What is Caffeine?
Caffeine is one of the most popular stimulants that is consumed in the world. It is ubiquitous in all cultures with its benefits seemingly felt by all that use it. The chemical name of caffeine is 1, 3, 7-trimethylxanthine with a chemical formula of C8H10N4O2. Broadly, its psychoactive properties are known to improve awareness and act as a promoter of cognitive and physical performance. Despite the FDA’s classification of caffeine as a safe drug, it has the typical pharmacological properties of any other drug where the consumer can develop dependence (and withdrawal), have variable responsiveness to caffeine, and can become sensitized to the effects of caffeine.
The effects of caffeine are well-studied and have been documented throughout history. The origins of caffeine can be traced back to China around 1000 BCE where tea leaves were boiled to create a tea. Caffeine from coffee is thought to be discovered later in Ethiopia around 850 BCE. The origins of the term caffeine comes from the German word Kaffein. This term came from the German scientist, Friedlieb Ferdinand Runge, who first isolated caffeine in the early 1800s and called it Kaffebase.
Research into the exercise performance benefits of caffeine started around the 1940s in Denmark and the United States. Key studies investigating the benefits of caffeine during endurance exercise occurred in the 1970s at the Ball State Human Performance Laboratory.
Because coffee and caffeine were recognized as having stimulatory effects, it was regulated by early societies and even in more modern competition. The Ottoman empire restricted coffee for certain classes in the 16th century while the use of caffeine was restricted between 1984-2004 by the World Anti-Doping Agency.
Sources and Manufacturing
Caffeine is found to be naturally occurring (e.g. coffee beans, matcha) and synthesized through commercial processes. There are several ways in which natural caffeine extraction occurs, but the most common is through the use of chemical solvents such as liquid carbon dioxide. This “decaffeination” process is used to remove caffeine in the tea leaves or coffee beans, for example, before being purified and used. Synthetic caffeine production begins with ammonia or urea. While there are several ways which synthetic caffeine can be produced, all methods require a series of complex chemical processes. Once synthesized, the caffeine is purified before being used.
Synthetic and natural caffeine are chemically identical and difficult to distinguish otherwise. However, some individuals may experience synthetic and natural caffeine differently. This is most likely due to the other substances in the drink or food that may modulate the way the consumer experiences synthetic and natural caffeine. For example, the inclusion of nootropics (e.g. taurine) and sugars can enhance the ergogenic effects of caffeine.
Caffeine can be found naturally occurring in drinks such as teas and coffee or added during production in the case of sodas and energy drinks. Amounts of caffeine are variable in different foods and beverages. For example, a cup of coffee can have a range of 75-200 milligrams of caffeine depending on the size of the cup. A cup of tea can contain between 15-75mg of caffeine depending on the type of tea and size of the serving. Maté is another popular South American beverage that can contain 70-80mg of caffeine.
Qualities
Physiological effects
Caffeine has substantial impacts throughout the various physiological systems in the body (e.g. nervous, cardiovascular, and renal systems). It is quickly absorbed by the GI tract after consumption with the majority being absorbed within 30-120 minutes. Peak concentrations are achieved in the blood depending on the factors that impact absorption such as a previous meal. Absorption times can be further improved through gum containing caffeine whereby absorption via the oral mucosa can occur. Most of the ingested caffeine will be metabolized in the liver. The half life of caffeine is highly variable between individuals and can range between 1.5 to 10 hours. The rate at which caffeine is metabolized is also influenced by the environment and genetics (i.e. the CYP1A2 and ADORA2A genes) of an individual.
Caffeine can easily cross the blood-brain-barrier due to its molecular properties. In the brain, caffeine functions by blocking a specific receptor called the adenosine receptor. Blocking this receptor has been found to prevent the fatigue that is caused when adenosine binds to these receptors. As a result, this leads to delayed fatigue and increased awareness. Release of adrenaline from the adrenal gland is also increased with caffeine.
Caffeine is also known to stimulate the breakdown of triglycerides (lipolysis) and increase the amount of free fatty acids and glycerol available to the muscle to use as an energy source. This occurs directly from the impacts of caffeine, but also from the increased presence of adrenaline. Subsequently, it is thought that the use of muscle glycogen is spared.
In the muscle, caffeine has been found to increase calcium sensitivity, decrease calcium reuptake, and increase calcium release, which may increase the contractile performance of skeletal muscle.
In the heart, the increased presence of adrenaline in the body results in the increase in heart rate. At rest or exercise, moderate amounts have no particular impact on an individual’s physiological stability, rather a side effect of caffeine ingestion. However, excessive ingestion of caffeine can lead to arrhythmias.
In the kidneys, caffeine acts as a diuretic causing the increased production of urine. It is also known to stimulate bowel movements. At rest or exercise, moderate amounts have no particular impact on an individual’s physiological stability, rather a side effect of caffeine ingestion. However, excessive ingestion of caffeine can lead to dehydration due to the diuretic effects. Furthermore, in competitive environments these impacts can be rather bothersome prior to or during competition.
We further discuss the the physiological and performance benefits of caffeine here
Appearance and taste
Caffeine is perceived to have a bitter taste. Due to this flavor profile, the bitterness is easily identifiable in the foods and beverages that contain caffeine. When isolated, caffeine appears as a white crystalline powder.
Other uses
Other non-traditional uses of caffeine include its implementation in medical settings to manage disease symptoms such as respiratory conditions, neurological conditions, and some post-surgery therapy. In plants, the naturally occuring caffeine can act as an insecticide, thus prolonging a plants ability to survive.
Caffeine in Carbs Fuel Products
The primary role of caffeine in Carbs Fuel products is to provide additional performance benefits that are desired during exercise. Caffeine is found in the Carbs Fuel Caffeinated Original Energy Gel in the amount of 100mg per gel. This amount is sufficient for most individuals to experience the benefits from caffeine that is helpful for performance at a psychological and physiological level during workouts and races. Some individuals may need more depending on their caffeine sensitivity.
