I am a great consumer of green tea. I enjoy its taste and the way I feel after a cup of my favourite tea bag. On average I drink one large cup a day, approximately 500 ml and I have been drinking it for the last 5 years, I have always felt and known that it has many positive effects on health but only recently I have come across an article that nicely presents why it is good to adhere to this habit.
We know that green tea is brewed from the unfermented dried leaves of the plant Camellia sinensis. Green tea consumption has many health benefits, The main healthy compound of green tea with antioxidant effect are catechins. They are important in prevention of disease associated with free radicals and reactive oxygen species, such as cardiovascular diseases, neurodegenerative diseases and cancer. Not to mention the effect on body weight and fat methabolism.
One of epidemiological studies in Taiwan states that habitual tea consumption of 434 ml/day for more than 10 years was linked with a lower percentage of total body fat, smaller waist circumference and decreased waist-to-hip ratio in comparison to non-habitual tea drinkers. There are many more epidemiological studies supporting this outcomes. Why? A typical green tea beverage (250 ml) contains 50-100 mg of cathecins and 30-40 mg of caffeine. Green tea cathehins and caffeine are considered the two active substances responsible for weight loss. There are several biological mechanism of action, including decreased fat absorption, reduced adypocyte lipogenesis and inceased thermogenesis and fat oxidation. Green tea may be a successful and safe strategy for athletes to gradually lose weight with no change in diet.
What about green tea cathecins and exercise-induced oxidative stress? The results of controled interventional studies indicate that regular conspumption of green tea may (at leaast o,6 l/day) may increase total antioxidant potential in plasma and protect against DNA damage in healthy subjects. This is especially important for individuals performing exhaustive exercise.
Howewer, oxidants-antioxidants ratio in our body is also important. We should not supress all the free radicals and other oxidative substances since they contribute to the muscle adaptation to exercise. Therefore, the timing of intake of antioxidative supplements is very important, you should not ingest them before exercise. But ingested after exercise and during any other time they have a prolonged beneficial impact on our performance.