I am confused about it also. I read that the DHA in fish oil was supposed to help my memory problems caused by years of taking Topamax, but the capsules I was taking only had so much in them, so I asked my pdoc about straight DHA, and his reply was, "What is that?" Not very helpful. I told him it was a vitamin supplement and what I wanted to take it for (we have discussed my memory problems before with no satisfactory answer), all he said was it shouldn't interfere with my other meds. So I take the recommended dose of 900 mg a day. Seems to be helping a little.