How a Year in Space Affects the Human Body

Science fiction has long promised an age of interplanetary human existence. Scenes of spaceships hopping from one galaxy to the next are so common, it seems almost inevitable that future generations will one day vacation on Mars. But, if we are ever going to achieve life on other planets, we first have to figure out if the human body can tolerate it.

Some of the best data we have on the subject comes from American astronaut Scott Kelly. Kelly spent a year living on the International Space Station while his twin brother Mark, also an astronaut, was on Earth. Scientists from all over the country studied the impact life in space had on Scott Kelly, and compared changes in his body to his brother.

One of those scientists was UC San Diego Professor of Medicine, Michael G. Ziegler, MD. In a recent talk at UC San Diego Extension’s Osher Lifelong Learning Institute, Ziegler detailed some of the more interesting findings from the study. Scott Kelly lost weight. There were significant changes to his gene expression. He lost collagen. His carotid artery thickened. His bones became less dense. His eye shape changed, forcing him to wear glasses. While he was in space, his performance on cognitive tests improved. But, his performance plummeted after returning to Earth, and never quite returned to pre-launch levels.

Despite all of this, Ziegler has reason to be hopeful about long-term space travel. He says the year in space study illuminated many of the challenges, and gave researchers some ideas of how to overcome them. Still, it’s probably a little early to start planning your trip to the red planet.

Watch — How a Year in Space Affects the Human Body with Dr. Michael G. Ziegler — Osher UC San Diego

Twins in Space: The Effects of Space Travel on Humans

8232Researchers love identical twins. Because they have the same genetic code, they provide a unique opportunity to determine how environment may lead to developmental differences – i.e. nature vs. nurture.

In this new program from the Stein Institute for Research on Aging, Brinda K. Rana, PhD, shares the results of NASA’s remarkable Twins Study. In March 2015, U.S. astronaut Scott Kelly embarked on a one year mission onboard the international space station. Meanwhile, his identical twin brother, Mark, remained on Earth giving scientists an opportunity to study the long-term effects of space travel on the human body versus normal development.

Ultimately, NASA wants to know what will happen to astronauts as they inch closer to their Mission to Mars. Space is a harsh environment, both physiologically and psychologically. Astronauts must contend with microgravity, disruptions in sleep cycles, radiation, and dietary limitations, as well as confined spaces and isolation from friends and family. What will happen to astronauts after 3 years – the time it will take to get them to Mars and back again?

But these studies not only have implications for the lives of astronauts. Physiologically, space travel mimics the effects of aging on the human body, changes such as cardiovascular decline, vision problems, muscle and bone atrophy, and cognitive impairment. Any discovery that improves the lives of astronauts in space could also be used to help us right here on Earth.

Learn more about what it took to plan and execute the Twins Study, as well as some of what they’re just beginning to discover. Watch Twins in Space: The Effects of Space Travel on Humans.

Browse more programs from the Stein Institute for Research on Aging.