Caffeine is a natural chemical which has stimulant effect. It belongs to the class of compounds called xanthines and one of mostly used compound in world. Caffeine acts on the central nervous system and can temporarily ward off drowsiness and restore alertness. caffeine blocks the action of adenosine, a neurotransmitter that promotes sleep and relaxation and increases the levels of other neurotransmitters like dopamine and norepinephrine, leading to enhanced alertness, improved mood, and increased energy levels.

Caffeine is found in various plants, most notably in coffee beans, tea leaves, cacao beans (used to make chocolate), and kola nuts. The caffeine content can vary based on factors like the brand, brewing or processing methods, and individual variations. Usually, brewed Coffee contains around 95 mg per 8 oz cup, Black Tea contains 40-70 mg per 8 oz cup and Green Tea contains 20-45 mg per 8 oz cup. A cup of hot chocolate contain 7.44mg of caffeine while a cup of brewed coffee contain 95mg. However, Coffee is widely popular in many parts of the world, and it is a major source of caffeine for millions of people. It is particularly prevalent in Western countries, with a strong coffee culture in places like Europe, North America, and South America while Tea is also a globally consumed beverage and is particularly popular in countries such as China, India, Japan, and various regions in the Middle East.

Common sources of caffeine include coffee, tea, cocoa, energy drinks, sodas, soft drinks and certain medications. Caffeine is a central nervous system stimulant that can enhance alertness. Caffeine can stimulate the release of adrenaline, which may improve physical performance by increasing heart rate, mobilizing fatty acids from the fat tissues, and enhancing endurance. As well as it contains antioxidants that may help neutralize harmful free radicals in the body, potentially reducing oxidative stress. Caffeine can influence the release of neurotransmitters like dopamine and serotonin, contributing to improved mood and a sense of well-being. According to some studies, moderate caffeine consumption may be associated with a reduced risk of certain diseases, such as Parkinson’s disease, Alzheimer’s disease, and certain types of cancers. Caffeine has been linked to better cognitive function, including improved memory, reaction time, and overall cognitive performance. Caffeine is sometimes included in over-the-counter pain relievers, as it can enhance the effectiveness of certain medications and provide relief from headaches. Caffeine can temporarily boost metabolic rate and increase fat burning, making it a common ingredient in some weight loss supplements. Some studies suggest that regular, moderate caffeine consumption may be associated with a decreased risk of developing type 2 diabetes and lower risk of strokes.

Recommended caffeine intake varies based on factors such as age, health status, and individual sensitivity to caffeine. According to FDA 400 milligrams of caffeine per day as a generally safe amount for most healthy adults. Pregnant individuals are advised to limit their caffeine intake to 200 milligrams per day. Excessive consumption of caffeine can cause adverse health effects. Caffeine is a stimulant that can interfere with sleep by blocking the effects of adenosine, a neurotransmitter that promotes relaxation and sleep. Consuming caffeine, especially in the evening, can lead to difficulty falling asleep and disrupted sleep patterns and causing disorders like insomnia. High doses of caffeine can cause a temporary increase in heart rate and blood pressure. This effect may be more pronounced in individuals who are not regular caffeine consumers. Excessive caffeine intake can lead to digestive problems such as acid reflux, stomach upset, gastrointestinal discomfort and feelings of restlessness and nervousness. While caffeine can sometimes relieve headaches, excessive consumption or sudden withdrawal can lead to headaches or migraines. Regular consumption of large amounts of caffeine can lead to dependency, and abrupt cessation can result in withdrawal symptoms such as irritability, fatigue, and headaches. Excessive caffeine intake may interfere with calcium absorption, potentially increasing the risk of osteoporosis, especially in individuals with low calcium intake. As well as pregnancy related risks also possible.