It would be fair to say that caffeine is the most commonly used stimulant in today’s world and is consumed in a variety of forms. Historically, most cultures developed a form of caffeine that was linked to the plants found in the geographic area where that culture was located.
However, as humanity engaged in trading and communication with other cultures, caffeine spread across the world in a multitude of forms. In the past, tea and coffee were the predominant forms, but in the modern world, soda and energy drinks have become more and more common caffeine delivery systems. As wide spread as caffeine use has become, many people only have a limited understanding of this substance, the differences between the various delivery methods, and how these different forms affect the body. This purpose of this guide is to illustrate what caffeine is, compare and contrast some of the ways people ingest it, and point out some of the ways that it affects the body.
Caffeine occurs in nature as an oil that is exuded by plants as a toxin to keep insects at bay. This oil is exuded through the leaves and fruit of the various plants that are the source of coffee beans, tea leaves, and guarana fruit (among others). It acts as a neurotoxin on insects, leading to paralysis and coordination difficulties. This affect can also be seen in humans, though only at much higher doses. The basic equation for determining a toxic dose of caffeine in mammals is around 150-200 milligrams per kilogram of body mass (or around 80-100 cups of coffee for the average adult). This effect can be seen at lower doses as the loss of coordination, shakiness, increased heart rate, and higher blood pressure that comes with drinking too much caffeine in too short a time period. Coffee is an exception to this, as there are other elements in play which will be discussed later. The chances of an overdose are extremely rare however, as the body would filter most of the caffeine out of the body before a toxic dosage could be ingested. Also, in its pure form, caffeine powder is extremely bitter, making it almost impossible for any creature to consume a toxic dose orally.
Like most stimulants, caffeine affects the body by increasing neurological and metabolic rates, leading to increased blood flow and heart rate, which produces a feeling of wakefulness. In people who are not regular caffeine consumers, there is also a mild diuretic effect. However, caffeine tolerance builds fairly quickly and can turn into dependence in a relatively short time. The signs of caffeine withdrawal can include feelings of depression or anxiety, sleepiness, headaches, and nausea. Fortunately, this period of withdrawal is relatively short and for many people, the psychological addiction to caffeine is far harder to kick. In some cases, it has to do with the establishment of habits, such as the first cup of coffee to start the day, while for others it comes from a dislike of being aware of the natural cycles of energy and fatigue that occur throughout the day, such as sleepiness after meals.
Coffee is one of the oldest forms of caffeine that has been consumed by humans, second only to tea in the Western and Eastern world. The oils of the coffee bean are rich in caffeine as well as other substances that increase wakefulness and energy. One of the primary complaints about coffee is its bitter flavor which comes from the high levels of caffeine in the oil (this bitterness also contributes to the nausea that can arise from too much coffee consumption). The bitter nature of coffee does have some benefits in breaking down fats and proteins, which makes it a popular beverage to accompany the consumption of meals and desserts, especially heavy meals that may not digest comfortably without it. This makes it a popular choice as a breakfast or post-desert companion. The heavy foods also add the benefit of easing the effects of coffee’s acidity on the digestion, leading to less stomach upset and irritation.
As mentioned before, coffee has some characteristics that set it apart from other forms of caffeine. For one thing, oils separate from caffeine can stimulate the body to produce adrenaline and cortisol, two natural occurring hormones which have a major impact on wakefulness, energy, and body function. Adrenaline is a fairly well known substance and can be pointed to as one of the reason why coffee consumption tends to lead to increased levels of both physical and mental irritability as well as confrontation and aggression.
Cortisol, another naturally occurring steroid in the body, plays a much more subtle and less well known role. One of the primary functions of cortisol is control overall wakefulness and energy levels. To contrast it to adrenaline, which provides quick bursts of energy, strength, focus, and endurance, cortisol levels fluctuate throughout the day. As morning approaches, cortisol levels rise to make waking easier and allow the person to have the energy to start the day. They then level off and start to decrease, lowering energy levels and allowing sleep to come more easily. Cortisol also plays a large role in metabolism, helping to control blood sugar levels and lowering inflammation. This is one reason it is called the stress hormone, as a person whose body poorly manages its cortisol levels will be much more vulnerable to stress-based health issues. In people whose cortisol levels are too high or too low, sugar cravings, inflammatory conditions, swelling, respiration, and circulatory issues can all arise. A cup of coffee can be used to stop an asthma attack or reduce allergy symptoms, but high levels of cortisol can also lead to facial swelling and circulatory issues, among other problems.
The substances in the coffee bean oils that cause the body to increase the production of both adrenaline and cortisol are separate from the caffeine and can exist even in decaffeinated coffee. Their presence increases the effect coffee has in terms of providing a sense of wakefulness and energy, but also increase the amount of shakiness and irritability that are signs of caffeine over-consumption. They also decrease the amount of time it takes for caffeine dependence to set in as well as worsening the symptoms of withdrawal. Coffee is also very dehydrating, which can make both the symptoms of excessive consumption and withdrawal more intense.
Coffee, which is usually made by exposing the ground form of the roasted bean to boiling water, can also be prepared in a cold-pressed form. Using cold water often makes the process of extracting the coffee itself take a longer period of time, but it also makes the coffee sweeter in flavor as less of the other oils are released. This lack of bitterness also generally makes it easier to digest the coffee as the stomach is less irritated by it.
Tea, in comparison, has much higher levels of caffeine than coffee by weight, but is usually served in much smaller amounts in order to make it more palatable. The bitter nature of tea, defined here as the leaves from the plants of the Camellia Sinesis plant, has similar effects to coffee in terms of aiding with digestion or in causing stomach upset, but without the accompanying adrenaline or cortisol reactions. There is also an additional astringent effect due to an increased levels of tannins in the tea, which can also aid digestion. Generally, tea is thought to be a much gentler form of caffeine than coffee, and is consumed in much greater amounts with less negative side effects. However, high levels of caffeine can still have an overall negative impact on resting ability, even without the cortisol-altering elements found in coffee.
