Do Japanese know about fat loss from green tea?

Green tea and matcha, especially at high doses, contain significant amounts of caffeine and catechins, namely EGCG. Together, they have a synergistic effect on fat cells by causing them to release more fatty acids to be used as energy. This has been studied to great effect in reducing bodyfat, particularly when combined with exercise. In America, matcha has become more popular and companies like Starbucks offer matcha drinks. This concept of fat loss is still very obscure even in fitness circles, with most people having a vague idea that green tea is "good for you" at best. Is this concept of green tea supporting fat loss known by more Japanese? Is it used in advertising?