Caffeine is a stimulant. It is a naturally occurring chemical found in coffee beans and other foods, drinks, and medicines. It can also be artificially synthesized for use in certain medicines. Consumption of caffeine increases alertness and activates the nervous system, temporarily warding off drowsiness and restoring mental alertness. This effect begins approximately 15 minutes after consumption but may take up to 2 hours before experiencing a full effect.According to Cleveland Clinic, caffeine has a half life upto 6 hours. That means that after consuming caffeine at 8 AM one morning it could potentially take you until 2pm before the body eliminates 50% of it!Caffeine was approved as a food additive in 1958 because it has been found to dissolve easily in water and mix well with other ingredients. Caffeine is often associated with coffee, due to its high concentration in coffee beans.However, caffeine can be found in other ingredients that are commonly added to many products consumed every day including tea leaves, guarana seeds, cocoa beans, kola nuts, and yerba mate leaves. These are all considered dietary supplements because they contain naturally occurring levels of caffeine.