Green tea's EGCG can help with insulin sensitivity, meaning you break down glucose and other sugars more effectively. That does not mean you should start taking green tea pills. Why not just substitute a glass of green tea with your breakfast instead of coffee?
Not to get on my soapbox, but here's why I don;t suggest supplement form. We tend to think of magic pills as just that, something that will fix everything without having to put in any effort. Such as "I'm taking my green tea pills, so I can eat pizza for lunch and dinner." The reverse of that would be "I take green tea extract pills and have lost a lot of weight. It must be the magic pills", not giving credit to the hours you spend on the treadmill.
Dedicated to your weight loss success,
Matt
P.S. I can't post links, but there is a wealth of peer-reviewed research on green tea and insulin sensitivity, which has a great deal to do with losing weight.