Division of Endocrinology and Metabolism, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Laney Walker Blvd. CB2915, Augusta, GA, 30912, USA.
Osteoporos Int. 2018 Jun;29(6):1397-1405. doi: 10.1007/s00198-018-4451-7. Epub 2018 Mar 6.
Data gathered from a nationally representative cohort demonstrate that higher dietary protein intake was positively associated with the composite indices of femoral neck strength in both men and women, suggesting that higher protein intake may contribute to lower risk of hip fracture through the improvement of bone strength.
Despite the general belief that higher protein intake may be helpful for bone homeostasis, its impact on human bone health is still debated. Furthermore, the association of dietary protein intake with femoral neck (FN) strength, which can predict fracture risk independently of bone mineral density (BMD), has not been thoroughly studied.
This is a population-based, cross-sectional study from Korea National Health and Nutrition Examination Surveys, including 592 men aged 50 years or older and 590 postmenopausal women. The composite indices of FN strength, such as the compression strength index (CSI), bending strength index (BSI), and impact strength index (ISI), were generated by combining BMD, body weight, and height with the femoral axis length and width, which were measured by dual-energy X-ray absorptiometry.
After adjustment for confounders, total protein intake (g/kg/day) positively correlated with all three FN composite indices in both genders (P = 0.006 to 0.035), except for BSI showing marginal significance in postmenopausal women (P = 0.093). Consistently, compared with subjects in lowest total protein intake quartile, those in the highest quartile showed markedly higher CSI, BSI, and ISI values (P = 0.043 to < 0.001), with a dose-response manner across increasing total protein intake quartile categories in both men and women (P for trend = 0.028 to < 0.001).
These findings provide the clinical evidence that higher dietary protein intake can play a beneficial role on bone health through the increase of FN strength relative to load in adults.
本研究旨在通过韩国全国健康和营养检查调查，利用来自全国代表性队列的数据，探讨膳食蛋白质摄入量与男性和女性股骨颈（FN）强度综合指数之间的关联。
这是一项基于人群的横断面研究，共纳入了 592 名年龄在 50 岁及以上的男性和 590 名绝经后女性。通过双能 X 射线吸收法测量 FN 的骨密度（BMD）、体重、身高、股骨轴长和宽度，计算 FN 强度的综合指数，包括压缩强度指数（CSI）、弯曲强度指数（BSI）和冲击强度指数（ISI）。
在调整了混杂因素后，总蛋白质摄入量（g/kg/天）与男性和女性的所有三种 FN 综合指数均呈正相关（P 值分别为 0.006 至 0.035），但绝经后女性的 BSI 仅呈边缘显著（P=0.093）。同样，与最低总蛋白质摄入量四分位组的受试者相比，最高四分位组的 CSI、BSI 和 ISI 值明显更高（P 值分别为 0.043 至 <0.001），且在男性和女性中，随着总蛋白质摄入量四分位组的增加，呈现出明显的剂量反应关系（趋势 P 值=0.028 至 <0.001）。
这些发现提供了临床证据，表明较高的膳食蛋白质摄入量可通过增加 FN 强度来改善成年人的骨骼健康。
