Caffeine Induces Anxiety in College Students
Caffeine Induces Anxiety in College Students
What is Caffeine?
Caffeine also known as methyl xanthine, 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione, theine, theobrine, and 1,3,7-trimethylxanthine (Newton, 2014) is an alkaloid crystal white in color powder. It is bitter to the tongue and has powerful antioxidant traits (Alpert,2012). Being apart of the alkaloid family, caffeine is a chemical compound that is identified in many organisms. A part of caffeine’s chemical compound make-up is nitrogen and is in complex multi-ring form. (Thomasson, 2014). The complete chemical structure of caffeine is C8H10N4O2 H2O, these elements are Carbon, Hydrogen, Nitrogen, Oxygen, and the addition of the compound water. (Newton, 2014) Caffeine is also a methylxanthine, which is a phytochemical created from xanthine and is retrieved from plant supporting metabolism. (Monteiro, Alves, Oliveira, & Silva, 2016)
Caffeine is considered an organic stimulant, it arouses the central nervous system and intensifies cyclic adenosine monophosphate (AMP) activity. Caffeine can travel through several molecular passages in the body, which can cause several biological and physiological reactions. (Tolley, 2014). Caffeine is mostly ingested orally so it begins its process being absorbed through the small intestine and metabolized through the liver. Then, caffeine travels to all body tissue, passes through the blood brain barrier, blood-placenta barrier, and the blood-testis barrier, However, with everyone it differs how caffeine travels, breaks down, and exits the body, so the reactions differ. Because of these differences caffeine can have effects on the body from a minimum of 2 hours to a maximum of 12 hours.
One way caffeine can travel through the body and take effect is by obstructing adenosine receptors. (Cappelletti, Daria, Sani, & Aromatario, 2015). Adenosine receptors have a part in many bodily functions such as sleep, regulation of pain, circulation, immune function and cardiac rhythm (Welch, 2015). Because caffeine blocks adenosine receptors, a surge of hormones is released, including dopamine, norepinephrine, and serotonin (Monteiro et el, 2016). When adenosine receptors are blocked alertness, wakefulness, and focus are temporarily increased (Alpert,2012).
History and Forms of Caffeine Popularly Consumed
Caffeine can be found in over sixty plants around the world and it is theorized that caffeine acts as a protector to plants. Caffeine is not needed for any plant to survive, yet it is found in many plants. The traces of caffeine found in plants is toxic to many insects and animals, primarily herbivores (Cappelletti et al., 2015). Of the sixty plus plants that caffeine is found in, the most popular species known are Paullinia, Coffea, Theobroma, Ilex, and Camellia (Russo, & Romano, 2012). Humans began to realize the benefits of caffeine in the stone age era. Humans would chew or consume certain bark, berries, or plants that contained caffeine. These certain plants would reduce tiredness and increase alertness to those who consumed it. Soaking leaves containing caffeine in hot water was discovered in the 10th century B.C.E in China. Making other beverages with caffeine like spicy hot chocolate was discovered in the 10th century B.C.E by the Olmec people in the Gulf of Mexico. In the 3rd century C.E in Ethiopia people would collect coffee beans from ashes and crush them in water. Again, in Ethiopia wrapping beans containing caffeine in lard was discovered in the 9th century C.E. Extracting caffeine by decaffeination was discovered in the 20th century and started the use of caffeine in many other beverages and in the medical field (Alpert, 2012).
Caffeine can also be created synthetically by placing malonic acid and dimethyl carbamide together, or theobromine being methylated. Synthetic caffeine especially in pure form can be dangerous. (Russo, & Romano, 2012). Presently, the most popular consumed items with caffeine are coffee, tea, chocolate, soft drinks, and energy drinks. These popular items all come from those popular plants mentioned earlier.
