Drinking water possessing new functional properties will protect space crews from radiation during long space flights, including a mission to Mars, as follows from a report to the 17th Conference on Space Biology and Medicine, underway in Moscow on Monday.

"Drinking water with new functional properties will hold special place in the system of increasing cosmonauts’ resistibility to radiation. Of great interest is light isotope water and water with controlled and optimized mineral composition," the conference’s report says.

Special attention must be paid to preventing water preservatives, including silver ions, from getting into the cosmonaut’s body. Silver is a heavy metal, and heavy metals increase the harmful effects of ionizing radiation.

Also, scientists suggest cosmonauts should sleep in special water-filled bags.

"For instance, one might consider the feasibility of using sleeping bags filled with water mixed with gel or polyethylene granules. Water and polyethylene contain light elements, including hydrogen. Both provide effective protection from neutrons, both primary and secondary ones," the report says.