They used it for both and as a source of vitamin A and whatever other nutrients are in it. They used it for everything. There is an episode of I Love Lucy where a recipe for homemade baby formula is described which includes cod liver oil.
In a lot of things it was pretty good at what they used it for though, that does continue to be true.
In a lot of things it was pretty good at what they used it for though, that does continue to be true.