Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 361

Advanced age is associated with diminished homeostatic regulation of many physiological functions, including the regulation of energy intake. For example, Roberts et al. underfed 17 young and old men by 3.17 MJ per day (~750 kcal per day) for 21 days, during which time both the young and old men lost weight. After the underfeeding period, the men were allowed to again eat ad libitum. The young men ate more than at baseline (pre‐underfeeding) and quickly returned to normal weight, whereas the old men did not compensate, returned only to their baseline intake, and did not regain the weight they had lost. Older adults also have a reduced ability to detect and respond to dehydration. Consequently, after an anorectic insult (for example, major surgery), older adults are likely to take longer than young adults to regain the weight lost, remain undernourished longer, and be more susceptible to subsequent superimposed illnesses, such as infections.²⁹