Green tea is a very healthy drink, as it contains high amounts of antioxidants that reduce the risk of cancer and disease. It has also been shown to reduce cholesterol, improve blood flow and prevent cell damage.
Catechins are the plant compounds primarily responsible for green tea's benefits. Because green tea is not highly processed or roasted after it is harvested, it retains a high amount of the catechins naturally found in its leaves. In addition, green tea is rich in theanine, an amino acid that is said to aid relaxation. Expensive teas are generally more effective than the cheaper, canned versions.