Other herbs are considered thermogenic, better known as "fat burners", due to the natural presence of caffeine.
Because of this minimal processing, the leaves retain many of the plant's properties, including its thermogenic action, thus increasing metabolic rate.
Some people think that grapefruit is a thermogenic food, or one that burns more calories to eat and digest than it contains.
A December 1999 American Journal of Clinical Nutrition Study concluded that "Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se."
Along with reported thermogenic (fat burning) properties, green tea may also help dieters particularly prone to stress eating.