New scientific developments and research into the health effects of green tea have advanced significantly. Studies have shown that green tea is made of several main components that contribute to its character: catechins (texture), caffeine (bitterness), and theanine (flavor), as well as various vitamins and minerals. Present in large quantities of green tea, catechins (including EGCG) are a type of polyphenol that is also a component of red wine. Catechins also give green tea its unique texture, and as a potent antioxidant, hinders dangerous free radicals in the body.
Caffeine gives green tea its bitter taste while increasing alertness and relieving fatigue. Theanine, an amino acid, gives green tea its taste and acts as a mild relaxant. Theanine helps to relieve the jittery effect that caffeine can sometimes produce in sensitive individuals.
This makes it a great alternative to coffee which not only has higher levels of caffeine but does not contain theanine to regulate the unpleasant physical side effects. These are the main research properties included in green tea. Green tea contains a well-balanced mix of these ingredients, not to mention it's ability to help with weight control.