Caffeine is a naturally occurring stimulant present in coffee beans and tea leaves. Other sources of this widely used psychoactive substance include cocoa beans, energy drinks and some medications. Even in tea alone, the caffeine content varies substantially depending on its preparation, quantity and type. While it’s mostly considered safe, the effects of caffeine are also different for the people consuming it. Therefore, it becomes important to take a good look at this stimulant to decide which choice of tea a person should take.
Pros and Cons of Caffeine
At low doses, caffeine is beneficial for most people and makes them alert and energetic. Scientific evidence also suggests that a moderate amount of tea and coffee is all right and does not damage health. Some people are sensitive to caffeine, and few are unable to consume it at all. At high doses, it can weaken our adrenal glands and cause addiction over time.
Safe Levels of Caffeine
Toddlers should not be allowed to consume caffeinated drinks. Young children and pregnant women should have no more than 200mg a day. For the rest, moderate daily intake of caffeine is at 400mg/day or 4-5 cups of tea/coffee.
Caffeine Content in a Cup of Tea
1. Tea Leaves Type
The way that the leaves are made influences caffeine content- For example, broken leaves impart more than whole leaves.
2. Amount of Tea Leaves Used
More caffeine is released with more tea leaves added. Teabags contain a standard amount while in case of loose leaves, it depends on the brewer.
3. Brewing Time
More caffeine is released the longer time that the leaves stay in hot water.
4. Temperature of Water
Higher the temperature more is the caffeine released
5. Tea Varieties
Black, green and white leaves are dissimilar, despite coming from the same plant, mainly due to the difference in their time of harvest and oxidation level in leaves. Their caffeine content, along with herbal tea, is given as follows:
Black Tea Leaves
A cup of black tea on average contains 47mg of caffeine per cup (237ml). But depending upon its preparation, it can have as much as 90mg.
Green Tea Leaves
Green tea contains 20-45mg per cup. Matcha is a high-caffeine tea packing 35mg per half teaspoon.
White Tea Leaves
White tea can have 6-60mg/cup.
Herbal Tea Leaves
These are “caffeine-free” but can contain a negligible amount of caffeine depending upon the type of tea.
Caffeine Content in Tea vs Coffee
Tea leaves contain about 3% caffeine while coffee beans have half the amount. However, hotter water is used to brew coffee, which extracts more caffeine than tea. A cup of coffee on average has 100mg of caffeine per cup (237ml) but some preparations like espresso, latte etc. can have several times the amount.
People who are sensitive to caffeine can enjoy white tea and herbal tea or can brew high-caffeinated tea for shorter periods. Those who have heart disease and migraine, as well as pregnant women, can also enjoy these types of teas and limit their caffeine intake. Those who are fans of high-caffeinated drinks can enjoy black tea and green tea variants depending upon how much caffeine they want. However, to continue enjoying tea-drinking, it’s best not to exceed 400mg (5 cups) of caffeine everyday.