What health benefits are associated with drinking green tea?

None: The studies have failed to show any benefit from drinking green tea.

As a 0-calorie drink: Green tea, without sugar, cream, or other calories in it, helps decrease the total amount of calories one eats or drinks in a day. This means the green tea substitutes for other food/drink that contains calories. If one continues to eat /drink other foods and drinks that contain calories, and is not using the green tea to substitute for some calories, then the tea will not help with fat reduction.