Space Nutrition: A Thriving Field Extending New Possibilities

History of Food in Space

For long travels and journeys, we generally carry food with us. Snacks, or sometimes meals worth several days to survive. When there were no fast vehicles or methods for swift transportation, it was a rudimentary requirement to carry meals along, especially in long sea voyages or traveling to another country. 

Space is within our reach today, but it is still isolated in terms of putting a regular appearance. Astronauts in space have to dwell with conditions unfavorable to human inhibition and therefore need good care of their bones and muscles. Nutrition enriched foods help in preserving the situation, but food items in their original shape could be troublesome to carry in the space. After the Apollo 11 exploration in 1969, the concept of nutrition for astronauts needed to be revolutionized. 

 

Mercury Program Food

John Glenn was the first American to eat in space aboard Friendship 7 in 1962. At that time, it was not known if ingestion and absorption of nutrients were possible in a state of zero gravity. Glenn's consumption of applesauce, packed in a tube, and xylose sugar tablets with water, demonstrated that people could eat, swallow, and digest food in a weightless environment. 

Beef and Vegetables

This space food package containing pureed beef and vegetables was issued to John Glenn for consumption during his Friendship 7 flight in February 1962. Space food for the Mercury missions was placed in tube form to enable the astronauts to squeeze it directly into their mouths. 

 

Bone and Nutrition in Space Flight 

Nutrition is critical for virtually all systems. The interaction of nutrition with bone is perhaps more extensive and complex than most of its interactions with body systems. Many nutrients are important for healthy bone, particularly calcium and vitamin D. When food containing calcium is eaten, the calcium is absorbed by the intestines and goes into the bloodstream. The absorption of calcium from the intestines decreases during spaceflight. Even when astronauts take extra calcium as a supplement, they might still lose bone. Sodium intake is also a concern during spaceflight because space diets tend to have relatively high amounts of sodium. Increased dietary sodium is associated with increased amounts of calcium in the urine and may relate to the increased risk of kidney stones. The potential effect of these and other nutrients on the maintenance of bone health during spaceflight highlights the importance of optimal dietary intake. 

 

Gastrointestinal function during space missions

Astronauts experience gastrointestinal changes early in the flight, gaseous stomach occurs due to the inability of gases to rise. Furthermore, the effects of micro-gravity are presumed to alter the contact of the gastric contents with the gastrointestinal mucus. However, cephalic fluid shifts, in combination with commonly observed dehydration, could affect gastrointestinal motility through reduced splanchnic flow. The effect of chronic inactivity increases transit time and potentially changes gastrointestinal microflora. Gastrointestinal integrity and bacterial balance may be improved by probiotics and prebiotics that should be studied for possible inclusion in space foods. 

 

Iron metabolism during space flight

Space flight-induced hematologic changes have been observed since the initial days of space exploration. Space flight anemia is a widely recognized phenomenon in astronauts. The implications of hematologic changes for long-term space flight may have consequences on the health of astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. 

 

Food technology for space journeys has evolved a lot with time and getting more attention now as humans are investing in the idea of colonizing distant planets. Understanding human metabolism in space and innovations to meet the challenge is in demand. If you want to be a Space Nutritionist, this is a perfect time to explore this field. 

To Read More About Space Nutrition, Refer to this Book by the National Aeronautics and Space Administration: Space_Nutrition_Book