Coffee. After water, coffee is the greatest utilized beverage in the world. Caffeine content in coffee varies depending upon which plant the coffee bean comes from, how it is processed, and how it is brewed. Robusta bean plants have 2% or more caffeine concentration, while Arabica bean plants only have 1% concentration of caffeine (Massey, 2016). Coffee beans come from a tree that buds flowers, which holds a fruit, that contains the coffee bean. The flower that contain the fruit are usually white, however the fruit can vary in color such as yellow, red, orange, and pink. After the fruit is retrieved, three layers of the fruit must be removed to get the bean. (Steiman, Morris, & Thurston 2013). Although the fruit contain other layers, none of the layers contain caffeine, resulting in large amounts of waste (Massey, 2016). The bean is then dried out to finally begin processing (Steiman, Morris, & Thurston 2013).
The roasting process extracts more caffeine but, in a less concentrated form. The expresso process extracts less caffeine but in higher concentration, so it is more potent. A Turkish way of brewing involves mixing ground coffee and hot water together but, leaving the residual ground coffee as a part of the final serving. Since the ground coffee is mixed with water for a longer period it does dilute the caffeine concentration however, because the coffee residue remains it adds some concentration back.
Another example of brewing would be with an automatic coffee machine.
In the automatic method water is slowly dispensed through a filter holding coffee grounds and collected underneath the filter. This process is fast and does not allow the water to contact the coffee grounds for long, so the caffeine content by automatic machine is very diluted (Goodman, 2012).
Tea. After water and coffee, tea is the third most consumed beverage worldwide. However, it is the second cheapest beverage to purchase after water. All tea leaves come from the plant Camellia sinensis (Tolley, 2014). Caffeine released in tea depends on the size of the leaf and fermentation. Smaller leaves, like ones found in tea bags release more caffeine than whole tea leaves. The entire Camellia plant contains caffeine but, only the leaves are used for creation of tea. Tea has a higher concentration of caffeine than coffee, however, since it is served in large quantities of water the caffeine becomes diluted (Khan, & Mukhtar, 2013).
There are three popular fermentation processes to create black, oolong, and green tea leaves. Black tea leaves are created by first fermenting them by oxidizing them in air for many hours, then smoked or steamed. Oolong tea leaves are created by a half fermentation process it is similar to how black tea is made but, the process is shorter. Green tea is not fermented at all. The leaves are picked at an earlier stage and prevented from being able to oxidize, they go directly into the steaming, smoking, or panning process. Black tea has the highest caffeine content, next is oolong, and last is green. (Khan, & Mukhtar, 2013).
Energy drinks/ soft drinks. Most energy drinks and soft drinks are made with synthetic caffeine and a plant called Guarana that also has caffeine in it (Woolf, & Brown, 2008).
Guarana is a vine plant with berry shaped fruit containing seeds originating in South America.
According to history it was first discovered in Brazil and then reached other parts of South America. The Guarana seeds have the highest caffeine concentration, beating out coffee, tea, and the other sixty plants with concentrations ranging from 2% to 7.5%. The process of obtaining Guarana seeds is more complex than coffee. The first layer of the fruit is opened exposing the seed when it is ripe, the skin surrounding the seed must soften for a few days, be peeled by hand, roasted on a large griddle, crushed by a mortar, mixed with water, shaped into cylinders, dried in the sun, and then smoked for a few weeks. Guarana can also be left in the powder form from being crushed by the mortar, but it loses its flavor and potency faster than the cylinder form. (Smith, & Atroch, 2010).
The FDA has regulations on how much caffeine is allowed in soda which is 65 mg caffeine per 12oz. Energy drinks are not considered soda or soft drinks and do not have to follow those guide lines. (Rath, 2012). Guarana is considered a natural ingredient and the caffeine content from this plant that is incorporated into drinks is not required nor often reported to consumers (Woolf, & Brown, 2008). For example, (Zhang, et el, 2012) conducted a study on the caffeine content of 38 different beverages including soft drinks and energy drinks. The results found that out of the 38 beverages, four had mislabeled caffeine content listed (Zhang, et el, 2012).
