Food intake and nutritional status during EXEMSI. Experimental Campaign for the European Manned Space Infrastructure.

Modifications of food intake by astronauts during long-duration spaceflights have been observed. Various psychological stress factors, such as isolation, confinement, constrained community and boredom, are thought to play a role in this phenomenon. For this reason it was decided to include a nutritional investigation in the EXEMSI simulation study, in which four crew members (1 female and 3 males) were isolated and confined for 60 days in a space station-like environment. The Food and Nutritional Management System, developed for this experiment, provided on-line analysis of all available foods in terms of their nutrient content (macronutrients, water, minerals, vitamins). It permitted to keep an accurate record of the daily food intake of each crew member. The system has been shown to be a powerful tool for future missions, either simulations or actual spaceflights. It permits optimal management of food and eating on board, and offers the possibility of online analysis of the nutritional status of the crew. It can provide readily usable data for future analysis of nutritional variables in relation to other physiological and metabolic parameters. It could also supply a periodic feedback to the subject for the purpose of adjusting food intake. Eating and nutrition during the experiment were not a problem, but a pleasure, and therefore played an important role in its success. Confinement and isolation apparently had no effect on either the eating habits or the nutritional status of the crew members. The good food rather helped to decrease the potentially induced stress by providing daily periods of pleasure and of social activities. Detailed analysis of food intake showed erratic eating patterns, both before and during the experiment. However, the weekly averages of macro- and micronutrient intakes were in the normal range, except for vitamins B1 and B6 that were rather low and showed the need for supplements. Food appreciation was assessed by daily questionnaires. Satisfaction with the food provided during isolation was rated very high, and there was no feeling of hunger or monotony. The satisfaction with the food was mainly due to its high palatability, the adequate selection made with direct prior involvement of the crew, the large variety, and the extra supply that allowed the crew to choose and feel free regarding food intake. Comments from the crew afterwards clearly demonstrated that food had not been considered critical during the 60 days of isolation. This is an important fact considering the importance of food in such a restricted living environment.