Quote Originally Posted by MadMojoMonkey View Post
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You're forgetting the other criteria for banned substances: there's the Performance Enhancing aspect and there's the undue harm aspect. Eating a good balanced diet is a performance enhancing entity, but it's not banned because eating a good balanced diet is good for you.

The idea is that if they came up with a drug that makes you so fit that there is no way that anyone not taking that drug could keep up with you, but this drug has the nasty side effect of killing you by the age of 35, then allowing for that drug to be taken will quickly make it so that people not willing to die by the age of 35 will be completely out of contention. This is an extreme example, obviously, but they don't want people blood doping because there are serious heart and other circulatory-system-related risks in doing these things that are linked to a reduced life expectancy.

Even in your analogy, caffeine is in fact a banned substance. Or I should say that taking so much caffeine that it does undue harm to your health is banned (eg: caffeine pills).