the FRAX model, in women who had undergone menopause within 5 years of the time of enrollment.

Materials and methods: Of the 212 postmenopausal women evaluated, 69 were excluded because they had urinary phytate concentrations between 0.51 and 0.99 mg/L. Of the remaining 143 women, 91 had low (≤0.50 mg/L) and 52 had high (≥1.0 mg/L) urinary phytate concentrations. The 10-year risk of fracture was calculated by using the FRAX model.

Results: The risks of major osteoporotic fracture and hip fracture were higher in women with low urinary phytate levels (P < 0.001 in both cases). Evaluation of the risk of hip fracture in women with and without risk factors for osteoporosis (e.g., tobacco, alcohol, and drug consumption) and according to urinary phytate concentrations indicated that, among women with no risk factors, those with low and high urinary phytate levels had a range of risks of 0%–0.6% and 0%–0.3%, respectively (P = 0.098). Moreover, among women with at least one risk factor, those with low and high urinary phytate had a range of risks of 0.1%–0.8% and 0.1%–0.4%, respectively (P = 0.002). Similar results were observed when the risks of major osteoporotic fracture were analyzed.

Conclusion: These results indicate the relationship of phytate with the risks of major osteoporotic fracture and hip fracture, with these differences being more marked in women with risk factors for osteoporosis. From this study follows the importance of the consumption of phytate-rich products (nuts, legumes, whole cereals) to protect against the risk of fracture in 10 years, mainly in women with risk factors for osteoporosis.