Agreed that, if you're still eating dairy particularly, you can get all you need from food. However, sometimes it's hard because we don't eat as healthfully as we should. Additionally, I don't think it's damaging/wrong to say that vegetarians might need to pay special attention to making sure that they get certain vitamins an minerals in their diet. Iron, zinc and calcium come quickly to mind, since in the SAD they are often obtained through meat or dairy products. If you are vegan, you would probably want to check your B12 levels as well.