Synthetic caffeine is created in laboratories and mass-produced in factories only. As mentioned earlier, there are several ways to create synthetic caffeine such as methylation of theobromine and combining carbamide and malonic acid together (Russo, Romano, 2012). There are a few other ways to create synthetic caffeine such as by using raw urea and synthesizing it, or exposing urea to strong chemicals like ethyl acetate, carbon dioxide and methylated chloride. Synthetic caffeine is stronger than any plant-based caffeine including Guarana.
Because synthetic caffeine is much stronger than plant-based caffeine it passes through the small intestine and metabolizes faster than plant-based caffeine. The synthetic caffeine being quickly metabolized, creates quicker increases in energy, but also a faster caffeine crash. Synthetic caffeine does not hold any vitamins or nutritional value like plant-based caffeine does, so consuming it makes one more likely to experience adverse effects (Ettinger, 2011). Unlike coffee, tea, and soda, energy drink consumption became prominent when Red Bull was released in 1997 (Malinauskas, Aeby, Overton, Carpenter-Aeby, Barbara-Heidal 2012).
College Students and Consumption of Caffeine
In the last decade, companies with caffeine containing products have increased their advertisement efforts toward young adults and adolescents and there has been a large increase of caffeine consumption in these populations. (Paulus, et el, 2015) In the U.S in 2007 amongst the population of 18-24-year-old persons, 37% reported consuming coffee according to the National Coffee Association (McIlvain, Noland, & Bickel, 2011). 400 mg of caffeine per day is the recommended peak of caffeine for an adult in good health (Zhang, et el, 2012). However, the National Library of Medicine sanctions a lower daily dose of caffeine at 200-300 mg for a healthy adult (Paulus, et el, 2015).
Some examples of caffeine content in popular coffee beverages are: Starbucks Grande 16oz coffee 372 mg, Starbucks Tall 120z Caffe Latte 58 mg, Starbucks Grande 16oz Latte Macchiato 225mg, Dunkin Donuts 24oz Iced Coffee 297 mg, Dunkin Donuts 14oz Brewed Coffee 210 mg, Peet’s 16oz Brewed Coffee 267, Peet’s 16oz Caffe Latte 140 mg, Folgers Coffee 8oz 112mg, and McDonald’s 22oz Iced Coffee 200mg. Caffeine content in popular tea beverages include 8oz Black tea 42 mg, 80z Green tea 25mg, 80z Oolong 37mg, Turkey Hill 16.2 oz Iced tea 110 mg, Teavana 8oz Tea 41 mg, and Chai 8oz Tea 50 mg. Caffeine content of popular energy drinks include Red Bull 8.4oz 80mg, Monster Energy Drink 16 oz 160mg, Amp Energy
Drink 16oz 142mg, Rockstar Energy Drink 16 oz 160 mg, and NOS Energy Drink 16 oz 160 mg. Popular soda caffeine content include Coca-Cola 12 oz 34 mg, Pepsi Cola 12 oz 38mg, Sprite 12 oz 0 mg, Diet Coke 12 oz 46 mg, and 12 oz Dr. Pepper 41 mg. (Caffeine Informer, n.d.).
All beverages above meet the criteria of being below the recommended intake of 200-400mg per day. However, college students usually consume more than one of these beverages or a combination of these beverages. In a study done by McIlvain, Noland, & Bickel, 2011 300 freshman college students from Marshall University in West Virginia were evaluated for caffeine consumption, thoughts, and experiences with caffeine. Caffeine consumption in this study was calculated by the creation of an expansive list of caffeinated beverages and serving size. Students were asked which and how much of each drink they consumed in a day. The results showed that the average intake of caffeine amongst the students was 849.86 mg per day. (McIlvain, Noland, & Bickel, 2011). Another study done by K??§er, 2010 in Turkey at the Kocaeli Vocational School of Health Services surveyed 156 students to discover the student’s daily caffeine intake and their experience with caffeine. A list of Turkish caffeinated items was distributed to students to report items they had consumed daily. The study results showed the average daily intake of students ranged from 0 mg to 500 mg with 51 percent of student’s intakes ranging from 0 mg to 200 mg and 49 percent of students ranging from 200 mg to 400+ mg (Kuler, 2010).
