How long does caffeine stay in your system?
It depends on several things which can include
Up to 99% of natural caffeine is absorbed within 45 minutes.
It passes through the blood brain barrier, placenta, and into breast milk, as well as all body tissues.
Then about 97% of it is metabolized by the liver into more than 25 different chemicals.
Caffeinated chemicals eliminated
Almost all of these chemicals are then eliminated from the body within 24 to 48 hours, but caffeine metabolism is faster if
and it is slower if
Tea and coffee comparison
Both tea caffeine and coffee are metabolized into theophylline but through different pathways.
Approximately 90% of North American and European adults report daily consumption of caffeinated products, with approximately 54% of Americans averaging 3 cups of coffee daily.
Other countries (approximately 5 billion people) use daily green or black tea, which is much lower in caffeine than coffee.
References for How Long Does Caffeine Stay In Your System
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This page last updated by Sharon Jones on March 4, 2013
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