Space-grown lettuces space-grown was similar in composition to Earth-grown control samples, while some plants were even richer in a number of elements, including potassium, sodium and zinc.
The experiment involved crops being grown in individual sealed units of ceramic soil under red LED lighting for 33 to 56 days.
Gio Massa, who led the lettuce-growing project, said: “I think plants are going to be very important for the crew diet in the future and if we ever want to be Earth-independent.
“If you store packaged food for a long duration the quality, flavour and nutritional quality decrease, the vitamins degrade,” she said. “We can’t guarantee that they’re going to get enough nutrition right now.”
She added: “There may also be psychological benefits of growing plants and looking after plants.”
The scientists tested both lettuces in similar environments and were “surprised” to find how nutritious space grown lettuce was.
Although the lettuce did have higher levels of bacteria, the crops were not found to carry any dangerous bacteria such as E.coli or salmonella.
At present, astronauts receive their food through regular rocket shipments from Earth, but when they go on longer missions the nutrients in the food breaks down.
It is believed that the ability to successfully grow food in space could be crucial for long-duration interstellar missions, such as Nasa's first crewed mission to Mars - scheduled to depart within the next decade.
Additional reporting by Press Association
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