Will Drinking Tea Cause Insomnia? Unveiling the Caffeine Content in Different Tea Types

While drinking tea brings pleasure, the varying caffeine content in different teas may lead to insomnia, making it crucial to choose the right type of tea. For many tea lovers, the worry of insomnia often accompanies their tea enjoyment. In fact, selecting the appropriate tea type is essential, as the caffeine content varies significantly across different teas.

There is a common misconception that green tea contains the highest caffeine. This might be a widespread misunderstanding. Green tea is not necessarily the highest in caffeine, as the caffeine content varies greatly among different tea types—an important fact to understand. According to the latest research, a surprising ranking is about to be revealed, and green tea might not be the "king of caffeine."

 

The Origin and Protective Role of Caffeine

Caffeine, a component both beloved and feared, where does it come from? Caffeine is a self-protective component of the tea plant, found in higher concentrations in tender buds to resist pests and diseases. In tea plants, tender buds, due to their rapid growth and fragility, require more protection, making their caffeine content generally higher than that of older leaves.

Fermentation and Caffeine Content

The caffeine content in tea is not solely determined by the tea variety and growing environment but is also influenced by many other factors. It is often mistakenly believed that fully fermented teas, such as black tea, experience a reduction in caffeine during fermentation. However, fermentation primarily affects polyphenols and has little impact on caffeine content.

Processing Techniques and Brewing Methods

Tea processing techniques, including rolling and roasting, can affect caffeine content and release. The intensity of rolling and the temperature of roasting influence caffeine levels, while water temperature and steeping time affect its solubility. During rolling, the degree of force directly determines the extent of cell rupture, which in turn affects the amount of caffeine extracted.

Caffeine Content in the Six Major Tea Types (Measured per 240ml Cup)

Black Tea

Black tea has relatively high caffeine content among the six major tea types, generally ranging from 25-110mg per cup. As a fully fermented tea produced through a series of processes, black tea contains higher caffeine. Commonly consumed varieties include Dian Hong, Lapsang Souchong, and Jin Jun Mei. Jin Jun Mei contains about 55mg per cup, while Keemun black tea has about 48mg. Fully fermented black teas made from tender buds tend to have higher caffeine content. Notably, Jin Jun Mei has higher caffeine content than Dian Hong.

 

Oolong Tea

Oolong tea has moderate caffeine content, generally ranging from 12-55mg per cup. Oolong tea, also known as "blue tea," is a semi-fermented tea with many varieties, such as Phoenix Dan Cong, Tie Guan Yin, and Da Hong Pao. Tie Guan Yin contains about 38mg per cup, while Da Hong Pao has as much as 42mg. The semi-fermentation process of oolong tea retains more caffeine, and the intense rolling promotes its full extraction.

 

Green Tea

Green tea has relatively low caffeine content, generally ranging from 8-50mg per cup. As a non-fermented tea, green tea retains more natural compounds and typically contains lower caffeine. Commonly consumed varieties include Zhu Ye Qing, Bi Luo Chun, and West Lake Longjing. Premium Longjing tea contains about 40mg per cup, while Jiangsu Bi Luo Chun has about 48mg. The high-temperature fixation process in green tea locks in the caffeine from tender buds, with caffeine content proportional to the tenderness of the leaves.

Dark Tea (Heicha)

Dark tea and Pu-erh tea are post-fermented teas, and drinking them does not cause insomnia. Compared to green and black tea, the caffeine content in dark tea is significantly lower, and most of it sublimates and evaporates during the high-temperature roasting process. On average, a cup of dark tea contains about 8-15mg of caffeine. Recommended dark teas include Anhua dark tea, Liubao tea, and ripe Pu-erh tea.

Yellow Tea

Yellow tea is known for its unique "men huang" (sealed yellowing) process, which causes some decomposition of caffeine. Huoshan Huangya, after processing, loses a significant amount of caffeine, containing about 28mg per cup. Although yellow tea is made from tender buds, its processing leads to greater caffeine loss compared to green tea.

White Tea

Bai Hao Yin Zhen contains about 37mg of caffeine per cup, while Fuding Bai Mu Dan has about 30mg. The non-roasted and non-rolled processing of white tea preserves caffeine, with the bud tips particularly rich in it, making Bai Hao Yin Zhen relatively high in caffeine.

Recommendations for Choosing Tea

For Sensitive Individuals

For those prone to insomnia or sensitive to caffeine, dark tea and ripe Pu-erh tea are ideal choices. They have low caffeine content and are suitable for people who easily experience insomnia. Ripe Pu-erh tea also contains GABA, a component that aids sleep.

Timing Strategies for Drinking Tea

After waking up in the morning, it’s best to have some food first, rest for a while, and then enjoy a cup of white or black tea to quickly refresh and awaken the mind. After dinner, consider choosing an aged white tea or a roasted oolong tea to help relax the body and mind.

Reducing Caffeine Intake

Caffeine is released relatively quickly within the first 10 seconds of brewing, with about 70% rapidly dissolving. To reduce caffeine intake, you can try cold brewing or rinsing the tea leaves with warm water first, which can reduce caffeine by about 30% or partially, respectively.

Conclusion

The freedom to enjoy tea starts with understanding caffeine. The key is to know the caffeine content of different tea types, make reasonable choices and pairings, and enjoy a healthy tea-drinking lifestyle. There’s no need to fear the higher caffeine content in black tea—moderate caffeine intake is beneficial to health.