New Study Shows Bone Loss in Space Can Be Permanent
2022-07-12
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1A recent study about bone loss in astronauts is providing important information about the effects of space travel on the human body.
2The research could help space agencies reduce harmful effects on astronauts in future space flights.
3The recent research gathered new data on bone loss in 17 astronauts who worked on the International Space station.
4It involved 14 male and three female astronauts. Their average age was 47 years old.
5The study looked at bone loss caused by the microgravity conditions, or very weak force of gravity, in space.
6It also studied how bone mineral density can be regained back on Earth.
7The astronaut's missions were about five and one half months on average.
8One year after returning to Earth, the astronauts had 2.1 percent reduced bone mineral density at the tibia, a bone in the leg.
9They also had on average a 1.3 percent reduction in strength.
10Nine experienced permanent loss - they did not fully recover bone mineral density after the space flight.
11Leigh Gabel of the University of Calgary was the lead writer of the research published recently in Scientific Reports.
12Gabel said that what is new about this study "is that we followed astronauts for one year after their space travel to understand if and how bone recovers."
13Gable noted that astronauts experienced bone loss during six-month spaceflights that one would expect to see in older people over 20 years on Earth.
14These astronauts "only recovered about half of that loss after one year back on Earth," she added.
15The bone loss happens because bones that usually carry weight on Earth do not carry weight in space.
16Space agencies are going to need to make better exercise and eating plans to help prevent bone loss, Gabel explained.
17She noted that "During spaceflight, fine bone structures thin, and eventually some of the bone rods disconnect from one another."
18The result, Gabel said, is that "once the astronaut comes back to Earth, the remaining bone connections can thicken and strengthen,
19but the ones that disconnected in space can't be rebuilt, so the astronaut's overall bone structure permanently changes."
20The study's astronauts flew on the space station in the past seven years.
21The astronauts were from the U.S. space agency NASA, Canadian Space Agency, European Space Agency and Japan Aerospace Exploration Agency.
22The effects of space travel on the human body are important for space agencies as they plan new explorations.
23NASA is aiming to send astronauts back to the moon, a mission now planned for 2025 at the earliest.
24Future astronaut missions to Mars or a long-term presence on the Moon's surface are also possibilities.
25Gabel said that muscle loss, bone loss, effects on the cardiovascular system, and even radiation are big concerns for astronauts.
26"Without gravity pulling blood towards our feet, astronauts experience a fluid shift that causes more blood to pool in the upper body.
27This can affect the cardiovascular system and vision," Gabel explained.
28She added that "Radiation is also a large health concern for astronauts as the further they travel from Earth the greater exposure to the sun's radiation and increased cancer risk."
29The study showed that longer space missions resulted both in more bone loss and a lower likelihood of recovering bone later.
30In-flight exercise, such as resistance training, proved important for preventing muscle and bone loss.
31Astronauts who performed more deadlifts compared to what they usually did on Earth were found to be more likely to recover bone after the mission.
32Gabel said there is still much to be learned about the effects of space travel on human health - particularly on space missions longer than six months.
33I'm John Russell.
1A recent study about bone loss in astronauts is providing important information about the effects of space travel on the human body. 2The research could help space agencies reduce harmful effects on astronauts in future space flights. 3The recent research gathered new data on bone loss in 17 astronauts who worked on the International Space station. 4It involved 14 male and three female astronauts. Their average age was 47 years old. 5The study looked at bone loss caused by the microgravity conditions, or very weak force of gravity, in space. It also studied how bone mineral density can be regained back on Earth. 6The astronaut's missions were about five and one half months on average. 7One year after returning to Earth, the astronauts had 2.1 percent reduced bone mineral density at the tibia, a bone in the leg. They also had on average a 1.3 percent reduction in strength. Nine experienced permanent loss - they did not fully recover bone mineral density after the space flight. 8Leigh Gabel of the University of Calgary was the lead writer of the research published recently in Scientific Reports. 9Gabel said that what is new about this study "is that we followed astronauts for one year after their space travel to understand if and how bone recovers." 10Gable noted that astronauts experienced bone loss during six-month spaceflights that one would expect to see in older people over 20 years on Earth. 11These astronauts "only recovered about half of that loss after one year back on Earth," she added. 12The bone loss happens because bones that usually carry weight on Earth do not carry weight in space. Space agencies are going to need to make better exercise and eating plans to help prevent bone loss, Gabel explained. 13She noted that "During spaceflight, fine bone structures thin, and eventually some of the bone rods disconnect from one another." 14The result, Gabel said, is that "once the astronaut comes back to Earth, the remaining bone connections can thicken and strengthen, but the ones that disconnected in space can't be rebuilt, so the astronaut's overall bone structure permanently changes." 15The study's astronauts flew on the space station in the past seven years. The astronauts were from the U.S. space agency NASA, Canadian Space Agency, European Space Agency and Japan Aerospace Exploration Agency. 16The effects of space travel on the human body are important for space agencies as they plan new explorations. 17NASA is aiming to send astronauts back to the moon, a mission now planned for 2025 at the earliest. Future astronaut missions to Mars or a long-term presence on the Moon's surface are also possibilities. 18Gabel said that muscle loss, bone loss, effects on the cardiovascular system, and even radiation are big concerns for astronauts. 19"Without gravity pulling blood towards our feet, astronauts experience a fluid shift that causes more blood to pool in the upper body. This can affect the cardiovascular system and vision," Gabel explained. 20She added that "Radiation is also a large health concern for astronauts as the further they travel from Earth the greater exposure to the sun's radiation and increased cancer risk." 21The study showed that longer space missions resulted both in more bone loss and a lower likelihood of recovering bone later. In-flight exercise, such as resistance training, proved important for preventing muscle and bone loss. Astronauts who performed more deadlifts compared to what they usually did on Earth were found to be more likely to recover bone after the mission. 22Gabel said there is still much to be learned about the effects of space travel on human health - particularly on space missions longer than six months. 23I'm John Russell. 24Will Dunham reported on this story for Reuters. John Russell adapted it for VOA Learning English. 25____________________________________________________________________ 26Words in This Story 27microgravity - n. very weak gravity 28mission -n. a flight by an aircraft or spacecraft to perform a specific task 29cardiovascular system - n. of or relating to the heart and blood vessel system of the body 30deadlift - n. a lift in which the weight is lifted from the floor 31____________________________________________________________________ 32We want to hear from you. We have a new comment system. Here is how it works: 33Each time you return to comment on the Learning English site, you can use your account and see your comments and replies to them. Our comment policy is here.