Astronauts Experience Bone Loss in Space, Experts Explain How It Happens

Humans lose bone as they age, sustain injuries, or in any situation where their bodies are immobile.

However, but very little is known about what actually occurs to astronauts or how they recover. Studying them enables us to observe the bodily processes taking place in such a brief period of time.

On Earth, it would take years of observation to observe the same rate of bone loss.

Astronaut Bone loss

(Photo : GREGG NEWTON/AFP via Getty Images)

The McCaig Institute for Bone and Joint Health's director and professor at the Cumming School of Medicine, Dr. Steven Boyd, Ph.D., launched the TBone study in 2015, as per ScienceDaily.

To determine whether bone heals after long-duration spaceflight, the study followed 17 astronauts before and after their trips into space over the course of seven years.

According to Dr. Leigh Gabel, Ph.D., assistant professor of kinesiology and lead author of the study, bone loss occurs in humans as we age, sustain injuries, or in any situation in which we are unable to move our bodies.

The researchers flew to Houston, Texas' Johnson Space Center to scan the astronauts' wrists and ankles before they launched into space, after returning to Earth, and at six and twelve months.

This loss occurs as a result of the fact that in microgravity, bones like your legs that would typically support your weight on Earth are not required to do so; instead, you float.

Particularly in comparison to astronauts who flew for longer periods of time, some astronauts who flew shorter quests, under six months, managed to recover bone strength and density in the lower body.

The study's next iterative process will examine the effects of even long journeys to sustain astronauts who may someday travel far beyond the International Space Station as future space missions start exploring travel to much more distant locations.

Read More: Lettuce Grown in Space May Help Astronauts Deal with Bone Loss Issues

Concerns to Astronauts' bone loss

Long-duration spaceflight causes bone loss in astronauts.

This study is novel in that experts tracked astronauts for a while after their space flight to determine whether and how bone recovered, according to skynews.

In order to stop bone loss, space agencies must enhance defenses like exercise and diet, Professor Gabel cautioned.

The study discovered that in-flight exercise, such as resistance training on the ISS, was essential in preventing muscle and bone loss.

In comparison to their typical exercise routine on Earth, astronauts who performed more deadlifts were much more likely to recover bone after such a mission.

The tibia in the lower leg of the astronauts lost a total of 2.1% less density and 1.3% less bone strength.

Good bone structures thin out during spaceflight, and eventually, a few of the bone rods become disconnected from one another, according to Professor Gabel.

The astronaut's general bone structure is permanently altered by the space flight because the disconnected bone connections cannot be rebuilt after the astronaut returns to Earth.

The cardiovascular system also was impacted by spaceflight, according to research.

The cardiovascular system and vision may be impacted because astronauts encounter a fluid shift that causes more blood to pool in the upper body in the absence of gravity, according to Professor Gabel.

Concerns about radiation include the fact that astronauts will be exposed to more sunlight and have an increased risk of developing cancer and the farther they travel from Earth.

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