Kidney stones are prevalent not on earth alone, but also in space! Astronauts fall an easy prey to kidney stones probably due to the restricted diet they follow. Researchers at University of Minnesota reveal that at least 14 American astronauts have developed kidney stones in the last 5 years. Occurrence of kidney stones, when the time spent in space is long, can be a major health concern.



Further Research at the University of Minnesota has concluded that regular exercise is one way to ensure prevention of kidney stones among astronauts. In fact it is the only way to reduce the risk of kidney stones in space. This particular study was funded by the National Aeronautical and Space Administration and the National Institutes of Health.

Exercise stimulates gravity and helps astronauts to fight loss of calcium from bones. Because of the zero-gravity environment in space, the calcium loss and loss of strength from muscles takes place. This lost calcium makes its way to the kidneys where it may end up in the form of kidney stones.

Astronauts have been exercising in space to maintain their health. However, it is impossible to keep to their pre-flight fitness levels. Manoj Monga, Professor of urologic surgery and lead investigator stated that with extending time in space, kidney stone threat was a serious concern, which could even lead to aborting of a mission. The study was published in the July issue of The Journal of Urology.

Identical twins were taken as subjects to take into account the genetic factor in kidney stone development. The twins were made to lie in beds tilted in a way so that their heads would be lower than their feet. This was done to stimulate low gravity for 30 days. One twin per pair was selected to exercise regularly in a chamber that put resistance on their bodies. The pressure was equivalent to what one feels while running on earth. The other twins in the pairs were used as non-exercising controls.

It was found that the non-exercising group of subjects had higher levels of urinary calcium than the exercising group. Thus, astronauts who follow a regular exercise regimen are at a lesser risk of developing kidney stones. Astronauts tend to drink lesser water and are on high sodium diets. Exercising is a great way to avoid kidney stones and staying fit!