Caffeinecontaining

Caffeine-containing is a term used to describe substances, foods, beverages, or medicines that include caffeine, a central nervous system stimulant in the xanthine class. Caffeine occurs naturally in coffee beans, tea leaves, cacao beans, kola nuts, yerba mate, and guarana, and is added to a variety of products to enhance alertness or taste.

Common caffeine-containing products include coffee, black or green tea, soft drinks, energy drinks, chocolate, and certain medicines and dietary supplements. Caffeine content varies widely: brewed coffee typically contains about 80-100 mg per 8-ounce serving; tea generally provides 20-60 mg per 8 ounces; cola beverages around 30-40 mg per 12-ounce can; energy drinks often range from 70-200 mg per serving. Chocolate contains smaller amounts, increasing with cocoa intensity. Some medications and supplements contain added caffeine as an active ingredient or adjuvant.

Effects and metabolism: Caffeine acts as a stimulant, increasing alertness but potentially causing sleep disturbances, jitters, or rapid heartbeat in sensitive individuals. It is metabolized by the liver enzyme CYP1A2, with a typical half-life of about 3-5 hours in healthy adults. Clearance can be influenced by factors such as pregnancy, smoking, certain drugs, and genetic differences.

Safety and regulation: Labeling of caffeine content varies by country and product category. General guidance often cites up to about 400 mg per day for most healthy adults, with lower limits for pregnant individuals and younger people. People with certain medical conditions or taking specific medications should consult healthcare professionals about caffeine use and potential interactions.