Caffeine
•Last Updated: February 1 2023
Caffeine is a stimulatory anti-sleep compound extracted from coffee beans. Habitual caffeine use leads to tolerance, which dulls several of caffeine’s effects.
Caffeine is most often used for
Last Updated: February 1 2023
What does caffeine do?
Caffeine comes from coffee beans, but it can also be synthesized in a laboratory. It has the same structure whether it’s in coffee, energy drinks, tea, or pills.
Caffeine is a powerful stimulant, and it can be used to improve physical strength and endurance. It is classified as a nootropic because it sensitizes neurons and provides mental stimulation.
Habitual caffeine use is also associated with a reduced risk of Alzheimer's disease, cirrhosis, and liver cancer.
Caffeine’s main mechanism concerns antagonizing adenosine receptors. Adenosine causes sedation and relaxation when it acts upon its receptors, located in the brain. Caffeine prevents this action and causes alertness and wakefulness. This inhibition of adenosine can influence the dopamine, serotonin, acetylcholine, and adrenaline systems.
For practical tips on the optimal use of caffeine, check out our Supplement Guides.
Note that Caffeine is also known as:
- Coffee extract
- Tea extract
- 1 3 7-Trimethylxanthine
Caffeine should not be confused with:
- Caffeic acid
Caffeine dosages should be tailored to individuals. If you are new to caffeine supplements, start with a 100mg dose. Typically, 200mg of caffeine is used for fat-burning supplementation, while higher doses of 3–6 mg/kg of body weight are typically used to increase strength.
Caffeine can be supplemented through popular beverages, like coffee, tea, and energy drinks, but it can also be taken in a pill form.
Many of caffeine’s effects, including fat burning, strength benefits, and euphoria, are subject to tolerance, and may not occur in people used to caffeine, no matter how large the dose is.
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There are benefits associated with chronic caffeine consumption, and there are benefits associated with acute caffeine consumption that fade with tolerance; if you like the latter, cycling is mandatory. If you like the former, cycling is not needed.
Chronic non-cycled caffeine consumption (in the form of coffee and tea, both of which contain many bioactive components in addition to caffeine) is associated with a reduced risk of several diseases, including Parkinson’s disease, type 2 diabetes, and chronic liver disease.[385] Caffeine consumption has also been shown to enhance performance on attention tasks, regardless of the participants’ caffeine consumption habits.[386] Clearly, cycling isn’t needed to obtain these benefits. So why cycle? The question usually comes up in the context of exercise performance enhancement...
Over the course of a day, you get sleepy as adenosine binds to A1 receptors in your brain. Caffeine blocks adenosine from binding, thus making you feel alert and also helping you feel better.
Caffeine is the most widely consumed psychoactive drug in the world, largely due to its mood-enhancing and stimulatory effects.
Despite widespread consumption, few people are actually aware of how caffeine works in the body.
We thought you might be interested in learning exactly how caffeine works in your body after you ingest it and it enters the brain.
But first: how adenosine makes you feel sleepy
The key player here is adenosine.
If you remember your high school biology, think of the lock-and-key model...
Case studies have linked energy drinks to adverse effects, especially on the cardiovascular system, but the overall risk of something bad happening is low and context-dependent.
The energy drink market is huge. In 2016, it was valued at $43 billion globally and $12 billion just in the United States, where it is expected to nearly double by 2025.
Figure 1: Energy drink market in the United States (revenue in billion dollars)
Between 2007 and 2017, population surveys reported that 58% of young Canadians,[397] 53% of US military personnel,[398] 51% of US college students,[399] and 35% of New Zealand adolescents[400] consumed energy drinks. In other words, a good chunk of the young population...
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