Paper
THE LOW DOWN ON CAFFEINE
___A Statement of the Problem
Caffeine is on trial, I am the judge. My verdict? I do not know ? but I will. I am determined to find truth, and accomplishing that task will be difficult, but very fulfilling. To determine whether caffeine is guilty of its charges, I will develop an intense experiment packed full of the scientific method. Accompanied by this experiment will be extreme background knowledge to guide me to my verdict. Strap in and enjoy the ride; here is caffeine?s story:
I grew up in an environment that was very hostile toward the compound caffeine. It was tough. I recall being in numerous situations where my buds would be sipping on a cold Mountain Dew?, or another soft drink which obtained caffeine, and I would be sipping a warm glass of V8 Juice?. That stuff is terrible, it really is. I felt isolated, for I was limited to only so many beverages, none of them that were cool either. After awhile, my ashamed secret was let out to my entire school, and for 4 years my peers ostracized me for being the ?square baby bottle boy? who could not drink the cool caffeine soda. My social life ceased to be; this forced me to deeply concentrate on the subject of caffeine and caffeine products.
I still do think about caffeine. I now question my father?s fervent belief that caffeine was a drug that chained its users into a lifetime of addiction; a tool used by greedy corporations to capture more consumers. I also question the horrible effects my dad claims caffeine has on the nervous and digestive system. I keep thinking, could this compound really be that bad?
By using the opportunity given to me by this project, I will fulfill my curiosity about caffeine and design a scientific experiment. With this experiment, I will answer the questions: 1) Does increased amounts of caffeine form dependency? 2) How does caffeine affect the speed of our bodies? 3) How does caffeine affect our system?s digestive process?
Many factors may influence this topic. My biased view which has generated from years of brainwashing by my father influence my interpretations of research and influence my hypothesis. Physiological biases may influence the way in which I shape my experiments. However I have researched and designed an experiment which reflect little to no bias by me, I have kept open minded in my quest for truth.
I am happy I chose this problem; I have learned not to blindly except the theories and ideas of my father but thoroughly investigate them myself and establish a closer truth through research and through the scientific method.
___Review of Literature
-Caffeine in its molecular form
The compound Caffeine (C8H10N4O2) is recognized by a plethora of other names, from 1,3,7-Trimethylxanthine and 1,2,3,6-tetrahydropurine to just plain No-Doz (Britannica 1999). Caffeine is a white powder substance or silky needle substance. The compound is very soluble in hot water, and when it cools, the solution deposits crystals of caffeine monohydrate (Britannica 1999). Caffeine is used as an additive in certain food products; it is a central nervous system stimulant and a diuretic (Powers SK). Caffeine is an alkaloid. There are numerous compounds called alkaloids, among them we have the methylxanthines, with three distinguished compounds: caffeine, theophylline, and theobromine, found in cola nuts, coffee, tea, cacao beans, mate and other plants. These compounds have different biochemical effects, and are present in different ratios in the different plant sources. These compounds are very similar and differ only by the presence of methyl groups in two positions of the chemical structure. They are easily oxidized to uric acid and other methyluric acids that are also similar in chemical structure (Caffeine Blues).
Caffeine is consumed very often. An average cup of coffee contains about 100 mg (.003 ounce) of caffeine. Tea also incorporates caffeine into its solution. In a 12-ounce glass of carbonated cola beverage, there is about 40 mg of caffeine (Britannica 1999). Caffeine is present in many of our beverages and foods. People probably drink a lot more than they realize.
According to the National Soft Drink Association, the following is the caffeine content in mgs per 12 oz can of soda (Caffeine Consumed Miller):
1. Afri-Cola 100.0 (?)
2. Jolt 71.2
3. Sugar-Free Mr. Pibb 58.8
4. Mountain Dew 55.0 (no caffeine in Canada)
5. Diet Mountain Dew 55.0
6. Kick citrus 54 (36mg per 8oz can, caffeine from guarana)
7. Mello Yellow 52.8
8. Surge 51.0
9. Tab 46.8
10. Battery energy drink — 140mg/l = 46.7mg/can
11. Coca-Cola 45.6
12. Diet Cola 45.6
13. Shasta Cola 44.4
14. Shasta Cherry Cola 44.4
15. Shasta Diet Cola 44.4
16. Mr. Pibb 40.8
17. OK Soda 40.5
18. Dr. Pepper 39.6
19. Pepsi Cola 37.2
20. Aspen 36.0
21. Diet Pepsi 35.4
22. RC Cola 36.0
23. Diet RC 36.0
24. Diet Rite 36.0
25. Canada Dry Cola 30.0
26. Canada Dry Diet Cola 1.2
27. 7 Up 0
By means of comparison, a 7 oz cup of coffee has the following caffeine (mg) amounts, according to Bunker and McWilliams in J. Am. Diet. 74:28-32, 1979(Caffeine Consumed Miller):
1. Drip 115-175
2. Espresso 100mg of caffeine
3. 1 serving (1.5-2oz)
4.
