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How long does caffeine actually stay in your system?
A straightforward answer, plus why the six hour half-life number you have seen everywhere does not tell the whole story.
Read →Jitters and anxiety
Why do I feel anxious after drinking coffee?
Feeling jittery, anxious, or on edge after coffee is not just in your head. Here is what is actually happening in your body, and what to do about it.
Read →Sleep
Why can't I sleep even though I stopped caffeine at 2pm?
The no-caffeine-after-2pm rule does not work for everyone, and there is a real reason why.
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