MONDAY, Nov. 8 (HealthDay News) -- Because weightlessness during
space flight can cause people to experience rapid bone loss, long
missions may take a toll on crew members' bones, according to
In a new study, lead investigator Dr. Shreyasee Amin, an
associate professor at the Mayo Clinic, and colleagues analyzed
bone mineral density (BMD) measurements in 28 U.S. space crew
members (24 males, four females) whose space missions ranged from
95 to 215 days. BMD is an indicator of bone strength.
All 28 crew members had their BMD measured before their space
flight and within 33 days after their return to Earth. In addition,
24 members of the group had their BMD checked again between six and
18 months after returning from space.
BMD measurements were taken for the total body, the hip, the
lumbar area of the spine, and two sites at the wrist. The crew
members' BMD results were compared with healthy adults who had
never left Earth.
The astronauts' BMD immediately after space flight was much
lower than normal and consistent with what is known about bone loss
during space flight, said the researchers. But, the investigators
also found that about 12 months after crew members returned from
space, BMD at several locations was still lower than normal.
The findings indicate that an extended period in a low-gravity
environment could have a long-term harmful effect on bone
The study is scheduled for presentation Nov. 9 at the annual
scientific meeting of the American College of Rheumatology (ACR),
held in Atlanta.
"Ideally, we need to identify better strategies to prevent the bone loss that occurs during space flight so that we can keep the bones of those serving on long-duration space missions healthy and strong for the long-term," Amin said in an ACR news release.
NASA has more about
bones and space travel.