My personal experience was that frozen caster oil was harsh on my body in comparison with the frozen cod liver oil. I took the frozen cod liver oil approx. every other day for months, until I was no longer getting out parasites.
Cod liver oil is good for you. I take it unfrozen almost every day to meet my need for fish oil/omega 3's. I find that 6 capsules (unfrozen) a day combined with a large dose of Vit D eliminates my depression.
Our brains are made mostly of fat and we need to continually feed our brain good fats.
I don't think much of the cod liver oil is absorbed when it is frozen. It seems to pass out and create a yellow ring in my toilet. That's the only problem I have with it but it sure is effective in smothering those parasites. Lubricates the anus too so they slide out easily.