5. Brewed 80-135
6. Instant 65-100
7. Decaf, brewed 3-4
8. Decaf, instant 2-3
9. Tea, iced (12 ozs.) 70
10. Tea, brewed, imported 60
11. Tea, brewed, U.S. 40
12. Tea, instant 30
13. Mate 25-150mg
Other data on caffeine:
1. Cup of coffee 90-150mg
2. Instant coffee 60-80mg
3. Tea 30-70mg
4. Mate 25-150mg
5. Cola 30-45mg
6. Chocolate bar 30mg
7. Stay-awake pill 100mg
8. Vivarin 200mg
9. Cold relief tablet 30mg
Caffeine is absorbed very quickly from the gastrointestinal tract and then distributed in the various body tissues. After absorption, it passes into the central nervous system. “Caffeine sensitivity” refers to the amount of caffeine that will produce negative side effects. This amount will vary from person to person. Caffeine does not accumulate in the bloodstream nor is it stored in the body. It is excreted in the urine many hours after it has been consumed (Caffeine Blues Cherniske). Caffeine may be used as a treatment for migraine headaches and in relieving, for a short time, fatigue or drowsiness.
Caffeine may be used for medicinal reasons. Caffeine is a pharmaceutical drug. It helps blood flow to the brain in a more fluid fashion and helps prevent migraines (article 1). It improves motor performance, decreases fatigue, enhances sensory activity, and increases alertness (Britannica 1999). It also has been thought to improve endurance exercise (Endur. Powers). Caffeine will not reduce the effects of alcohol, although many people still believe a cup of coffee will “sober up” an intoxicated person (Chronic Temples). Caffeine has become very popular because of these reasons.
However, there is a down side to this drug. Caffeine intake may also produce irritability, nervousness or anxiety, jitteriness, headaches, and insomnia (Britannica 1999). Excessive caffeine intake can lead to a fast heart rate, dieresis (excessive excretion of fluids), nausea and vomiting, restlessness, anxiety, depression, tremors, and difficulty sleeping (Kids Walmer). The effect of caffeine on health has been widely studied. In particular, the effects of caffeine on fibrocystic breast disease, cardiovascular disease, birth defects, reproductive function, and behavior in children have been closely examined. A 1984 statement from the American Medical Association Council on Scientific Affairs stated, “Moderate tea or coffee drinkers probably have no concern for their health relative to their caffeine consumption provided other lifestyle habits (diet, alcohol consumption) are moderate as well.”(Chronic Temples). This statement puts caffeine use in perspective.
Caffeine increases the level of circulating fatty acids. This has been shown to increase the oxidation of these fuels, hence enhancing fat oxidation. Caffeine has been used for years by runners and endurance people to enhance fatty acid metabolism (Endur Powers). It’s particularly effective in those who are not habitual users. It does affect metabolism, though it is a good question whether its use truly makes any difference during a diet. The questionable rationale for its original inclusion in diet pills was to make a poor man’s amphetamine-like preparation from the non-stimulant sympathomimetic phenylpropanolamine and the stimulant caffeine. (That you end up with something very non-amphetamine like is neither here nor there.) The combination drugs were called “Dexatrim” or Dexa-whosis (as in Dexedrine) for a reason, namely, to assert its similarity in the minds of prospective buyers. However, caffeine has not been in OTC diet pills for many years per order of the FDA, which stated that there was no evidence of efficacy for such a combination (Endur Powers).Caffeine has been proven an effective stimulant that speeds the body up (Endur Powers). Because of all these qualities, caffeine has become very popular. Nevertheless, there a downside to using it every day, do people fool themselves into thinking that they?re not addicted to the stuff when they really are?
