Caffeine is a natural stimulant found in coffee, tea, chocolate, and various other beverages and foods. Research on caffeine mainly focuses on its effects on the central nervous system, including its ability to increase alertness, improve cognitive function, and enhance physical performance. Studies also explore its potential health effects, such as its role in reducing the risk of certain diseases or its impact on sleep patterns and anxiety levels. Overall, research on caffeine continues to uncover both its benefits and potential risks, leading to ongoing discussions about its consumption in various forms and quantities.