RESEARCHERS IN THE NETHERLANDS ARE EXPLORING A POTENTIAL LINK BETWEEN A DEFICIENCY IN VITAMIN K — FOUND IN HIGH LEVELS IN SOME CHEESES AND LEAFY GREENS — AND DEATH FROM COVID-19.

Dutch scientists are exploring a potential link between a deficiency in vitamin K, which is found in high levels in some cheeses, leafy greens and Japanese natto, and death from COVID-19.

In a recent study, researchers found that many patients who had either died from the disease or were treated for it at Nijmegen’s Canisius Wilhelmina hospital in the Netherlands had insufficient levels of vitamin K, The Guardian reports.

The researchers are now seeking funding for a clinical trial.

In collaboration with the Cardiovascular Research Institute Maastricht, the scientists studied 134 people with COVID-19 who were admitted to the hospital between March 12 and April 11, and a control group of 184 patients who had tested negative for the disease.

An important factor in bone and heart health, according to the Harvard T.H. Chan School of Public Health, vitamin K plays a role in making the proteins required to control blood clotting. Crucially, blood clots — which can cause strokes, heart attacks and other life-threatening conditions — are increasingly being found in people with COVID-19.

The fat-soluble vitamin takes two forms: vitamin K1 (phylloquinone) and vitamin K2 (menaquinone). “K1 is in spinach, broccoli, green vegetables, blueberries, all types of fruit and vegetables,” Rob Janssen, a scientist involved in the project, told The Guardian. “K2 is better absorbed by the body. It is in Dutch cheese, I have to say, and French cheese as well.”

Considering their initial findings, he added that even if it turns out that vitamin K doesn’t play a role in fighting COVID-19, people — with the exception of those taking blood thinners — would benefit from maintaining a healthy level nonetheless. “We are in a terrible, horrible situation in the world. We do have an intervention which does not have any side effects, even less than a placebo. There is one major exception: people on anti-clotting medication. It is completely safe in other people,” Janssen said.

Along with some cheeses — such as Gouda, Edam, Jarlsberg, Münster, Cheddar and Stilton, and eggs and meat, natto (a fermented Japanese food made from soybeans) is among the best sources of vitamin K2.

The health benefits of eating natto especially warrant further study, Janssen told The Guardian. “I have worked with a Japanese scientist in London and she said it was remarkable that in the regions in Japan where they eat a lot of natto, there is not a single person to die of COVID-19; so that is something to dive into, I would say.”