Forget apples.  According to this article (click here to read it), a study in Oregon indicates that moderate alcohol consumption may boost your immune system. The general gist is that consuming alcohol at a level where you can't drive legally depresses your immune system (no surprise there), and moderate alcohol consumption helps your immune system more than if you had none at all. After reading this article, I have two comments:

1.  Take your health care into your own hands and have a cocktail!
2.  You have to love a scientific study that involves drinking monkeys.