Nakamura Kazutoshi, Hori Yasushi, Nashimoto Mitsue, Okuda Yoko, Miyazaki Hideo, Kasai Yasunori, Yamamoto Masaharu
Department of Community Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Nutrition. 2004 Apr;20(4):340-5. doi: 10.1016/j.nut.2003.12.004.
Associations between dietary factors and bone metabolism in Asians have not been thoroughly investigated. The purpose of this study was to determine the effect of dietary intake of calcium (Ca), phosphorus (P), sodium (Na), and protein on bone metabolism in elderly Japanese women by the duplicate portion sampling method.
The subjects were 43 healthy female volunteers (mean age, 68.3 y; standard deviation, 6.8). Dietary nutrients were directly determined by using a 24-h duplicate meal portion. Serum osteocalcin and bone alkaline phosphatase and urinary deoxypyridinoline (DPD) and type I collagen cross-linked N-telopeptides (NTX-I) were measured as markers of bone turnover. Hormones related to bone metabolism, including serum 25-hydroxyvitamin D(3), 1,25-dihydroxyvitamin D(3), and intact parathyroid hormone also were determined. Urinary parameters were corrected for urinary creatinine concentration.
The mean (standard deviation) daily dietary intakes of Ca, P, Na, and protein were 660 (195) mg, 996 (208) mg, 4080 (1142) mg, and 63.9 (15.5) g, respectively. Dietary Ca was negatively correlated with urinary DPD (r = -0.417, P = 0.005) and NTX-I (r = -0.324, P = 0.034), and dietary P was negatively correlated with urinary DPD (r = -0.307, P = 0.045). Multiple regression analysis showed that only dietary Ca was associated with urinary DPD and NTX-I. Dietary Ca intake was significantly associated with bone resorption markers, but no other dietary factors were associated with any of the biochemical markers.
The major factor having an adverse effect on the bone health of the elderly Japanese women is low Ca intake and not other dietary minerals or protein.
亚洲人饮食因素与骨代谢之间的关联尚未得到充分研究。本研究的目的是通过双份膳食样本采集法，确定钙（Ca）、磷（P）、钠（Na）和蛋白质的膳食摄入量对老年日本女性骨代谢的影响。
研究对象为43名健康女性志愿者（平均年龄68.3岁；标准差6.8）。通过24小时双份膳食样本直接测定膳食营养素。测定血清骨钙素、骨碱性磷酸酶以及尿脱氧吡啶啉（DPD）和I型胶原交联N端肽（NTX-I）作为骨转换标志物。还测定了与骨代谢相关的激素，包括血清25-羟基维生素D(3)、1,25-二羟基维生素D(3)和完整甲状旁腺激素。尿参数根据尿肌酐浓度进行校正。
Ca、P、Na和蛋白质的每日膳食平均摄入量（标准差）分别为660（195）mg、996（208）mg、4080（1142）mg和63.9（15.5）g。膳食Ca与尿DPD（r = -0.417，P = 0.005）和NTX-I（r = -0.324，P = 0.034）呈负相关，膳食P与尿DPD（r = -0.307，P = 0.045）呈负相关。多元回归分析表明，仅膳食Ca与尿DPD和NTX-I相关。膳食Ca摄入量与骨吸收标志物显著相关，但其他膳食因素与任何生化标志物均无关联。
对老年日本女性骨骼健康产生不利影响的主要因素是Ca摄入量低，而非其他膳食矿物质或蛋白质。
