Spaceflight bone loss reshapes osteoporosis treatment on Earth
Astronauts on the ISS lose 1-2% of bone mineral density per month due to microgravity, so a six‑month mission can erase roughly a year’s worth of bone mass for a postmenopausal person. NASA’s countermeasures—ARED-based resistance exercise, cardio, and, in some cases, alendronate—partially slow the loss but do not prevent it, and recovery after return remains incomplete, effectively aging skeletal health by about a decade for longer missions. These findings are driving terrestrial osteoporosis research and potential treatments, though transfer to Earth is not direct and requires clinical adaptation.
