Duckweed is an incredible, radiation-fighting astronaut food – and by changing how it is grown, we made it better

Duckweed is a small floating plant that grows on the surface of ponds. It is commonly eaten in Asia but is mostly considered a pest plant in the U.S. as it can quickly take over ponds.

But duckweed is a remarkable plant. It is one of the fastest-growing plants on Earth, is the most protein–dense plant on the planet and also produces an abundance of important micronutrients.

Two of these micronutrients are the inflammation-fighting antioxidants zeaxanthin and lutein. Zeaxanthin is the more potent of the two, but is hard to get from most leafy greens since fast-growing plants accumulate zeaxanthin only under extremely bright lights.

Due to the ionizing radiation in space, astronauts are susceptible to chronic inflammation and diseases caused by cellular oxidation. Zeaxanthin and lutein have been shown to fight radiation damage as well as eye disease, another common health problem that astronauts experience.

Many essential micronutrients have a finite shelf life – often only a few months. As astronauts begin going on longer missions, the only way they will be able to get these antioxidants is to grow them on board.