Tea Caffeine Levels
Ah, the age old question: which tea has the most caffeine? A common misconception is that black tea has the highest amount of caffeine, however, the answer is much more complex.
To understand caffeine levels in tea, you must understand how tea is processed. Green, white, oolong, and black teas all come from the same plant: camellia sinensis (the tea plant). The difference in the teas has to do with when the leaves are harvested, and how the leaves are processed. This is the first way in which caffeine content varies in tea. For example, white tea leaves are harvested at a younger age, and are therefore higher in caffeine than older tea leaves. Additionally, black tea leaves are roasted for longer times than green tea leaves. The longer roasting time results in some caffeine loss.
However, this does not mean that all green teas have more caffeine than black teas. There are more factors that affect caffeine levels, such as steeping time. Green teas are steeped at lower temperatures for less time for optimal flavor, whereas black teas are steeped at higher temperatures for longer times. This gives more time for caffeine to steep into the final cup. In fact, if green tea is steeped in the same manner as black tea, it takes on a bitter flavor from the higher amount of caffeine being steeped into the cup.
Lastly, there are compounds called catechins that are found in tea. Catechins have many health benefits, but they also affect the way the human body experiences caffeine. Catechins bind to caffeine, making the resulting molecule more difficult to digest. This changes the caffeine experience, resulting in a longer, yet more mellow, payoff. Green tea has more catechins than black tea due to the oxidation process for black tea. This means black tea tends to feel more caffeinated than green tea because the caffeine-jitters and other side effects are more likely. This is also why green tea is marketed as a study or work-aid; the more controlled absorption of caffeine results in longer periods of heightened focus.
At the end of the day, the caffeine level in teas will vary depending on a number of factors. Tea drinking can be a deeply personal practice. Steep your tea in a way that feels right for you.
Sources:
Daniel. “Which Tea Has the Most Caffeine? (the Answer Will Surprise You).” Let's Drink Tea!, 9 Mar. 2023, https://www.letsdrinktea.com/tea-most-caffeine/.
Katada, Shun, et al. “Effect of Tea Catechins with Caffeine on Energy Expenditure in Middle-Aged Men and Women: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial.” European Journal of Nutrition, vol. 59, no. 3, 2019, pp. 1163–1170., https://doi.org/10.1007/s00394-019-01976-9.
Metzler, Kathryn. “Does Green Tea Have More Caffeine than Black Tea?” Saratoga Tea & Honey Co., Saratoga Tea & Honey Co., 3 June 2021, https://www.saratogateaandhoney.com/blogs/blog/does-green-tea-have-more-caffeine-than-black-tea.