Caffeine is the most widely consumed behaviorally active substance in the world. Chronic caffeine intake only appears to have minor negative affects on health and that is why government regulatory agencies do not impose restrictions on it (Chronic Temples). However, some years ago it was pointed out that caffeine maybe a potential drug of abuse. Drug abuse is, in general terms, the use of an illicit substance. It?s when one craves for something so bad that they will do anything to get. They are hooked on something for the effects. The reason that they want more is because they receive withdrawal symptoms (Kids Walmer). Abrupt withdrawal of caffeine may cause headaches, drowsiness, irritability, nausea, vomiting, and other symptoms. Reduce caffeine intake will gradually to prevent any symptoms of withdrawal (Kids Walmar). In pioneering a study about withdrawal symptoms, Dreisbach and Pfeiffer (1943) observed that caffeine relieved headache withdrawal. People started relieving headaches with coffee, but then got withdrawal symptoms with coffee. In a well-controlled experiment, coffee drinkers who had been drinking coffee with caffeine for one week, preferred caffeine coffee (Caffeine Blues). Regular caffeine consumption reduces sensitivity to caffeine. When caffeine intake is reduced, the body becomes oversensitive to adenosine. In response to this oversensitiveness, blood pressure drops dramatically, causing an excess of blood in the head (though not necessarily on the brain), leading to a headache.
There is no human requirement for caffeine in the diet. Moderate caffeine intake, however, is not associated with any health risk. Three 8 oz. cups of coffee (250 milligrams of caffeine) per day is considered an average or moderate amount of caffeine. Ten 8 oz. cups of coffee per day is considered excessive intake of caffeine (Kids Walmar).
A child’s caffeine consumption should be closely monitored. Although caffeine is safe to consume in moderation, it may negatively affect a child’s nutrition. Caffeinated beverages may be replacing nutrient dense foods such as fruit juices and milk. A child may also eat less because caffeine acts as an appetite suppressant (Kids Walmar). Caffeine can be completely restricted in a child’s diet since there is no nutritional requirement for it. This may be necessary for a hyperactive child as caffeine is a central nervous stimulant (Caffeine Blues Cherniske). Caffeine can also affect pregnant women and other special cases. Pregnant women and people with coronary heart disease or peptic ulcers may be advised by their health care provider to restrict or avoid using caffeine (Chronic Temples).
Like anything, there are two sides to the story. However, with research, one side ways heavily over the other. The negative affects caffeine is associated with push aside the few good affects. From what was read so far, caffeine intake does more harm than good.
_Scientific Experiment
I. Purpose: The purpose of this experiment is to determine the affects of the compound caffeine (C8H10N4O2) on the human body relating to: a) If caffeine causes dependency; b) How caffeine affects our body?s nervous system; c) How caffeine affects our digestive system.
II. Materials:
? 100 human subjects (no caffeine in body)
? 1800 10mg caffeine pills (20 subjects for 90 days)
? 1800 40mg caffeine pills (20 subjects for 90 days)
? 1800 70mg caffeine pills (20 subjects for 90 days)
? 1800 100mg caffeine pills (20 subjects for 90 days)
? 1800 placebo pills (water filled) (20 subjects for 90 days)
? Same diet for all (100) subjects for 90 days
? Tools to measure heart rate (clocks) ? for all subjects
? Urine cups for all subjects once every week (every 7 days)
? Dependency questionnaire for all subjects once every week (every 7 days)
? Sufficient staff to carry out the procedure
III. Procedure:
1) Acquire 100 human subjects who do not have caffeine in their body (have not used caffeine for 1 week).
2) Randomly divide the 100 human subjects into 5 blocks (groups).
3) Randomly assign each block a treatment ?
Treatment#1 placebo
Treatment#2 10mg caffeine pill
Treatment#3 40mg caffeine pill
Treatment#4 70mg caffeine pill
Treatment#5 100mg caffeine pill
4) For each block, give the same diet every day for 90 days.
5) For each block set all reasonable variables the same (including exercise)
6) For each block, give 1 pill of randomly selected treatment to each subject every day for 90 days. Distribute the pill in a double blind fashion (subject and distributor doesn?t know which pill is being given ? to reduce bias).
7) On every 7th day (7th day, 14th day, 21st day, 28th day, etc.), give out dependency questionnaire (asks craving toward treatment on a 1-10 scale) to each subject. Take until the 90th day.
8) Record results according to each block.
9) Starting on the 8th day following by increments of 7 days (8th day, 15th day, 22nd day, 29th day, etc.), measure each subjects pulse rate. Measure pulses when subjects wake from sleeping at 7:00AM (resting pulse).Take until the 90th day.
10) Starting on the 9th day following by increments of 7 days (9th day, 16th day, 23rd day, 30th day, etc.), take urine samples from each subject to measure dehydration. Take until the 90th day.
11) Record results according to each block.
12) Gather results for each block and each of the three tests (15 sets of data).
