Fun fact: In Northern Europe there is very little sunlight, not enough for the body to be able to produce vitamin D with it. This leads to rickets, and much of Northern Europe had a huge problem with the illness, with many of their children having horrible stunted growth and deformities.

Vikings, however, did not have this issue. Vikings figured out that something inside cod liver stops rickets, and would extract juice from the liver to drink while on voyages, and they had traditions that involved consuming the livers of cod fish. This is because cod liver is LOADED with vitamin D.

So really this video is just the old school way of getting your vitamin D