Caffeine is a natural stimulant found in over 60 plants and is popular worldwide. The coffee, chocolate, and tea we often drink contain caffeine. It should be clear that the caffeine content in beverages varies depending on the composition and preparation method.

Although scientists believe that caffeine is safe, excessive consumption may always cause some concerns, and of course, drinking too much water can also cause problems.

Why do people pay extra attention to caffeine?

It is estimated that 80% of people in the world enjoy drinking coffee every day. Due to its stimulating effect on the human body, scientists believe that caffeine has many benefits for human health, such as enhancing alertness, improving exercise performance and emotions, and promoting metabolism. Both the US Department of Agriculture (USDA) and the European Food Safety Agency (EFSA) define safe caffeine intake as no more than 400 milligrams per day, no more than 200 milligrams per dose, or no more than 3 milligrams per kilogram of body weight.
However, consuming more than 500 milligrams of caffeine in a single dose may cause some problems. Scientists have pointed out that consuming a large amount of caffeine can lead to anxiety, restlessness, and insomnia. Some studies have shown that even frequent intake of caffeine in moderate amounts can lead to chronic headaches and migraines.
In addition, caffeine is considered to be mildly addictive, and some people may be more prone to developing dependence.
The caffeine content varies depending on the type of beverage and preparation method
Both tea and coffee contain caffeine, and its content varies greatly depending on the origin, type, and production method.
Generally speaking, tea contains 3.5% caffeine, while coffee beans have a caffeine content of 1.1% to 2.2%. From this perspective, it seems that the caffeine content in tea is higher. However, the process of brewing coffee uses hotter water, which extracts more caffeine from the coffee beans.
Moreover, people use more coffee beans than tea when drinking coffee. Therefore, a cup of brewed strong coffee usually contains more caffeine than a cup of tea.
The caffeine content also varies depending on the variety of tea
Black tea, green tea, and white tea are all made from tea tree leaves. The difference between them lies in the time of leaf picking and the degree of oxidation.
The leaves of black tea will be oxidized during the processing, while white tea and green tea will not. This gives black tea a unique and strong taste, and also causes more coffee to precipitate when brewing tea leaves with hot water.
A 237ml cup of black tea contains an average of 47 milligrams of caffeine, but it may also contain up to 90 milligrams of caffeine. That is to say, for a typical 500ml beverage on the market, filling it with black tea can contain up to 190 milligrams of caffeine. In contrast, the same 237ml cup of green tea contains only 20 to 45 milligrams of caffeine, while each cup of white tea contains 6 to 60 milligrams of caffeine.
The caffeine content in green tea powder is often higher, with about 1 gram of matcha powder per half teaspoon typically containing 35 milligrams of caffeine.
It should be noted that although herbal teas on the market do not contain caffeine, a 237ml cup of herbal tea still contains 12 milligrams of caffeine