Bone Loss Similar in Astronauts, Cancer Patients

Astronauts are at risk for bone loss in much the same way that cancer patients who receive radiation therapy are, according to U.S. researchers.

Both astronauts and cancer patients are more likely to develop fractures than the general population, says Clemson University bioengineer Ted Bateman.

Recent exams of astronauts who were on the International Space Station showed signs of bone loss in the neck and vertebrae, said Bateman. Even five years after returning to Earth, they have not completely recovered from this loss.

Clemson researchers have developed the first model to study the rate of bone loss in those two groups. Bateman said microgravity and radiation from cosmic and solar sources affect the astronauts.

The study, published in the Journal of Applied Physiology, points out that unprotected astronauts could be exposed to potentially lethal doses of radiation.

Therapeutic radiation in cancer patients is an important tool for survival, but long-term effects often result in reduced bone density, fractures and back pain in both adults and children, according to the researchers.