PHYSIOLOGY OF AGING

对生理系统年龄变化的研究包括肾脏， 心血管和新陈代谢区域。特别令人感兴趣的是， 饮食营养素摄入量与生理的关系。 其中包括蛋白质摄入对肾脏的影响。 功能(肌酐清除)、钙和蛋白质的作用 摄入量对骨丢失的影响，以及膳食纤维摄入量对 心血管危险因素。 蛋白质摄入和钙摄入的影响是不同的。 从这些理论上来看。因此，较高的蛋白质摄入量没有影响。 对同步肾功能也没有任何影响 在饮食估计后至少10年测量肾功能) 与骨矿物质无关(在X射线上估计为 皮质骨厚度)与饮食同时进行 测量或至少10年后。纤维估计是 与心脏病的某些危险因素有关(血压、 甘油三酯和空腹血糖)(见代谢部分)。 女性在接受葡萄糖治疗后的两小时血糖水平 耐力测试与记忆心理测试无关， 词汇量或反应时间，但与 认知能力测试的表现(概念问题 正在解决。) 平均血压值与血压下降的速度无关 中老年血压正常男性254例肾功能分析 正常范围。当包括更高水平的血压时 在分析中，与较高的压力有关 与更快的肾功能丧失有关。

Studies of age changes in physiologic systems have included renal, cardiovascular, and metabolic areas. Of particular interest, has ben the relationship of dietary intake of nutrients to physiology. These have included the effects of protein intake on renal function (creatinine clearance), the effect of calcium and protein intake on bone loss, and the effect of dietary fiber intake on cardiovascular risk factors. The effects of both protein intake and calcium intake differed form those theorized. Thus, higher protein intake had no effect on simultaneous renal function nor did it have any effect on kidney function measured at lease 10 years after diet estimates) had no relationship to bone mineral (estimated on X-ray by the thickness of cortical bone) either at the same time as the dietary measurements or at least 10 years later. Fiber estimates were related to certain risk factors for cardiac disease (blood pressure, triglyceride and fasting pasma glucose) (see Metabolism Section). The two hour glucose levels of females undergoing glucose tolerance test was not related to psychological test of memory, vocabulary, or reaction time but were significantly related to performance on a test of cognitive ability (conceptual problem solving.) Mean blood pressure values were not related to the rate to fall in renal function in 254 normal men with blood pressures in the normal range. When higher levels of blood pressure were included in the analysis there was a relationship with higher pressures being associated with more rapid loss of renal function.