What Is Caffeine Exactly?


Definition caffeine

According to the Nutrition Encyclopedia caffeine is

“a naturally occurring stimulant found in the leaves, seeds, or fruit of over sixty plants around the world. It exists in the coffee bean in Arabia, the tea leaf in China, the kola nut in West Africa, and the cocoa bean in Mexico”.

No matter how remote a place, it’s used almost everywhere making it the most widely used psychoactive substance in the world. The most common sources in North America and Europa are coffee and tea.

caffeine“Since about 1980, extensive research has been conducted on how it affects health.

Most experts agree that moderate use (300 milligrams, or about three cups of coffee, per day) is not likely to cause health problems”.


On average, the following amounts of this ingredient can be found in a cup or bar:

  • ground coffee            90
  • instant coffee             60
  • decaffeinated coffee  3
  • tea                             40
  • cola                            40
  • chocolate bar             40

Ok, so we can find it in tea….but does that include all teas? More specifically, (…since we are on the Green Tea Paradise website), can you find it in your cup of green tea? Find out here: caffeine in green tea.

Side effects

Sometimes also called theanine when found in tea, this stimulant keeps you and your body alert so you can focus better and get things done.

However, side effects may occur when the so-called drug is taken in too large doses (more than six cups of coffee a day):

  • nervousness
  • sweating
  • tenseness
  • upset stomach
  • anxiety, and
  • insomnia.

This substance can also prevent clear thinking and increase the side effects of certain medications.

Check out all possible SIDE EFFECTS of the stimulant here……

DECAFFEINATED green tea: it’s not all glitter and glamour.

Return from caffeine to the HOME page.


Nutrition Encyclopedia, Nutrition and Well-Being A-Z, edited by Delores C.S. James, The Gale Group Inc.