It affects everyone Rich, its a drug. Most common side effect is you cant sleep properly, thats why these Red Bull drinks work so well, they are full of Caffeine. Most manufacturers use it to addict you to their product. Coffee, Coke chocolate anyone?

Sadly, most people have no idea that problems they have in life, especially depression, are down to normal everyday chemicals like this, so they can easily say "Im not affected" but in reality, unless you give it up, its hard to say. A lot of clinically proven manic depressents have been cured by releae from caffeine addiction. They didnt think that coffee affected them either, most of them loved it so much they "Couldnt get started in the morning without one" Come on people, it would sound better coming from a heroin addict!