Recently, we published an article on caffeine and how it could help with dementia. A lot people responded to this article with comments — including one question about whether caffeinated tea could be neuroprotective in the same way that coffee is. The short answer to that is: yes. Japanese researchers recently studied the brain-protecting effects of a special compound in tea called “theanine.”
Theanine is found in tea leaves (“Camellia sinensis”). It has a similar chemical structure to glutamate, which is a neurotransmitter related to memory. The Japanese research team found that once theanine passes through the blood-brain barrier, it exerts a brain-protective effect. They also found that the tea compound exerts a preventive effect on neuronal cell death after transient cerebral ischemia. “Transient cerebral ischemia” is a medical phrase used to describe a mini-stroke. The fewer brain cells that die during
one of these mini-strokes, the better the chances of recovering without any brain damage — which is exactly what theanine seems to help with.
For their study, the research team conducted an investigation of elderly persons with normal or slight cognitive dysfunction. All the volunteers ingested powdered green tea containing a high theanine concentration. They showed significantly lower decline in
cognitive function compared with that of a placebo group. This result suggested that theanine might even be able to improve cognitive dysfunction in elderly persons.
Other studies have suggested that it’s the combination of theanine and caffeine that could help improve cognitive performance. A dose of theanine and caffeine prior to performing a demanding cognitive task may significantly improve accuracy and alertness. These two ingredients together could help increase your ability to focus.
The next time you drink a cup of green tea, you could very well be protecting yourself from the kind of cognitive brain decline that leads to diseases such as Alzheimer’s. At the very least, this “brain food” will give you a big dose of health-boosting antioxidants.