Procedure for significance tests
13) For the dependency test carry out 4 ?2 sample z-tests?. Each block will be set against the control group. Here are the null and alternative hypotheses for all 4 of the tests:
U1=Mean of control?s dependency level
U2=Mean of block?s (all non-control block?s) dependency level
Ho: U1=U2 The control group?s mean dependency level equals the block?s mean dependency level.
Ha: U1*U2 The control group?s mean is less than the block?s mean dependency level. (Caffeine causes dependency)
14) For the pulse rate test carry out 4 ?2 sample z-tests?. Each block will be set against the control group. Here are the null and alternative hypotheses for all 4 of the tests:
U1=Mean of control?s pulse rate
U2=Mean of block?s (all non-control block?s) pulse rate
Ho: U1=U2 The control group?s mean pulse rate equals the block?s mean pulse rate.
Ha: U1*U2 The control group?s mean pulse rate is less than the block?s mean pulse rate. (Caffeine speeds up nervous system)
15) For the dehydration test carry out 4 ?2 sample z-tests?. Each block will be set against the control group. Here are the null and alternative hypotheses for all 4 of the tests:
U1=Mean of control?s volume of urine
U2=Mean of block?s (all non-control block?s) volume of urine
Ho: U1=U2 The control group?s mean volume of urine equals the block?s mean volume of urine.
Ha: U1*U2 The control group?s mean volume of urine is less than the block?s mean volume of urine. (Caffeine dehydrates the body)
16) For all tests set alpha to .05 (alpha = .05).
17) Draw conclusions from each significance tests (Probability is either below or above the alpha).
18) For each of the three main tests (dependency, pulse rate, and dehydration), compare and contrast all the significance tests for each block and make a master conclusion relating the significance tests to each other.
? The experiment is completed
___Statement of Hypothesis
Based on research of caffeine and other scientist?s previous experiments, caffeine will cause a slight dependency (my probability will be larger than my alpha) in human subjects. In Caffeine Consumed (Walton), it says that caffeine has been found addictive in many studies. Furthermore, based on reading from Robert Winston?s ?Withdrawal Caffeine? experiment, he believes that caffeine is the most widely consumed behaviorally active substance in the world, chronic caffeine intake only appears to have minor negative affects on health, and that is why government regulatory agencies do not impose restrictions on it. He has experimentally proved this. Numerous others have found caffeine guilty of producing withdrawal symptoms and other forms of dependency also.
Caffeine?s reason for being part of an early morning ritual for millions of people around the world is its ability to wake up one?s body. It has been scientifically proven many times that caffeine accomplishes this task by speeding up the nervous system (Anderson ?Decaff Anyone??). Therefore, caffeine will increase pulse rate (probability greater than alpha).
Although not many articles on the effects of caffeine on the digestive system were read, one article analyzed this subject very well. Powers Sk, ?Caffeine and Endurance performance? it asserts that caffeine is a major diuretic. The caffeine goes through one?s system offering little nutritional value, and exiting the system by dehydrating it. Hence, caffeine in large amounts will create dehydration on the digestive system (probability greater than alpha).
Because of extensive research and a well-thought experiment, I know a lot more about caffeine. Though it would have been easy to accept the ideas and theories of my father, thoroughly investigating this problem has supplied information that is more reliable. Undergoing the experiment will be the final step to my investigation on caffeine.
Bibliography
___Bibliography
1) Caffeine Blues, Stephen A. Cherniske, M.S. (Warner Books, 1998).
2) Caffeine Consumed, R. Jacobs Miller. (Coyote Canyon, 1981).
3) ?Chronic caffeine intake alters the composition of various parts of the brain in young growing rats?, Nakamoto, Temples TE. Dev Pharmacol Ther 1988
4) ?Caffeine and Endurance Performance?, Powers Sk. Sports Med 1985 May-Jun;23:165-74.
5) Encyclopedia Britannica, Caffeine, 1999.
6) ?Caffeine side affects and your kids?, Walmer K, Scientific America. 1992.
! |
Как писать рефераты Практические рекомендации по написанию студенческих рефератов. |
! | План реферата Краткий список разделов, отражающий структура и порядок работы над будующим рефератом. |
! | Введение реферата Вводная часть работы, в которой отражается цель и обозначается список задач. |
! | Заключение реферата В заключении подводятся итоги, описывается была ли достигнута поставленная цель, каковы результаты. |
! | Оформление рефератов Методические рекомендации по грамотному оформлению работы по ГОСТ. |
→ | Виды рефератов Какими бывают рефераты по своему назначению и структуре. |