Caffeine blocks receptor sites in the brain where the sleep hormone usually fits. Long term caffeine use leads to the brain creating more receptor sites. Withdraw caffeine suddenly, the brain gets sleep message overload, with all the crankiness that entails. Some studies say caffeine bad, some say caffeine good; unless there's a health problem from caffeine intake, I say why give it up?

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If the theory does not conform to the facts, then the facts must be discarded.

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