Disputes about where is the more caffeine - in tea or coffee ― do not stop for many years. History will help us to reply to this question. In 1827, it was discovered that tea contains caffeine, which was named theine. As it turned out later, caffeine and theine are identical. Another significant discovery was the fact that in a cup of tea contains about ½ or 1/3 of the servings of caffeine, which accounts for a cup of coffee. However, when examined coffee and tea in a dry form, it became clear that the latter contains more caffeine.
In general, the amount of caffeine in tea depends on factors such as plant variety, harvest time, leaf processing techniques, storage, etc. The earlier it was harvested, the less caffeine is in tea leaves. Even such important caveat as the size of the leaves is significant. Tea is richer with alkaloid if a its leaves are smaller. Many people mistakenly believe that black tea contains more caffeine than green tea. In fact, recent studies suggest that the alkaloid content of green tea in a bag on average more than 71 mg. While in black tea, this figure was the highest. Also, test results showed that green tea with no flavor contains more caffeine. A cup of this drink contains amount exceeded 80 mg. This is given the fact that the weight of the tea bag is only 1.5-2 mg.
Caffeine is a kind of methylxanthines, which are contained in 60-plus plant foods. From a medical point of view of psychomotor stimulant caffeine is capable of exciting the nervous system, increase mental alertness, fight fatigue and sleepiness. In addition to the central nervous system, autonomic system is excited. The heart rate increases, along with the blood pressure. Thermo genesis is another feature of caffeine. Instead of keeping the calories as fat, the body begins to burn them. The muscles get the fuel at the same time and their performance increases. That's why many diets recommend drinking plenty of green tea.
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