My opinion is not to rely on drugs (call them supplements if you want) to lose weight. Most of the effective ones are nothing more than stimulants, which potentially pose their own set of problems. