Which will keep you more awake - Tea or Coffee?

Factual Questions
1

I’ve heard that tea has more caffine than coffee but then why is coffee typically used to keep you awake? Does coffee have more energy value or something? Which is more effective tea or coffee?

2

I don’t know where you heard that teas have more caffeine than coffee, but that is wrong:



**8-ounce Beverage			milligrams**
Coffee, Drip				115-175
Coffee, Brewed 				80-135
Coffee, Espresso (2 ounces)		100
Coffee, Instant 			65-100
Tea, iced 				47
Tea, brewed, imported brands (avg.)	60
Tea, brewed, U.S. brands (avg.)		40
Tea, instant 				30
Tea, green 				15
Hot cocoa				14
Coffee, Decaf, brewed 			3-4
Coffee, Decaf, instant 			2-3

From here.

3

I believe the confusion comes in due to the fact that tea has more caffeine before being brewed. But in the finished beverage, coffee has more caffeine.

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