Tea leaves are generally sold in three different forms – black, green, and white. Black teas have been roasted to maximize the amount of caffeine available and are generally easier on the body, producing a warming effect. Green teas are only mildly prepared and have less caffeine available and contain a higher level of antioxidants, but they also have a cooling effect on the body, which can make them less appropriate for consumption in colder months or climates. White teas come from baby tea leaves and have the lowest levels of available caffeine but also the least effect on the body. All have a stronger diuretic effect on the body than coffee, partially because the lower amount of actual material used leads to a less dehydrating effect on the body.
Two other plants that are common sources of caffeine and which have become more widespread in their use in recent years are guarana and yerba matte. Guarana has twice the caffeine content of coffee and in comparison is more bitter in flavor, increases metabolism to a higher degree, and has more blood thinning effects. The greater bitterness has made it less popular as a standalone beverage, but it has become more popular lately as an ingredient in energy drinks and weight loss supplements (the majority of which are stimulants).
Yerba matte leaves have also become more popular lately as a source of caffeine, but due to some differences in how it effects the body, it is used less for stimulant purposes than coffee, tea, or guarana. It has more of an effect on the muscle tissues in the body than the central nervous system, giving those who consume it less of a feeling of wakefulness than the other common sources of caffeine. Instead of stimulating the nerves, it relaxes smooth muscle tissue and stimulates the myocardial tissue of the heart. This creates a more relaxed feeling overall, with less of the increased alertness that comes with other forms of caffeine, an alertness that is often the reason that caffeine is consumed in the first place.
Before moving on, it should also be noted that chocolate naturally contains some caffeine as well, but in much smaller doses. A 28 gram chocolate bar contains the same amount of caffeine as a cup of decaffeinated coffee, which can still be enough to have an effect on someone who has a low tolerance to it, but which is not enough on its own to create a caffeine “buzz”.
Sodas and energy drinks have, in recent years, become more and more popular in recent years as the caffeine delivery method of choice. However, because the ingredients used in making them contain no naturally occurring caffeine, the caffeine is instead added artificially. This caffeine is usually derived by boiling coffee or guarana beans or tea leaves and then collecting the caffeine from the water, or by steaming the beans or leaves and then spraying them with a solvent. It’s important to note that not all of these solvents can be removed, leading to some contamination of processed caffeines that their more naturally derived alternatives don’t have. This caffeine is then harvested as a bitter white powder and sold in bulk to various soda and energy drink manufacturers to be added in to these beverages as part of their production process. The concentrated form of caffeine is often incredibly bitter, which is why the manufacturers of these beverages often have to use so much sweetener. It’s necessary for them to cover the taste and often leads to the beverages incredible sweetness.
Because they use a more concentrated form of caffeine while also covering up the bitterness with a greater amount of sweeteners and fluid, these drinks are often consumed in much high quantities than either coffee or tea. Unfortunately, that means that a much higher amount of calories are also consumed. Some manufacturers will attempt to counter this by using artificial sweeteners, but many of those will also negatively affect the metabolism as well. This is one reason that the consumption of soda and energy drinks has been repeatedly linked to the obesity epidemic currently affecting the developed nations of the world.
Another risk with artificially caffeinated beverages, much more commonly seen in energy drinks than soda, is that they often have other herbs, minerals, and vitamins added to them in order to maximize their effects in raising the energy level of the individual consuming them. Ginseng, taurine, and vitamin B12 are all examples of commonly added supplements which can increase energy but which have their own risks. Ginseng is an herb which has a strong effect as a stimulant and is often used to treat congenital deficiency in Chinese herbal medicine. Used improperly, however, it can have negative affects on the metabolism and cardiovascular system and create increased anxiety. Taurine is an amino acid that can also boost energy, but in increased amounts can also lead to increased heart rate which can contribute to feelings of anxiety and raise the metabolism past comfortable levels. Vitamin B12 is often used to treat both anxiety and depression as well as certain forms of anemia and neurological disorders, but can have similar negative effects when used in a high dosage.
Another disadvantage to sodas and energy drinks is because they are consumed cold and usually in much greater amounts than coffee and tea, they often hide the effects of dehydration more than latter. This can contribute to the crash effect that occurs as these substances wear off, which often prompts the consumption of more beverages. Adding to this effect are the greater levels of sugar they contain (which can increase dehydration and stimulate urination). Combined, this cycle of higher consumption and urination often robs the body of needed electrolytes which then further increases the lack of energy and feelings of fatigue.
A final note on energy drinks is that they are sometimes combined with alcoholic beverages, either pre- or post-production (in other words, either on the shelves as an alcoholic beverage or mixed with alcohol at the bar). A large part of this is to combat alcohol’s depressive effects and allow people to feel aware and awake later into the night. Not surprisingly, this is very common in dance clubs. Unfortunately, the stimulating effects of the energy drinks often hide the effects of the alcohol, leading to an increased chance of alcohol over-consumption that leads to negative events due to the individual being unaware of how inebriated they are.
So, as a final comparison, each form of caffeine has its own benefits and costs, and for many people, these benefits and costs may mean far less to them than personal taste preferences, convenience, and habit. But for those who wish to lessen the impact of their favorite form of liquid energy, hopefully this guide will at least give them a starting point to either alter which form they consume or alter other habits to remove some of the more harmful side effects they may encounter. As always, hopefully this information will be of use and in the meantime, stay safe and stay healthy.