Astronauts improve bone density in space flight—exercise and good nutrition are key
by Newsletter Editor
Astronauts typically lose one to two percent of bone density per month compared to earthbound older adults who may lose this amount in a year, doctors said. Normal bones constantly leach and reabsorb minerals, in a process called “remodeling,” but in space, bones lose minerals without replacing them, causing loss of bone density.
In one study, astronauts used an advanced exercise device permitting up to 600 pounds simulated weight resistance, and consumed sufficient calories and vitamin D. Compared to a 2006 study that used exercise equipment that was half as powerful, and no nutritional controls, astronauts came home with more lean muscle, less fat, and retained more whole-body and bone-specific mineral density.
According to Dr. Scott M. Smith, NASA nutritionist, “After 51 years of human spaceflight, these data mark the first significant progress in protecting bone through diet and exercise.”