Caffeine

Definition

Caffeine is a natural stimulant most commonly found in tea, coffee, and various energy drinks. It works by stimulating the central nervous system to increase alertness and reduce fatigue.

5 Must Know Facts For Your Next Test

1. Caffeine is absorbed quickly from the gastrointestinal tract and distributed throughout body tissues.
2. It can cross the blood-brain barrier, impacting neurological function by blocking adenosine receptors in the brain.
3. Regular consumption of caffeine can lead to tolerance, dependence, and withdrawal symptoms.
4. High doses of caffeine can increase heart rate and blood pressure, potentially impacting cardiovascular health.
5. Caffeine metabolism primarily occurs in the liver through cytochrome P450 enzymes.

Review Questions

• How does caffeine affect the central nervous system?
• What are the potential cardiovascular impacts of high caffeine consumption?
• Where does the primary metabolism of caffeine occur within the body?

Related terms

Adenosine: A neurotransmitter that promotes sleep and relaxation by slowing down nerve activity.

Cytochrome P450: A family of liver enzymes responsible for metabolizing various substances including drugs and toxins.

Withdrawal Symptoms: Physical or psychological effects that occur after stopping or reducing intake of a substance to which one has developed dependence.