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


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.

What else is Caffeine known as?
Note that Caffeine is also known as:
  • Coffee extract
  • Tea extract
  • 1 3 7-Trimethylxanthine
Caffeine should not be confused with:
  • Caffeic acid
Dosage information

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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