No doubt about it - the caffeine in tea, coffee, soft drinks and caffeine pills are the world's most popular drug. The origins of the words, coffee and caffeine, reflect the spread of the beverage into Europe from north-east Africa, where coffee plants were cultivated in the 6th century. In Europe, coffee began to be popular after 9 centuries. Mainly, caffeine sources are coffee and tea. However, there are also many other caffeine sources such as chocolate, energy drink, soft drink, which contain too little quantity of caffeine for creating effects that can be on part with tea or coffee.

Coffee and tea are the most spread dietary caffeine sources with adults, and at the same time soft drinks are the huge caffeine source for children. Usually, a number of drinks, such us orange soda and cream soda, root beer (non-cola dinks) contain a similar quantity of caffeine which can be found in cola drinks. Also, some yogurts and sorts of coffee ice cream deliver a significant quantity of caffeine.

Cocoa and chocolate milk are caffeine sources, too. Cups of coffee contain about 75 mg caffeine, but that varies according to the method of preparation, to cup size and the amount of coffee used. A cup of tea averages 30 mg, but the range is also large from 10 to 90 mg. Other caffeine sources, such as cola drinks, contain about 35 mg caffeine, per standard 280 ml serving; a cup of hot chocolate contains about 4 mg caffeine; and a 50-gram chocolate bar between 5 and 60 mg, increasing with the quality of the chocolate.

Caffeine is completely absorbed from the stomach and small intestine, within 45 minutes of ingestion. But, unlike alcohol, effects of such caffeine are short-lived. Generally, in dark roast coffee, there is less caffeine than in lighter roast, because since the process of roasting the caffeine from the bean is reduced considerably.

Another caffeine source - tea -- contains somewhat less of a dose of caffeine than coffee, in dependence of the strength of the process of brew. However, there are several sorts of tea, for example oolong and black, which contain more caffeine. It is not a rule, that caffeine in tea and coffee, caffeine pills, are negative effects for mental functions and, usually, caffeinated drinks are frequently consumed. However, it is much recommended to limit using of caffeine in tea and coffee, caffeine pills, which lead to dependence.

Otherwise, the dropping of blood pressure can lead to headache, which affects at least of 50 percent of people are in caffeine withdrawal. 250 mg caffeine per day can provoke insomnia, restlessness, nervousness, depression, gastrointestinal problems or hallucinations. Bat more than 1000 mg per day can provoke cardiac, speech, thought and behavioral problems.

Experts have shown that caffeine in tea and coffee, soft drinks and caffeine pills, may lead to miscarriage or may slow the growth of a developing fetus. Furthermore, the use of large amounts of caffeine by the pregnant women may lead to cardiac problems of the unborn child. In this way, the best advice is to reduce or eliminate caffeine use in our daily life.