Specific Purpose: To inform my audience about the history of caffeine, how the body processes caffeine, and possible side effects of excessive caffeine consumption. Central Idea: Caffeine has been around for centuries and has been used for it energizing effects on the body . Introduction
I. It’s the night before your chemistry exam and you decide to learn three weeks worth of material in one night. II. When 1:30 comes around and you can feel your eyes starting to get heavy, what do you grab to give you that extra energy to keep going? Is it coffee? Is it a Red Bull? III. Why do these types of drinks help us keep our eyes open long enough to get through that last chapter on combustion reactions? IV. The answer is caffeine.
V. As college students, most of us consume caffeine every single day, so today I am going to share with you the history of caffeine, how the body processes caffeine, and possible side effects from excessive caffeine consumption. (Transition: Before I get into the many affects of caffeine on the body, lets go back in time to see where caffeine came from.)
I. The appreciation of caffeinated beverages dates back tens of thousands of years. a. What is caffeine anyway?
i. Caffeine is a naturally occurring substance that forms as an end product of nitrogen metabolism in plants. ii. It is found in more than 60 different plants species around the world, including coffee beans, tea leaves, and coco beans. b. The wild coffee bean plant originated in Ethiopia and according to Reginald Smith, author of the book A History of Coffee, cultivation of caffeine containing food and beverages from the coffee bean may have begun as early as AD575.” c. Centuries passed before coffee would reach Europe by the 17th century, but then spread uncontrollably to all parts of the world, including America. d. Coffee was brought to America in the mid 1600s.
i. At this time, most Americans still preferred to drink tea, another caffeinated beverage, even though coffee houses were being built all over the country. ii. Coffee did not become America’s favorite beverage until the Boston Tea Party, when Americans revolted against Britain’s heavy tax on tea. (Transition: Now that you know where coffee came from, lets look at how the body processes it.) II. How does that morning cup of coffee wake you up and give you that added energy to get the day started? a. Well, caffeine is known to boost the effects of neurotransmitters, such as dopamine, and serotonin. i. For example, dopamine is a neurotransmitter known to affect concentration. ii. Dopamine is also responsible for signaling your brain when it is time to go to bed, but when caffeine is introduced to the body, this signal is blocked. b. Caffeine also causes your body to release more adrenaline, which causes faster heart beat, more blood being pumped to muscles and organs in your body, and adrenaline tells your liver to release sugar into the blood stream. c. When caffeine is in the blood stream, it encourages the release of more calcium ions, which in turn causes muscle to contract faster. d. The professor of nutrition at Tufts University, Susan Roberts, says that, “Research studies broadly document favorable changes such as increases in metabolic rate, increased fat oxidation, and a perception of increased physical and mental energy.” i. With all of these energy-boosting effects, it’s easy to see why we love caffeine so much. ii. Even though caffeine can make us feel invincible, consuming too much can have negative effects on our health. (Transition: Lets take a look at how much caffeine we should be consuming and what could happen if we consume too much.) III. Many people don’t know, but there are negative side effects of the overuse of caffeine. a. According to the article “Selected Health and Behavioral Effects Related to the Use of Caffeine” published in the Journal of Community Health, “Over 80% of adults consume caffeine daily in the form of coffee, tea, or soft drinks.” i. Since we consume caffeine daily, the amount we consume is important. ii. J.J Barone, author of “Caffeine Consumption”, which was published in the book Food and Chemical Toxicology, states that people should only consume 5 oz. of ground roast coffee, 5 oz. of tea, and 6 oz. of cola only a daily basis. iii. For a lot of people, this is not enough caffeine to feel the energizing side effects, which leads to overconsumption. b. The many side effects of the overconsumption of caffeine include insomnia, nervousness, restlessness, irritability, dizziness, nausea, fast heartbeat, and muscle tremors. i. Caffeine interferes with your body’s internal signal that it is time for bed. So, caffeine causes sleep loss and decrease in quality of sleep, which in turn contributes most of the negative side effects. ii. These negative side effects can easily be stopped when the person returns to a normal routine. Conclusion
I. Today we have learned where caffeine originated, how it affects the body, and side effects of overconsumption of caffeine. II. Next time you grab a cup of coffee, weather it be to wake up in the morning or so you can pull an all-nighter, thank the Ethiopians, I know I will. III. Thank you for listening.