caféïne

Caféine is a naturally occurring stimulant found in the leaves and beans of over 60 plant species. It is most commonly consumed through beverages like coffee, tea, and certain soft drinks, as well as in chocolate and some medications. Chemically, caféine is a methylxanthine alkaloid. It works by blocking adenosine, a neurotransmitter that promotes relaxation and sleepiness, leading to increased alertness and reduced fatigue. The effects of caféine typically begin within 15 to 45 minutes of consumption and can last for several hours. Individual responses to caféine vary due to factors such as genetics, body weight, and regular consumption habits. While moderate consumption is generally considered safe for most adults and can offer benefits like improved concentration and physical performance, excessive intake can lead to side effects such as anxiety, insomnia, rapid heart rate, and digestive issues. Regular users may develop a tolerance, requiring higher doses for the same effects and experiencing withdrawal symptoms like headaches and irritability if consumption is stopped abruptly. Caféine is metabolized in the liver and excreted from the body.