Caffeine is a wonderful thing and I enjoy copious amounts of it every day. Have you ever wondered what it is, how it works, why its addictive and how to tame it? neither have I really, but this article is interesting anyway. Go check it out.
Effectiveness, Tolerance, and Headaches
Why do so many patients coming out of anesthesia after major surgery feel a headache? It’s because, in most cases, they’re not used to going so long without coffee. The good news? If they wait a few more days, they can start saving coffee again for when they really need it.
The effectiveness of caffeine varies significantly from person to person, due to genetics and other factors in play. The average half-life of caffeine—that is, how long it takes for half of an ingested dose to wear off—is about five to six hours in a human body. Women taking oral birth control require about twice as long to process caffeine. Women between the ovulation and beginning of menstruation see a similar, if less severe, extended half-life. For regular smokers, caffeine takes half as long to process—which, in some ways, explains why smokers often drink more coffee and feel more agitated and anxious, because they’re unaware of how their bodies work without cigarettes.
and a video with MRI evidence of caffeine’s effect on the brain.