Caffeine is the worlds most widely used and legal psychoactive substance consumed in the form of coffee or tea. It can also be supplemented and is most well-known for its energy boosting and alertness-enhancing effects.
What is Caffeine?
Caffeine is by far the world’s most widely consumed legal stimulant used by millions of people daily for its short-term alertness and energy boosting effects. Technically, stimulants do not qualify by definition as Nootropics however the effects of Caffeine on mental performance and brain functioning has been extensively documented.
It is a member of the purine alkaloids known as methylxanthines (xanthines) that act as mild psychostimulants and are naturally present in coffee beans, cocoa beans, tea leaves, guarana berries, kola nuts and yerba mate.
Caffeine is also present in certain supplements, some over-the-counter medications such as cough syrups and in many food and drink products in different concentrations including energy drinks, teas, soft drinks, chocolate bars and energy bars.
According to The Food and Drug Administration, Caffeine is considered to be both a drug and food additive. It has several interesting mechanisms of action, most notably stimulating areas of the autonomic nervous system and inhibiting adenosine activity, a chemical that plays an important role in natural sleep schedules.
These actions are how it promotes feelings of less drowsiness and boosts alertness. Additionally, Caffeine increases levels of circulating Dopamine in the brain, in a similar way to that of cocaine, but to a weaker degree. This is a powerful natural chemical involved in activating pleasure centers in the brain and regulating executive functions like paying attention and staying focused on a task.
This article will discuss what caffeine does in the brain in more detail, the potential benefits and uses of caffeine supplementation and the associated side effects and daily dosage guidelines.
Caffeine Effects on the Brain
The key mechanism of action of Caffeine is that it acts as a replacement for adenosine, a chemical whose role is to promote sleepiness and suppress arousal by binding to these receptors in the brain, preventing this natural chemicals calming effect on the nervous system.
Adenosine acts as an inhibitory neurotransmitter that is released in response to prolonged neural activity in the arousal centers of the brain when we are awake. When adenosine binds to its specific receptors, it acts as the brains natural “braking” system, slowing down brain cell activity by regulating the transmission of signals to achieve a proper balance which leads to drowsiness and the eventual state of sleep.
When Caffeine is present in the system, it dominates and attaches to adenosine receptors since it is similar in molecular structure, to where adenosine is no longer recognized by the brain since caffeine is taking up all the receptors it would normally bind to, resulting in the opposite effect, promoting wakefulness.
Fewer available receptors for adenosine to do its inhibiting job results in promoting increased neural activity (thought to occur in specific areas of the brain involved in attention and concentration) and in turn, stimulates the pituitary gland to secrete hormones, influencing the production of adrenaline (epinephrine).
This is the “fight or flight hormone” that prepares the body for action, boosting blood delivery to muscles, dilating airways, increasing blood pressure and decreasing pain perception. This is also where we get the burst of energy and increased alertness.
In addition, when nerve cell activity in the brain is slowed down by adenosine, it causes blood vessels to dilate or widen which is thought to serve for proper oxygenation of this organ during sleep. When caffeine dominates these receptors, it is believed blood vessels in the brain constrict which is thought to help relieve migraines and why some medicines used to treat vascular headaches contain caffeine.
Finally, greater stimulation in the central nervous system and the brain encourages an increase in the release of neurotransmitters, especially a small rise in Dopamine an important “feel good” brain chemical which allows us to experience pleasure, reward and is a key factor in drive and mental focus.
Caffeine is believed to slow down the rate of reabsorption of Dopamine, manipulating its levels in the same way as cocaine or heroin but acting more as “a soft drug”. While this action is thought to create a perceived “addiction” it does not cause a large enough rise to create an imbalance in the brains reward circuits associated with addiction. For this reason, most experts do not consider caffeine to be a serious addiction.
Caffeine Supplement Uses
Caffeine, whether consumed through coffee or taken in supplement form is most commonly used to stay awake and alert. It is estimated that 1.6 billion cups of coffee are consumed daily worldwide and it is considered to be the most popular beverage after water.
There is also some evidence that caffeine supplements may provide ergogenic effects (enhancing physical performance) on muscle strength and power which may be why it is one of the most widely used substances among athletes.
Currently, the National Collegiate Athletic Association (NCAA) restricts the amount of caffeine allowed by athletes to no more than 15 mcg/ml in urine concentration which equates to 500mg or approximately six-eight cups of brewed coffee.
Caffeine is also a substance that has been the subject of a considerable amount of clinical research, according to the Natural Medicines Comprehensive Database, where oral use of caffeine is rated Effective by the NMCD for treating the following;
- Postoperative headaches
- Migraine headaches when taken in combination with aspirin or acetaminophen
- Tension headaches when combined with analgesics
The NMCD also rates oral use of caffeine as Likely Effective for mental alertness and Possibly Effective for asthma, hypotension (low blood pressure) in the elderly, neonatal apnea, decreasing the risk of developing Parkinson’s disease, lowering the risk of developing Type II diabetes, pain (when combined with pain relieving agents), reducing the risk of developing gallstone disease, weight loss and improving memory.
