I do not consume caffeine 
How come? It's the world's most widely consumed psychoactive drug.
I think I am just really sensitive to it. It makes me jumpy.
Ah yes, caffeine stimulates certain portions of the autonomic nervous system.
I wonder how long it has been around
I'm not sure, but caffeine is legal and unregulated in nearly all parts of the world.
I see some people drinking a few energy drinks a day. I think that is somewhat unhealthy.
Energy drink
An energy drink is a type of drink containing sugar and stimulant compounds, usually caffeine, which is marketed as providing mental and physical stimulation (marketed as "energy", but distinct from food energy). They may or may not be carbonated and may also contain other sweeteners, herbal extracts, taurine, and amino acids. They are a subset of the larger group of energy products, which includes bars and gels, and distinct from sports drinks, which are advertised to enhance sports performance. There are
Caffeine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is the world's most widely consumed psychoactive drug. Unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world. There are several known mechanisms of action to explain the effects of caffeine. The most prominent is that it reversibly blocks the action of adenosine on its receptor and consequently prevents the onset of drowsiness induced by adenosine. Caffeine also stimulates certain portions of the autonomic nervous system.
Caffeine