Caffeine is an addictive, legal, central nervous system stimulant (Fisone, Borgkvist & Usiello, 2004). Classified by the US Food and Drug Administration as "generally recognized as safe", caffeine is the world's most widely consumed psychoactive drug, and a major worldwide source is coffee. Roughly 90% of the adult population consider themselves to consume about two cups of coffee each day. Caffeine can be helpful or harmful, depending on how it is used. One would have to consume upwards of fifty cups of coffee in one day to die from this substance. However, even small quantities of caffeine cause nervousness and can lead to a roller-coaster of highs and lows. Caffeine, being both water and fat soluble, is quickly distributed in the body after absorption mainly by the small intestine, resulting in peaking plasma levels after 15-120 minutes, and a half-life of about 5–6 hours. Due to its fat-soluble properties, caffeine crosses the blood-brain barrier, and is metabolized in the liver (Pesta, Angadi, Burtscher & Roberts, 2013).
Caffeine directly affects both the central nervous system and skeletal muscle. It also has diuretic properties, increasing the removal of water from the body. This effect may potentially improve exercise performance during prolonged endurance events. Albeit, consuming four to seven cups of coffee per day can cause restlessness, tremors and tachycardia. In addition, researchers have observed that caffeine consumption leads to symptoms of overlap with those of many psychiatric disorders, including, but not limited to, anxiety, sleep disorders, exacerbation of eating disorders, hostility, and other psychotic symptoms (Winston, Hardwick & Jaberi, 2005). Caffeine stimulates the central nervous system by deceiving the brain into ordering the release of excess adrenaline, thus mimicking a response of the sympathetic nervous system. Therefore, caffeine quite literally puts your body into a state of fight or flight. Additionally, this excess adrenaline builds up in the muscles of body, causing body tension, headaches, and muscle spasms. Furthermore, since the adrenal glands are being artificially stimulated, they may not have ample time to rest and repair, resulting is depleted and weak performance. This in turn, results in increased feelings of exhaustion, even when the brain orders the release of adrenaline (whether stimulated by caffeine or naturally). Ultimately, by consuming caffeine, you may find that you become accustomed to caffeine, requiring need more and more caffeine to feel awake or even normal.
Caffeine directly affects both the central nervous system and skeletal muscle. It also has diuretic properties, increasing the removal of water from the body. This effect may potentially improve exercise performance during prolonged endurance events. Albeit, consuming four to seven cups of coffee per day can cause restlessness, tremors and tachycardia. In addition, researchers have observed that caffeine consumption leads to symptoms of overlap with those of many psychiatric disorders, including, but not limited to, anxiety, sleep disorders, exacerbation of eating disorders, hostility, and other psychotic symptoms (Winston, Hardwick & Jaberi, 2005). Caffeine stimulates the central nervous system by deceiving the brain into ordering the release of excess adrenaline, thus mimicking a response of the sympathetic nervous system. Therefore, caffeine quite literally puts your body into a state of fight or flight. Additionally, this excess adrenaline builds up in the muscles of body, causing body tension, headaches, and muscle spasms. Furthermore, since the adrenal glands are being artificially stimulated, they may not have ample time to rest and repair, resulting is depleted and weak performance. This in turn, results in increased feelings of exhaustion, even when the brain orders the release of adrenaline (whether stimulated by caffeine or naturally). Ultimately, by consuming caffeine, you may find that you become accustomed to caffeine, requiring need more and more caffeine to feel awake or even normal.
Mechanism of Action
Caffeine exerts its psychoactive effects on the human body mainly by five mechanisms:
- Adenosine antagonist. Due to its close chemical resemblance of adenosine, caffeine blocks adenosine receptors, thereby competitively inhibiting its action. Caffeine can decrease cerebral blood flow as well as antagonize specific adenosine receptors in blood vessels, resulting in decreased blood flow to the heart.
- Increases fatty acid oxidation. Increased fat breakdown leads to decreased reliance on glycogen use. Caffeine alters the energy system in which the body derives fuel from glycogen to fat mainly by increasing hormone sensitive lipase (HSL) activity.
- Inhibits phosphodiesterase enzymes. Phosphodiesterases inhibit the breakdown of cAMP, a presursor of ATP, the energy currency. It further activates a number of enzymes involved in glucose and lipid metabolism.
- Increases post-exercise muscle glycogen accumulation. Theoretically, increasing the rate of glycogen resynthesis results in enhanced recovery. Albeit, more research needs to be conducted.
- Mobilizes intracellular calcium. Researchers have observed that caffeine can enhance calcium release from the sarcoplasmic reticulum and can also inhibit its reuptake. Consequently, caffeine may enhance contractile force during submaximal muscular contractions in caffeine consumers. More research needs to be conducted.
Influence on Performance
Caffeine reduces fatigue and increases alertness, and athletes regularly use it as a potential ergogenic aid. Caffeine-induced increases in performance have been observed in aerobic and anaerobic sports. For caffeine to have an ergogenic effect, the dose should be approximately 5–6 mg/kg an hour before exercise. Higher doses, above 6 mg/kg, do not necessarily improve performance. More research needs to be conducted, as some studies found enhanced performance after coffee consumption, others did not.
Caffeine also produces a small but significant analgesic effect, potentially mediated by augmenting plasma endorphin concentrations. It is also established that caffeine reduces the rate of perceived exertion during exercise, suggesting that athletes are able to sustain higher intensities but do not perceive this effort to be different from placebo conditions.
Caffeine also produces a small but significant analgesic effect, potentially mediated by augmenting plasma endorphin concentrations. It is also established that caffeine reduces the rate of perceived exertion during exercise, suggesting that athletes are able to sustain higher intensities but do not perceive this effort to be different from placebo conditions.
