I think if your diet is consisting of a lot of whole fresh vegetables/fruits and grass fed meats that will give you the most bang for your buck. If you feel you are deficient in certain vitamins and minerals than try to find a good multivitamin that is preferably made from whole foods without artificial coloring and ingredients (stay away from vitamins like Centrum). I prefer eating fatty fish a few times a week over fish oil, but I keep a bottle of fish oil on hand just in case I eat out and the meat in conventionally raised.
"If man made it, don't eat it" - Jack Lallane
People say I am on a "crazy" diet. What is so crazy about eating veggies, fruits, seafood and organ meats? Just because I don't eat whole wheat and processed food doesn't make my diet "crazy". Maybe everyone else with a SAD are the "crazy" ones for putting that junk in their system.