Rambaut P C, Smith M C, Leach C S, Whedon G D, Reid J
Fed Proc. 1977 Apr;36(5):1678-82.
Prior to the Mercury program, extensive efforts were undertaken to find ways of minimizing the mass of in-flight food systems. Such efforts were directed to the use of dehydrated, energy-dense foodstuffs and to the possibilities of nutrient recyclization. As the space program became a reality, nutritional scientists were more concerned with the mechanics of food consumption in weightless flight and with the problems of structuring convention foods in a way that would facilitate their use in weightlessness. It soon became clear that there was no substantial impediment to normal gastrointestinal function in flight, and attention was shifted to more subtle metabolic phenomenons. It became apparent that slight changes occurred in skeletal density, muscle mass, and overall body composition. Recognition of these changes led to extensive ground-based simulation studies and carefully designed in-flight experiments. Data are presented on the requirements for metabolic energy in flight and on the losses that have been observed in the major elemental constituents of the body. It is concluded that convincing evidence is not yet avialable on the ability of man to adapt to long-term weightless flight. Although his nutritional requirements are qualitatively similar during flight, the sophisticated manipulation of nutrient profiles shows promise of counteracting some of the deteriorative processes that are known to occur.
在水星计划之前，人们进行了广泛的努力，以寻找使飞行中食品系统质量最小化的方法。这些努力旨在使用脱水的、能量密集的食品以及营养物质循环利用的可能性。随着太空计划成为现实，营养科学家更加关注失重飞行中食物消耗的机制，以及如何将传统食物进行结构化处理，以便于在失重状态下使用。很快就清楚了，飞行中正常的胃肠功能没有实质性障碍，于是注意力转移到更细微的代谢现象上。很明显，骨骼密度、肌肉质量和整体身体成分发生了轻微变化。对这些变化的认识导致了广泛的地面模拟研究和精心设计的飞行实验。文中给出了飞行中代谢能量需求的数据以及在人体主要元素成分中观察到的损失数据。得出的结论是，关于人类适应长期失重飞行能力的令人信服的证据尚未可得。虽然他在飞行期间的营养需求在质量上相似，但对营养成分的精细调控有望抵消一些已知会发生的退化过程。