The FDA has only approved caffeine as an acceptable product for use in combination with analgesics for managing pain associated with tension headaches and migraines. It is not approved by the FDA to prevent or treat any other conditions and more research is needed to determine all efficacies of this substance.
Benefits of Caffeine Pills vs Coffee
Caffeine does not really differ structurally based on the source. This means, whether you are drinking it via coffee, tea, drinks containing caffeine or using caffeine pills or supplements made from caffeine, you will achieve the same resulting benefits.
The most notable among them, for most people, is that morning cup of coffee or afternoon energy drink that helps you feel more energized, alert, focused and productive. Of course, these effects are short-term and reduce in intensity with our second cup or drink.
It is known to stimulate areas of the brain that control attention and concentration. Caffeine increases levels of circulating Dopamine, a key “feel good” natural chemical that activates the pleasure centers in the brain and plays a role in reward-motivated behavior, memory and focus.
Getting caffeine from a drink or pill may simply be a question of personal preference. Some people who would like to achieve the benefits associated with caffeine but don’t like the taste or the added calories needed to blunt it or enhance it and may opt for caffeine pills.
Additionally, it may increase urine output regardless of the source but when you are “a coffee lover” drinking fluids frequently may lead to many more trips to the bathroom and inconvenience may be another reason why some people prefer it in pill form.
Overall, Caffeine is considered a powerful stimulant to be used in moderation and whether you are consuming it in a beverage, food or in pill form, you should not exceed a total daily amount of 400 mg. As a Nootropic, it is found in many preformulated stacks and is also an ingredient some people add to their own routine stack.
In particular, Caffeine in combination with L-Theanine a compound naturally found in green tea and other teas, is considered a great stack for beginners to Nootropics. They are popularly used together for their pronounced synergistic effects, that may help heighten the effects of caffeine while preventing the anxiety and jitteriness caffeine can sometimes cause.
Side Effects of Caffeine
Caffeine is considered to well tolerated and safe for healthy adults when taken in proper daily dosages but continuous and prolonged use can pose some potential side effects.
The half-life of caffeine is approximately 4-6 hours in healthy adults. Half-life refers to the amount of time it takes the quantity of a substance to be reduced to half its original amount. This means, when taking 300 mg of caffeine, which is equivalent to 3-4 cups of coffee or approximately 100-150 mg per cup, after 5 hrs, 150 mg of caffeine will still be active in your system.
Caffeine that is taken in pill form (within 100mg-300mg) is approximately equivalent to the sensation of drinking 2-4 cups of coffee and the effects may last for an hour or two. However, pill or powder form raises the risk of overdose and it is important to check the product label and not exceed 300-400mg in a day.
Daily dosages above this threshold may overstimulate or irritate your system and may lead to potential associated side effects and risks including difficulty falling asleep, nervousness, restlessness, rapid or irregular heartbeat, acid reflux, stomach discomfort, reduced calcium absorption leading to weaker bones, increased blood pressure, dizziness and headaches.
There is a concern that you can develop tolerance to caffeine when consumed daily which may drive users to chase the strength of the original effects and overuse it. Extremely high doses of caffeine are toxic and for people sensitive to caffeine, in some cases, it doesn’t take high dosages to produce unwanted side effects. It is important to stay within the daily recommended dosage guidelines and listen to your body.
Caffeine is a substance listed as GRAS (generally regarded as safe) by the FDA however not everyone has the same sensitivity to the effects of caffeine and dosages may vary. Most experts recommend that healthy adults should not exceed 400mg in total caffeine intake per day. This is equivalent to approximately 4 cups of coffee per day.
An eight-ounce cup of brewed coffee approximately equals 100-150 mg depending on how strong you make it. Tea has less caffeine depending on which one you are drinking. The highest content is in black tea (60-90 mg per cup) while green tea and white tea are on the lower end (30-70 mg per cup).
Keep in mind caffeine is also present in chocolate, soft drinks, energy drinks, some ice creams and even in coffee and chocolate flavored e-liquids in different amounts which should be taken into account as far as daily dosage. It is probably best to limit the amount of coffee, or tea you drink and not exceed two cups per day if you are adding any of the above.
If you are considering caffeine supplements, their dosages can vary and it is important to follow the manufacturer’s dosage guidelines listed on the bottle. In addition, Caffeine tolerance is a possibility, which means over time, your response to the effects of caffeine may weaken and you may want to consider cycling it if you are using it as a Nootropic.
Caffeine has been associated with boosting alertness, concentration, focus, attention, cognition and athletic performance but it is considered a stimulant drug. Whether your personal preference is consuming beverages that contain caffeine or taking caffeine pills or supplements, it should be taken in moderation and at proper dosages by healthy adults.
Users may choose to take caffeine in pill form as a more convenient or less costly method of getting the benefits of caffeine.
Whether you are considering caffeine pills as a pre-workout supplement, to get a burst of energy, for longer periods of concentration and wakefulness or as an alternative to coffee, taking caffeine when needed only, may be the best option to lessen the risks associated with over usage and tolerance.
When taken in moderation and weighing the risks and benefits, you can enjoy the full energy and brain-boosting effects that caffeine is known for.
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