Products
Beverages
Chocolate derived from cocoa beans contains a small amount of caffeine. A typical 28-gram serving of a milk chocolate bar has about as much caffeine as a cup of decaffeinated coffee. By weight, dark chocolate has one to two times the amount of caffeine as coffee: 80–160 mg per 100 g.
Tablets offer the advantages over coffee and tea of convenience, known dosage, and avoiding concomitant sugar, acid and fluid intake. Manufacturers of caffeine tablets claim that using caffeine of pharmaceutical quality improves mental alertness.
- Coffee. The world's primary source of caffeine is the coffee "bean", from which coffee is brewed. In general, one serving of coffee ranges from 80-100 mg, for a single shot (30 milliliters) of espresso, to approximately 100–125 mg for a cup (120 milliliters) of drip coffee.
- Tea. Tea contains more caffeine than coffee by dry weight. A typical serving, however, contains much less, since tea is normally brewed more weakly than coffee.
- Soft drinks and energy drinks. Caffeine is a common ingredient of soft drinks, such as cola, which typically up to 55 mg of caffeine per 12 ounce serving. By contrast, energy drinks, such as Red Bull, can start at 80 mg of caffeine per serving.
- Mate. As a traditional South American caffeine-rich infused drink, Mate was first consumed by the indigenous Guaraní.
Chocolate derived from cocoa beans contains a small amount of caffeine. A typical 28-gram serving of a milk chocolate bar has about as much caffeine as a cup of decaffeinated coffee. By weight, dark chocolate has one to two times the amount of caffeine as coffee: 80–160 mg per 100 g.
Tablets offer the advantages over coffee and tea of convenience, known dosage, and avoiding concomitant sugar, acid and fluid intake. Manufacturers of caffeine tablets claim that using caffeine of pharmaceutical quality improves mental alertness.
Fasting From Caffeine
Giving up a heavy addiction to caffeine can involve withdrawal symptoms not unlike those experienced by cocaine addicts: headache, irritability, lethargy, nervousness, depression, and even drug-seeking behavior are not at all uncommon. Fasting from caffeine also allows the body to replenish and restore the adrenal glands. The release of adrenaline will readjust itself overtime, becoming more naturally in tune with the needs of life, as regulated by the brain rather than a cup of coffee; your wise, innate physiology will naturally find the appropriate amount for each circumstance that arises in your day. Your body will be able to process the excess adrenaline stored in your muscles, leading to a greater sense of well-being, release of muscle tension and spasms, and fewer tension headaches. If you choose to reuse caffeine after fasting, by becoming caffeine-naive, your body will recalibrate itself, and will require less caffeine for the desired effect. Furthermore, you may find you have more energy than before, and no longer require a coffee to get you through the day.
Coffee has become a crutch to wake us up and get us through the day. If this is the case for you, it may be best to examine that. If you need stimulants to give you an energy boost, something is wrong with your body. You are not producing your own natural energy and are supplementing with caffeine.
Another issue with caffeine is that it slows the body's endogenous detoxification process. If you are open to wean off caffeine and cut back to just one small cup in the morning and reap the benefits of natural energy and enhanced detoxification, consider the following protocol.
Coffee has become a crutch to wake us up and get us through the day. If this is the case for you, it may be best to examine that. If you need stimulants to give you an energy boost, something is wrong with your body. You are not producing your own natural energy and are supplementing with caffeine.
Another issue with caffeine is that it slows the body's endogenous detoxification process. If you are open to wean off caffeine and cut back to just one small cup in the morning and reap the benefits of natural energy and enhanced detoxification, consider the following protocol.
How to wean off caffeine
- Week 1: Make the same size coffee, but use 1/2 decaf
- Week 2: Move down 1 size coffee and stay with 1/2 decaf
- Week 3: Move to just a small coffee, 1/2 decaf, or all decaf
- Week 4 and beyond: Maintain with one small coffee or switch to green or herbal tea
Decaffeinated coffee, and caffeinated for that matter, should always be organic, and ideally Swiss water processed (decaf) to avoid toxins. Due to the half life of caffeine and its influence of natural cortisol rhythms, consume your coffee beverage before 1:00pm every day. This weaning protocol is well established to help people wean of all types of caffeine without the withdrawal symptoms. Just because a food or drink is enjoyable does not mean it needs to be rationalized why it is good. This happens with coffee far too more than it should.
References
Fisone, G., Borgkvist, A., & Usiello, A. (2004). Caffeine as a psychomotor stimulant: Mechanism of action. Cellular and Molecular Life Sciences, 61(7-8), 857-72. http://dx.doi.org/10.1007/s00018-003-3269-3
Freston, K. (2008). Quantum Wellness. New York: Weinstein Books
Pesta, D., Angadi, S., Burtscher, M. and Roberts, C. (2013). The effects of caffeine, nicotine, ethanol, and tetrahydrocannabinol on exercise performance. Nutrition & Metabolism, 10(1), p.71. https://doi.org/10.1186/1743-7075-10-71
Winston, A., Hardwick, E. and Jaberi, N. (2005). Neuropsychiatric effects of caffeine. Advances in Psychiatric Treatment, 11(06), pp.432-439. https://doi.org/10.1192/apt.11.6.432
Freston, K. (2008). Quantum Wellness. New York: Weinstein Books
Pesta, D., Angadi, S., Burtscher, M. and Roberts, C. (2013). The effects of caffeine, nicotine, ethanol, and tetrahydrocannabinol on exercise performance. Nutrition & Metabolism, 10(1), p.71. https://doi.org/10.1186/1743-7075-10-71
Winston, A., Hardwick, E. and Jaberi, N. (2005). Neuropsychiatric effects of caffeine. Advances in Psychiatric Treatment, 11(06), pp.432-439. https://doi.org/10.1192/apt.11.6.432
