Role of Nutrition during Long-Term Spaceflight.

Abstract

It is apparent that composition and quantity of dietary intake has a profound effect on human health. Therefore, provision of adequate food and nutrition is one of the foremost challenges facing long-termspaceflight. This includes recognition of the manner in which weight-lessness alters human metabolism and provision for adequate life support. Since the beginning of manned spaceflight, there has been a steady improvement in the understanding of nutritional needs as missions have increased from days to weeks to one year in duration. But our knowledge of changes in nutritional requirements due to microgravity is far from complete. To date, measures used have been almost entirely empiric and focused on providing a near Earth-like environment and palatable diet. Interplanetary travel will be impos- sible without recycling wastes, generating drinkable water, and growing a limited number of food stuffs. Now emphasis must shift to a more thorough understanding of the fundamental processes involved with long-term stays in space and appropriate application of proce- dures leading to amelioration of induced changes. The following chapter will discuss those changes in macro- and micro-nutrients which are known to occur with weightlessness and present relevant considerations for maintaining appropriate nutrition during prolonged space missions. Special attention will be focused on two minerals, sodium and calcium, which are known to show important changes in the human body during spaceflight.