Another study, done in Pakistan at Dow University of Health Science by Khan, Nisar, Naqvi & Nawab, 2017 was a cross-sectional study was done with 400 medical students over the course of 5 months. Although this study did not collect exact caffeine intake, it did cover how many students use caffeine and their beliefs. The results showed that only 6% (24 students), did not use caffeine in any form (Khan, Nisar, Naqvi & Nawab, 2017). Another cross-sectional study done in Dubai at Zayed university by M. Al Ghali, Al Shaibi, Al Majed, & Haroun, 2017 studied 175 student’s caffeine intakes through self-report. 86% of students consumed caffeine. The average daily caffeine intake in this study was 249.7 ?± 235.9 mg (M. Al Ghali, et el, 2017) Another study done by Malinauskas, Aeby, Overton, Carpenter-Aeby, Barbara-Heidal 2012 surveyed 496 students from different universities over the Central Atlantic region of the U.S. The study assessed energy drink consumption intake on a given month and reasoning for using energy drinks. The study showed that 253 students 51% reported consuming at least one energy drink per month (Malinauskas, Aeby, Overton, Carpenter-Aeby, Barbara-Heidal, 2012). The last study was done in Benin, Africa to get a report on how many students were just consuming caffeine period. This study was done at the University of Benin with 485 participants. Of the 485 students, 39.6 (192 students) percent were using caffeine at the time of the study. Although it is less than 50% of student it is still a significant number of students using caffeine (Adayonfo, Akanni, & Ehimigbai. 2016). These studies show that caffeine is highly favored and used in one way or another by many college students.
Defining anxiety began in the 5th and 4th centuries B.C.E when professionals began discussing sanity, insanity and forms of fear. Amongst the Greek civilization and later the Roman civilization, social status and esteem was more important than emotions. Anxiety to Greek civilization was the expectation that forms of trouble such as sickness, war, loneliness, poverty, and mortality would come. Although, anxiety was understood to be felt by every human, it was considered a bad characteristic if men could not successfully hide it, especially in times of war. It was an extreme disgrace if fear or anxiety could be detected from one man to another.
In mid-4th century the idea of fears and anxiety shifted to the focus of humors. There were 4 humors responsible for the functioning and wellbeing of humans, including blood, phlegm, black bile, and yellow bile. Anxiety was thought to be because of an excess of black bile. From the late 4th century to the 1st century it was believed that separating oneself from fear and unachievable desires would relieve anxiety and create a joyful life (Horwitz, 2013). In the middle ages from the 5th to 17th centuries anxiety was merged into the same category as
melancholy and depression. In these centuries in Chinese medicine, anxiety was considered an issue stemming from the kidneys.
In the beginning of the 18th century anxiety took a back track and went back to being considered a natural part of human life. Anxiety was still being lumped together with other feelings and states of being such as worry, fear, anger, panic, and depression. In the late 18th century, professionals finally started to study and recognize a difference between regular worries and constant anxiety. However, anxiety was still just considered a mild mental problem made by abnormalities in the mind. Professionals were still focused on conditions that were considered major at the time that required therapy and hospitalization.
In the 19th century, Freud stemming from the idea of Hecker, introduced the idea to separate anxiety from being mixed in as a symptom in other disorders. He proposed that anxiety be put into its own category called anxiety neurosis. Anxiety neurosis had 4 categories of disorders under it. The disorders were known as avoidance of phobias, general irritability, consistent apprehension, and anxiety spasms. Soon after Freud introduced anxiety categories of free-floating, generalized, and persistent.
In the 20th century, the terminology of generalized anxiety appears in the DSM-III.
Before this, anxiety appeared in previous additions as a part of psych neuroticism. (Guglielmo, Janiri, & Pozzi, 2014). However, because of the war, a nonmedical view of anxiety gained great attention and clout. This non-medical view claimed that anxiety was a normal response to societal situations and required government action. In the non-medical view, like in the 18th century anxiety was associated with everyday stressors such as overworking, marriage, raising children, and worldwide stressors such as war, tension between countries, and economy. Because many people diagnosed themselves with anxiety during the 20th century, there was a large outcry for remedies and treatments. Psychoanalysis was a small practice at the time, so people turned to their primary care physicians for relief (Horwitz, 2013).
