I have heard it mentioned that they are seeing it almost as type 3 diabetes now. So there is a chance that diet and lifestyle can play into it, but still I guess you need the right genetic combination to trigger it as well.
I must admit I am also very similar in a conversational environment, I have trouble finding the words at times. But especially for little facts or names sometimes it can help to clench your fist when thinking, I have found this to be a useful little thing at times.