Caféine

Caféine cover

Caffeine is a central nervous system stimulant of the methylxanthine class. It is the world's most widely consumed psychoactive drug. Unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world. Caffeine is found in the seeds, nuts, or leaves of a number of plants native to Africa, East Asia, and South America, and helps to protect them against predator insects and to prevent germination of nearby seeds. The most well-known source of caffeine is the coffee bean, the seed of the Coffea plant. People may drink beverages containing caffeine to relieve or prevent drowsiness and to improve concentration and focus.

Sources[edit | edit source]

Caffeine is naturally found in the leaves, seeds, or fruits of more than 60 plants. The most common sources of caffeine are coffee, tea (from the Camellia sinensis plant), yerba mate, cola nuts, guarana, and cacao pods. Synthetic caffeine is also added to some foods, beverages, and medications.

Chemical Properties[edit | edit source]

Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is soluble in water and organic solvents.

Mechanism of Action[edit | edit source]

Caffeine acts by antagonizing the adenosine receptors in the brain. Adenosine is a neurotransmitter that promotes sleep and relaxation by slowing down nerve activity. Caffeine, by blocking the adenosine receptors, increases nerve activity and promotes alertness, wakefulness, and a reduced sense of fatigue.

Health Effects[edit | edit source]

Positive Effects[edit | edit source]

Moderate caffeine consumption can have several health benefits, including improved physical performance, enhanced brain function, and a lower risk of serious diseases like Type 2 diabetes, Parkinson's disease, and liver disease.

Negative Effects[edit | edit source]

However, excessive caffeine intake can lead to negative health effects such as insomnia, nervousness, restlessness, stomach irritation, nausea, and an increased heart rate. In some individuals, high doses can lead to caffeine dependency and withdrawal symptoms.

Regulation[edit | edit source]

The regulation of caffeine varies by country, with some having specific guidelines for caffeine content in foods and drinks, while others focus on labeling requirements.