1. What is it and where does it come from?

Caffeine is an alkaloid; of which there are numerous compounds such as the methylxanthines, with three distinguished compounds: caffeine, theophylline, and theobromine, found in guarana, kola nuts, coffee, tea, cocoa beans, mate and other plants. These compounds have different biochemical effects, and are present in different ratios in the different plant sources.

Caffeine is one of the most popular stimulants on the globe. It is a powerful stimulant to the Central Nervous System. Moderate use seems to be desirable by all, male and female; although excessive use can produce undesirable effects. Caffeine was discovered in 1820. In 1838, it was found that theine, a substance in tea, was identical to caffeine. Six or so caffeine containing plants are used more worldwide as a beverage than any other plants and herbal materials put together. The many caffeinated natural plants are are: Coffee, Tea, Kola, Cocoa, and Guarana.

Caffeine is a power and energy accelerant! It's perfect to super energize your body for powerful workouts. This fast-acting substance delivers the right molecular structure to your energy systems for maximum energy and power output. Caffeine much like Ephedra acts to increase mental alertness and neurologically provide the surge you need to maximize your training. Not just a stimulant, this powerful substance reaches deep into the muscle cell to provide lasting power and delaying the onset of muscle fatigue.

So how does caffeine work to provide you with maximum energy support and increased endurance? Caffeine affects the CNS causing more alertness and allowing for more intense focus. The chemical structure of caffeine is very similar to that of adenine (a component of ATP, DNA, and cyclic AMP). Only the substituents are different. This helps explain caffeine's stimulating effects. It is really close to being an energy metabolite in and of itself! Because of the structural similarities, caffeine can slip right into adenosine receptors, keeping cyclic AMP active rather than it being broken down. When cyclic AMP breaks down, the body's energy supply decreases. Because caffeine fools the body into using enzymes to break it down instead, the cyclic AMP supply remains higher for longer. I bet you always wanted to know that.

It increases the potency of aspirin or other analgestics. The majority of caffeine is produced in decaffeinating coffee.
 

Well, this is an interesting question. Nobody really needs caffeine, but I once read an article that said if all of America were to stop drinking coffee or caffeine-containing soft drinks/beverages, productivity would fall by 70%. So, anyone who wants more alertness and a mental/physical boost could use a little caffeine safely. Anyone who doesn't want to drink coffee or soda could easily supplement their diets with an energy-enhancing supplement that contains caffeine. Deficiency is not an associated problem with caffeine because it is not an essential nutrient.
 

Nonpregnant adults should limit their intake to about 250mg per day. Pregnant women should be even more conservative with their intake. Moderation in all caffeine containing products is the basic rule of thumb for the positive attributes without the undesirable effects of taking too much.