Question

What kind of research has been conducted regarding calcium depletion and human spaceflight?

Much research has been done to examine the effects of space flight on the skeletal system, particularly calcium depletion and the resulting physical problems. While most experiments have been performed on rats, most notably by Dr. Emily Morey-Holton at NASA Ames Research Center, the findings are applicable to human physiology as well. (For a recent article on spaceflight and bone loss, please see http://nai.arc.nasa.gov/index.cfm?page=space_bones)

Microgravity is generally believed to be the chief cause of calcium depletion. During spaceflight, weight-bearing bones are no longer needed for the support they served in earth gravity. They soon undergo demineralization to share calcium with the rest of the body (calcium is essential for neuronal and immune function as well).

Demineralization and its effects are well-identified phenomena, but scientists are still working to learn how to circumvent the problem. The most immediate solution is artificially-induced gravity produced by a spinning spacecraft. However, such a spacecraft presents large technical and financial hurdles in itself, and researchers are eagerly exploring alternate methods to keep the body from expunging its skeletal system of the minerals that comprise it. Other proposed solutions have included electrostimulation and administration of bone growth hormones.
October 29, 2001