According to various studies on cardiovascular health, tea, in general, is associated with reduced risk of cardiovascular diseases, specifically lowering the risk of myocardial infarction, stroke and ischemic heart disease.
Consumption of two to three cups of black or green tea per day improves blood vessel function.
Tea consumption can help in weight management program, as in a number of Asian studies that found a reduction of visceral fat after consumption of high catechin green tea for 12 weeks. It was also shown that high catechin green tea increases fat oxidation.
L-theanine, on the other hand, is an amino acid naturally exclusive from tea that is responsible for the production of alpha waves in the brain which has a calming effect on the body and gives the balance of deep relaxation and mental alertness, according to Dr. Edgardo Tolentino of the Makati Medical Center.
A typical 200mL serving of black tea contains 4.5 — 22.5mg of L-theanine.
Research showed that a day long of tea drinking provides the same alertness as coffee drinking, but tea less likely disrupts sleep and improves mental alertness on attention tests.
Moreover, coffee compared to tea produces beta waves which put the body in an agitated state, and caffeine which increases attention and vigilance, works against adenosine which inhibits neural activity.#