I got my new IKEA kitchen a few months ago and I used the instructions on the IKEA oil tin to the letter as I treated the solid Oak worktops. Within a few weeks cracks and splits have appeared in the wood. Only where the sink is, in the areas that get wet a lot, but it is bloody annoying. It seems the IKEA Oil, and I suppose Danish Oil too, as the two are pretty much the same thing, is not properly water resistant. When the sufaces got wet it used to leave a water mark on the suface after it had dried. There must be some slight amount of wood stain in the IKEA Oil that washes off when it gets wet.
Today I sanded down the worktops and have used Ronseal Worktop Oil. It is entirely the same thing as Sadolin Worktop oil but has an added anti bacterial quality (silver) added. Immediately the wood repelled water, as it beaded on the surface, which it never did with the ikea oil. I have only applied one coat so far and will apply 2 or three more, but it already looks great. Its a clear Oil and leaves the wood with a slight sheen.
I will never use anything else again. I love my IKEA Kitchen though, just the Worktop Oil is rubbish.