Though lettuce and other leafy salad vegetables are crucial parts of a balanced diet, a literal "rocket salad" may not be the healthiest choice for astronauts aboard the International Space Station (ISS).
New research has shown that microgravity, the condition in which ISS astronauts live, can make lettuce more vulnerable to pathogens — organisms that can sometimes lead to the outbreak of foodborne illnesses. The research could have a pretty big influence on future crewed space missions to the moon and, eventually, to Mars.
Currently, ISS crew members can eat salad greens that have been grown on the space station in temperature, water and light-controlled chambers. They can also eat items sent to orbit from Earth. However, the ISS has been known to host a lot of pathogens, like bacteria and fungi, that can cause disease. And if some of these pathogens, like E. coli and salmonella, colonize the tissue of eaten lettuce, the consumer can get sick.