In the 21st century much like the 5th and 4th century Greek definition, the DSM-5 defines anxiety as the “anticipation of future threat” and fear is “the emotional response to real or perceived imminent threat.” Anxiety has its own category in the DSM-5 with disorders in a spectrum all related to anxiety. These disorders include panic, phobia, agoraphobia, separation, social, post traumatic stress, and generalized (American Psychiatric, p.1-7, 2016). Scientist are now looking at the mental and physical aspects of anxiety. Scientific investigation of the brain now includes trying to figure out where in the brain does anxiety stem from and why it may cause physical symptoms. Neuroscientist have gathered that the brain regions involved with anxiety include pre-frontal cortex, amygdala, and hippocampus. With these new findings, scientist can now create remedies and medications specific to neurotransmitters and brain functioning related to anxiety (Horwitz, 2013). Although in the 21st century anxiety is now a vast field of study, for this study the concentration will be on Generalized Anxiety Disorder and its symptoms in relationship with college students and their caffeine intake.
Generalized Anxiety Disorder
To an extent, the 18th and 20th centuries were correct, feeling worry and anxiety is natural. One may feel worry or anxiety about a life changing event such as moving, new job, unexpected bill, and unexpected illness. College students may worry about, assignments due, working part time, and family issues. Small amounts of worry and anxiety can be used as an encourager to stay motivated and finish tasks (Healey, 2014). However, Generalized Anxiety Disorder (GAD) is recognized when the feelings of worry and fear are overwhelming with no explanation or obvious cause.
Persons suffering with GAD find it impossible to complete daily task, focus, or to stop worrying once started because of the overwhelming fear and worry. Other symptoms of GAD include excessive bathroom use, profuse sweating, breathlessness, light headedness, irritability, racing heart, trouble focusing, startles easily, fidgeting, body pains, and shaking. It is unknown how GAD is developed however, it can worsen in stressful situations (“NIMH ?» Generalized Anxiety Disorder: When Worry Gets Out of Control,” 2016).
One of the first signs a person with GAD may notice is body pain or other changes in the body. The stomach may become upset, tension may develop in the neck and shoulders, and feelings of fatigue but unable to rest properly. People will visit their primary care doctors and want to get treated for body pain but may not think to include the symptom of constant worry or fear.
Some personality traits that may come with GAD include being unable to cope with the unknown, extreme effort at perfection, continuous checking on people or tasks, trouble making small decisions, excessive researching, excessive task creation, unwilling to let others complete tasks, prolonging tasks, excluding oneself from new relationships, excluding oneself from new opportunities, distracting oneself from other tasks, and bestowing the responsibility of making decisions onto other people. Having GAD can be extremely debilitating to a person, one worry builds from another worry creating a snowball effect of worrying that seems to never end. For example, a college student may have several assignments due at the same time, one may start to worry if assignments can be turned in on time, if one can achieve passing grades, then worry if one will graduate, then worry if one could find a good job or how much longer one would be in school, to how a marriage or relationship would work out if one did not have a degree, etc.
The worry and fear would be so hard to contain that the student may not get any work done. These symptoms must be manifested for half of a year to be considered GAD (Anxiety Disorders Association of British Columbia, 2017).
College Students, Caffeine, and Anxiety
The college experience is a unique one for all who partake in it. If one is living on campus or living away from parental influences, everyday life decisions fall onto that person and independence is experienced. College students have the freedom to dictate every aspect of their lives including eating, drinking, class scheduling, activities, sleeping, completion of assignments, and leisure time (Scheiwe, 2003). The freedom, demands, and scheduling during college years can become stressful or worrisome. Some colleges usually offer, academic advisors, success advisors, and counselors to help students succeed and cope with college life. Amongst colleges these resources are not advertised well enough to students and students who are aware of them may view seeking these extra resources as a nuisance or unhelpful (Bhujade, 2017). However, in a study done by Wig, et el 1969, 68 students were placed in counseling, 50% of the students reported finding difficulty in concentrating, 24% reported feelings of sadness, 23.5% reported head pain, and 23.5% reported feeling nervous (as cited in Bhujade, 2017).
