Ethan Avery


Intro and History

Caffeine (C8H10N4O2) was first consumed in Asia as tea over 5000 years ago, then in North America as coffee 1000 years ago. Since these drinks began to be brewed they have been spread around the world. Caffeine despite being used for thousands of years was only isolated in 1819 by Friedrich Ferdinand Runge. Caffeine in it’s raw state is a bitter, white powder. The bitter flavor has lead to it being used to flavor many things. [3]



The first thing caffeine does is why plants produce caffeine at all. The caffeine causes bugs that are trying feed on plants to be paralyzed. Caffeine is really toxic to many insects, fungi and bacteria. However this is because much smaller amounts are required to kill a bug than are required to kill a human.[7]
Caffeine in humans causes stimulation of the central nervous system, heart rate and breathing, along with psychotropic (mood changing effects). It is believed that caffeine works by blocking the adenosine receptors in the brain. The neurotransmitter adenosine, by crossing the synapses between brain cells, tells the body to slow down cellular activity, in particular the extraction of energy from sugar. The adenosine isn’t stopped from being released. Instead the caffeine attaches itself to the receptor and so the adenosine message is never passed on.[3]
Also without the adenosine the cells will instead release adrenaline. The adrenaline causes an increase in heart rate, breathing and blood flow to the muscles, and decrease of blood flow to the vital organs, which causes the liver to release glucose and with more sugar comes even more energy. [3]
It is also believed that caffeine causes a release of dopamine, which is a neurotransmitter that causes happiness.[7]



One recent study has found that people who have caffeine before working late at night make fewer mistakes while working. The study showed that 13 out of 20 people had higher performance with caffeine than without caffeine. [2]
Another study shows that addiction to caffeine isn’t really addiction, like to illegal drugs. It’s something that could be easily shaken, though people do develop a dependence on caffeine it’s not the same as addiction [6]
Another study shows that there are many health benefits to some caffeinated drinks, particularly tea and coffee. Apparently they have antioxidants that help to fight cancer and improve heart health. [6]


A new study has found that people who are dependent on caffeine are no longer receiving the benefits of an increased attention span but instead have reached a sort of equilibrium where they will just have a normal energy level when they have caffeine. [5]
Caffeine tends to have worse and lasting affect on children, which varies from aggravating existing heart conditions to permanently affecting some children’s attention spans. [1]
While some studies say that caffeine doesn’t cause addiction, others do. Some studies show that caffeine slows the breakdown of an enzyme called phosphodiesterase which leads to an increase in another enzyme that causes addiction. [7]

  1. "Caffeine and Your Child." KidsHealth - the Web's Most Visited Site about Children's Health. Web. 04 June 2010.
  2. "Caffeine Reduces On-the-Job Mistakes." WebMD - Better Information. Better Health. Web. 04 June 2010.
  3. Helmenstine, Anne Marie. "Caffeine Chemistry." Chemistry - Periodic Table, Chemistry Projects, and Chemistry Homework Help. Web. 04 June 2010.
  4. "Study's Wake-Up Call for Coffee: It Doesn't Make You More Alert - AOL News." Top News and Analysis From AOL News. Web. 04 June 2010.
  5. "T_Articles." Asian Food Information Centre (AFIC). Web. 05 June 2010. < and FACTS about Caffeine.htm>.
  6. "Why Plants Make Caffeine - The Naked Scientists 2005.03.02." The Naked Scientists Online, Science Podcast and Science Radio Show. Web. 03 June 2010.