Morley J E
Geriatric Research, Education and Clinical Center, Saint Louis VA Medical Center, Missouri 63104, USA.
J Gerontol A Biol Sci Med Sci. 2001 Oct;56 Spec No 2:81-8. doi: 10.1093/gerona/56.suppl_2.81.
There is a physiological decline in food intake with aging. The reasons for the decline in food intake are multifactorial and involve both peripheral and central mechanisms. Altered hedonic qualities of food occur due to alterations in taste and, more particularly, smell with aging. A decline in adaptive relaxation of the fundus of the stomach and an increased rate of antral filling appear to play a role in the early satiation seen in many older persons. Cholecystokinin levels are increased with aging and older persons are more sensitive to the satiating effects of this gut hormone. The decline in testosterone levels in older males leads to increased leptin levels and this may explain the greater decline in food intake with aging in the male. Within the hypothalamus, decreased activity of both the dynorphin (kappa opioid) and neuropeptide Y systems occurs in aging rodents. Cytokines are potent anorectic agents. Many older persons have mild inflammatory disorders that lead to anorexia. Exercise may increase food intake in older persons.
随着年龄增长，食物摄入量会出现生理性下降。食物摄入量下降的原因是多方面的，涉及外周和中枢机制。随着年龄增长，味觉尤其是嗅觉的改变会导致食物享乐品质的变化。胃底适应性舒张功能下降以及胃窦充盈速率增加，似乎在许多老年人出现的早期饱腹感中起作用。随着年龄增长，胆囊收缩素水平升高，老年人对这种肠道激素的饱腹感作用更敏感。老年男性睾酮水平下降导致瘦素水平升高，这可能解释了男性随着年龄增长食物摄入量下降幅度更大的原因。在衰老的啮齿动物中，下丘脑内强啡肽（κ阿片样物质）和神经肽Y系统的活性均降低。细胞因子是强效的食欲抑制剂。许多老年人患有轻度炎症性疾病，会导致食欲不振。运动可能会增加老年人的食物摄入量。