The caffeine intake of these students in this study is unknown. However, in modern times with early morning classes, late night papers, and other daily demands caffeine consumption is an everyday ritual for many college students because of the advertised outcomes caffeine can have on a person. Self- helps like caffeine consumption, smoking, over indulgence in food, exercise, intimate relationships and drinking are more common amongst college students because it takes less time and effort than seeking out other forms of help. Students may also use self-help methods instead of academics out of embarrassment of being unable to cope with college life (Scheiwe, 2003).
College Student Beliefs and Experiences with Caffeine
The beliefs about caffeine and experiences with caffeine amongst college students can vary depending on where they are from, what university they go to, what religious beliefs they hold, and how caffeine consumption has affected them in the past. For example, according to BBC News in September 2017, Mormon college Brigham Young University has just lifted its almost 70-year ban on caffeine. The university now sells soda with caffeine in it, but still does not allow highly caffeinated drinks such as energy drinks This means that due to religious views and the university they attended, the students at this university were excluded from caffeine usage. The students had been challenging the university’s decision since 2012. They wanted the right to choose to consume caffeine since it did not interfere with the university’s and Mormon religion standard of abstaining from alcohol and maintaining purity (BBC News, 2017). At Marshall University, a study was done on 300 freshmen class students to explore their beliefs about caffeine. In this study 79.7% (239 students) believed caffeine was harmful to them, 43% (129 students) believed caffeine disturbs coordination, and 82.3% (247 students) believed caffeine is addictive. However, contrary to those beliefs this study showed that 65% (195 students) drank caffeine daily, 76% (229 students) believed caffeine increased wakefulness, and 76.3 (229 students) used caffeine to stay awake (McIlvain, Noland, & Bickel, 2011). In a study done by Parker-Pope 2008, one third of 12-24-year-old persons reported using energy drinks because they were fond of the taste, wanted to stay awake for night study sessions, or wanted to increase overall wakefulness throughout the day (as cited by Liberatore, 2009).
Another study done focused on energy drink consumption and reasons was done in the Central Atlantic part of the U.S to 496 students. In this study, 67 % of students used energy drinks due to lack of sleep, 65% wanted to increase energy, 50% used caffeine in preparation for studying or completing large assignments, and 54% used while drinking alcohol. Also, in this study, 29% felt an increase in energy and then an extreme plummet, 19% reported feeling heart palpitations, and 22% reported experiencing headaches (Malinauskas, Aeby, Overton, Carpenter-Aeby, Barbara-Heidal, 2012). Another study done at a university in Pakistan measured caffeine intake and academic performance. This study contained 384 students and 71.5% believed caffeine increases academic performance, 71% believed caffeine increased self-efficacy, 70% reported it increased wakefulness, and 22% believed caffeine increased IQ. Contrary to the student’s beliefs, 53.8 of the students gained a GPA above a 3.0 while the remaining gained below a 3.0 GPA. This result was average and showed that the correlation between increased GPA and caffeine consumption was low (Khan, Nisar, Naqvi & Nawab, 2017). In a study done in turkey at university 156 students were survey for caffeine intake and withdrawal symptoms such as headache, anxiety, inability to concentrate, etc. In the study student’s intake over 200 mg of caffeine daily reports included 20.7% headaches, 27.2% fatigue, 18.1% irritability, 32.4% drowsiness, 16.8 anxiety, 14.2 unable to concentrate, and 28.5 % reported no symptoms (K??§er, 2010). In this study, I hypothesize that caffeine consumption increases generalized anxiety symptoms in college students compared to those who do not consume caffeine.
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