Hi! Please check out my articles on Wholistique. I talk about the things I've tried and give links to the research.

In summary though - tell your Dad to supplement with DHA (I provide links in one of my articles), try fasting, and make sure to only eat pure foods. That means all organic. If he eats animal products, only pasture raised.

Feel free to ask me questions after you've read the articles. And good wishes for your father!