I always enjoy good tea. This seems perfectly logical when you consider than I’m a British person living in Japan (apparently ocean island nations have a predisposition towards drinking tea). Interestingly though, it seems that tea is good for your brain…
This lovely little molecule is theanine. It was first isolated at the tea laboratory of Kyoto★ back in 1950, from a high grade type of Japanese tea called gyokuro♣︎. In fact, aside from a certain species of mushroom and an Amazon rainforest plant, this little molecule is only known to be found in tea (where it provides the nice rich umami flavour of many tea varieties).
Theanine does more than simply provide flavour, however. It can cross the blood-brain barrier and has mild psychoactive properties, being considered by many to be a nootropic – i.e., a chemical which improves brain function. Nootropics are compounds which can not only assist cognitive ability, but also act as protective agents for brain neurons. In humans, theanine has been implicated in alleviating physical and mental stress, boosting mood, and improving cognitive performance. While I don’t believe any proper large scale studies have been carried out yet, a number of smaller ones have evidently shown some success in proving this.
Theanine also acts synergistically with caffeine (arguably the most widely used nootropic in the world). The two together are apparently great for alertness and focus, which may explain why monks out here in East Asia have been using tea for centuries to aid their meditations. It may also have something to do with that old myth that tea contains more caffeine than coffee – for the record, a typically brewed cup of coffee most certainly contains more caffeine, but also contains no theanine at all (tea also contains a caffeine-like molecule called theophylline, but in such small quantities as to be practically non-existent).
Interestingly too, there seem to be no ill effects from theanine consumption. In fact, quite the opposite. While it acts synergistically with caffeine, it also serves to take the jittery edge off excessive caffeine consumption. Studies have even supported that it may have neuroprotective effects, helping to prevent memory impairment. Additionally, it can increase your dopamine levels, and promotes production of alpha waves.
A good reason to drink more tea, right? Well… The thing is, in most tea there isn’t a huge amount of theanine present. Most teas, both green and black, are relatively low in theanine, meaning that you’d need to drink an awful lot to see much effect♥︎. However, certain teas are particularly rich in theanine. In particular, the finer varieties of Japanese tea are shade-grown. Gyokuro (玉露) and matcha (抹茶) are shaded prior to harvesting, causing the leaves to develop a deeper colour. The tea bushes produce a greater amount of chlorophyll in their leaves, and start to produce a much higher concentration of amino acids. This gives these teas their unique flavour and aroma. It also yields a much higher level of theanine (itself a variety of amino acid). Those monks I was saying about before? In Japan, they were particularly fond of brewing matcha.
Matcha is something quintessentially Japanese, and it’s quite deeply ingrained into the culture over here. It’s used to give both flavour and a bright green colour to all sorts of things, from chocolate, to sweets, to ice cream. It’s also, since moving here, rapidly becoming my favourite beverage. I didn’t think anything could top coffee as my morning drink of choice, but I think matcha just might. Needless to say, discovering that it’s apparently good for my brain is certainly another point in its favour…
★ Yes, Kyoto has a tea laboratory. This makes me happy.
♣︎ The somewhat poetic literal translation of the name is “jade dew”. This is widely regarded as the finest tea in Japan. And very tasty it is too!
♥︎ I errr… should probably confess to the fact that I do drink an awful lot of tea…