Caffeine is the world’s the most popular mood-alterning drug. It also one of the oldest, as man has been brewing beverages from caffeine-based plants since the Stone Age. Today it is commonly found in coffee, tea, soft drinks, chocolate and a wide variety of over-the-counter medications, it is legal to buy and easily accessible.
How it Works:
Caffeine is a physically addictive drug and how it works is by fooling your body into thinking it isn’t tired. When your brain is tired it releases a chemical called adenosine. Caffeine mimics this chemical so it plugs up the receptors and prevents the adenosine from getting absorbed by your brain. So your brain does not receive the chemical signals to slow down and continues to build up the stimulants.
There are some good and bad effects from using caffeine:
Good: It temporarily increases alertness, comprehension, memory, refleces and rate of learning and increase clarity of thought.
Bad: “Too much caffeine can cause hand tremors, loss of coordination or appetite, insomnia, and in extreme cases, trembling, nausea, heart palpitations, and diarrhea.
Widely varying the amount of caffeine you ingest can put a strain on your liver, pancreas, heart, and nervous system. And if you’re prone to ulcers, caffeine can make your situation worse.
If you manage to consume the equivalent of 70 – 100 cups of coffee in one sitting, you’ll experience convulsions, and may even die.”
Information from http://www.neatorama.com/2007/09/24/caffeine-facts/