Let’s start with a basic question of terminology. Sometimes you will read that tea contains caffeine, sometimes it’s called theïne instead. Theïne and caffeine are the same thing – but they work differently. In other words, tea and coffee both contain caffeine (or its chemical handle: 1,3,7-trimethylxanthine), but the caffeine in tea releases into the body differently and affects different parts of the body than does the caffeine in coffee. The differences are notable enough that it makes sense to use different names, caffeine and theïne, even though the chemical substance is the same. I’ll first cover those basic differences between caffeine in tea and coffee, below, then I’ll cover some differences strictly among different types of tea.
Coffee packs a stronger caffeine punch than tea, even though coffee beans contain proportionally less caffeine than tea leaves, roughly 1.1 to 2.2% per bean compared with about 3.5% per leaf. Those are very rough numbers, as the actual content of leaf or bean will vary with many factors, from the particular plant, to the environment in which it grows, to the season in which the leaf or bean is harvested. Even though all tea leaves come from the same genus of plant, the camellia sinensis, there will be variety in their caffeine content.
But so why is the effect of caffeine in tea milder than with coffee? For one, coffee delivers much more of the caffeine it contains into your cup than does tea. There are two main reasons for that. Caffeine is more soluble at higher temperatures, which means more caffeine will be released in the hotter water used to brew coffee. And the coffee bean is ground, which exposes and allows more caffeine into the brew.
The same principle applies for different teas also: a whole leaf tea, such as we sell at Amsterdam Teas, will release relatively less caffeine than a typical bag of tea, which usually contains leaves that have been chopped into small pieces using the CTC (or Cut, Tear, Curl) process. By contrast, matcha, for which the leaf is powdered and consumed entirely, will deliver a relatively high amount of caffeine. But for the reasons I’m about to explain about the chemical properties of tea, the caffeine from matcha – as with all teas – will have a very different effect from coffee, providing less of a jolt and more of a lift, if you know what I mean (and you probably do if you’ve had good tea).
So let me get to the reasons for the difference, which has to do with the chemical composition of the tea leaf. In tea, caffeine is bound up with other elements, commonly called tannins, also known as catechins. Catechins are polyphenols with binding properties and related, antioxidant effects. You can read more about these nutritional characteristics at our page on nutrition. With respect to caffeine, the tannins inhibit the release of the caffeine from the brew into the body. This means that the caffeine in a cup of tea releases more slowly, and takes more time to be absorbed into the body.
In part, the slow release of caffeine tea helps to explain another difference from caffeine in coffee, the one that I touched on with matcha, the lift versus the jolt. Caffeine from coffee goes straight to the coronary system and blood circulation, which accelerates the heart rate and causes that famous coffee rush. The slow release of caffeine from tea goes more to the cerebral cortex, with effects on the central nervous and cardiovascular systems. This gives tea the more gentle, cerebral stimulation with which it has been associated since its earliest consumption among the monks of China and Japan, where it has historically been linked with meditation practices. You can read more about these historical associations here and here.