New Year, Old Habits: Eating Right in Space is a Long-Term Resolution

    HOUSTON, TX, January 26, 2015 /24-7PressRelease/ -- As the world celebrates the New Year, many people make resolutions to improve their general well-being, whether mentally, emotionally or physically.

The common resolution to watch food intake is a way of life for astronauts on the International Space Station, especially when they spend six months of their lives in orbit. What researchers can learn from astronauts' ongoing good habits may one day help us at home with our own healthy choices.

Nutrition and exercise are part of a daily requirement for astronauts on and off the planet. One of the reasons is there are no quick trips to the doctor or the grocery store when you are more than 200 miles above Earth's surface.

"We evaluate nutrition and basic physiology of space station crew members to keep them safe and healthy," said Scott M. Smith, Ph.D., a nutritional biochemist at NASA's Johnson Space Center in Houston. "We need to learn everything we can about how humans adapt to the environment of space, and how nutrition might play a role in keeping them healthy. We collect blood and urine samples during their flights to measure vitamins and minerals and other biochemical markers to monitor how they're doing and compare the data to their dietary intake, exercise and other factors."

Investigators on Earth also look at these chemical markers to better understand the medical issues that occur during spaceflight.

"Bone and muscle loss is a major issue when it comes to long-duration spaceflight," Smith said. "Another concern is crew members coming back from the space station with vision problems. Some go up with perfect vision and come home needing glasses while others don't have any trouble at all. From the blood samples we analyzed, we learned there are differences in the biochemical profiles of those astronauts, so we're following up on that to better understand those changes."

Studying the nutrients humans in space use to fuel their bodies can provide clues to changes in human physiology during flight. The results of one study, the Nutritional Status Assessment investigation on the space station, will help determine the optimum nutritional requirements for humans in space and on the ground.

The Nutritional Status Assessment study was conducted with astronauts for more than seven years, taking numerous in-flight samples of body fluids and looking at various hormone levels, bone metabolism, vitamin status and antioxidants. Although the study ended in 2013, the samples are still being processed and analyzed. However, preliminary results led scientists and physicians to revise vitamin D supplement recommendations for astronauts, and ground-analog research in Antarctica has contributed to a new dietary reference intake for people in North America, not just space travelers.

"Based on the findings from the nutrition study, we decided to follow it up with a closer look at the physiology and biochemistry of individual astronauts," Smith said. "The Biochemical Profile project tests blood and urine samples from astronauts before, during and after flight. Specific proteins and chemicals in the samples are used as health indicators for individual astronauts, and post-flight analysis will help create a database we can use to study the effects of spaceflight on the body."

Smith says the next logical step is an integrated effort to modify the diets of crew members during flight. Providing healthier menus not only would mitigate some of the negative effects of spaceflight on the human body, but it would also provide insight into improving nutrition for humans around the world. Understanding basic physiology and nutritional requirements can help us better understand those same things on Earth.

"For example, bone loss experienced during spaceflight is similar to the bone disease of people on Earth," Smith said. "Studying it in our astronauts, already a very healthy segment of the population, helps us better understand the nature of the disease and develop countermeasures for all of us -- be it dietary changes, exercises or pharmaceutical remedies."

While you may have resolved to improve your own diet, space station astronauts are making those same resolutions for the benefit of humanity. The results of these and other ongoing and future investigations will serve both Earth-bound citizens and those who will eventually set foot on another planet. Because, while we make great strides in exploration, you won't find a health food store on Mars. Not yet anyway.

By Bill Hubscher
NASA's Marshall Space Flight Center

# # #