There are many choices for you in the tea aisle. I like to ask people, “How many different tea plants do you think exist?” Most people give me a pretty big number. But all tea comes from the camellia sinensis plant.
Any drinks that don’t come from that bushy plant are a tisane or herbal “tea” such as chamomile, mint, rooibos and others. It’s not tea. But let’s not be too snobby about it. Tisanes have their own value.
I drink coffee most mornings and switch over to lower caffeine teas after midday, and then to herbals in the evening.
White, Green, Oolong, Yellow, Black and Pu-erh teas all come from the varieties and cultivars of the camellia sinensis plant. The type and style of tea and its flavor comes from where it is grown (soil, climate) and how it is processed.
Tea has a caffeine in varying amounts depending on that processing. You would think that if a cup of tea could do something to your brain, a cup of strong coffee could do more. But it’s not the caffeine.
Tea contains L-theanine which is an amino acid that promotes mental acuity. That L-theanine along with caffeine creates a sense of “mindful awareness.”
Can we get L-theanine from other sources? It turns out there are very few: a single species of mushroom, and guayusa (a holly species that is sometimes used as a tisane).
Researchers have found that shade-grown teas like the Japanese green tea Gyokuro have higher concentrations of L-theanine because the amino acid is not converted into polyphenols as much as tea leaves that are exposed to full sun.
It is no surprise that monks have been drinking tea for thousands of years. They may not have known that it promoted awareness and alertness, but they probably learned that it helped them get through long periods of meditation.
The caffeine and L-theanine combo is a brain hack that is unique to a drink of tea.
What the L-theanine amino acid does is increase alpha brain wave activity. That promotes relaxation and caffeine is a stimulant. It is an interesting combination. The effects of caffeine are moderated by L-theanine.
Studies have also shown that there are added benefits to tea: increased creativity, increased performance under stress, improved learning and concentration, decreased anxiety, improved ability to multi-task and reduced task-induced fatigue.
That is a lot to get from a cup of tea.