It is often said that drinking tea helps us to stay alert and focused for extended periods of time. But a scientific study has revealed that drinking one to four cups of tea throughout the day focuses attention, improves alertness, accuracy and enhances the ability to ignore distractions – which in turn helps to boost our general performance.
According to the study, the main reason for this is both green tea and black tea contain Caffeine and L’theanine which are known to increase alertness and focus. The unique combination of L’theanine and Caffeine is responsible for the alertness and focus that we feel after drinking a cup of tea. Alertness can increase over up to five hours, which helps to prolong the ability to focus. Caffeine stimulates the mind and body, while L’theanine stimulates ‘alpha’ brain activity.
This makes tea a great beverage if you are looking to improve energy and focus with small amount of caffeine content compared to coffee.
Psychological effects of dietary components of tea: caffeine and L-theanine from https://www.ncbi.nlm.nih.gov/pubmed/18254874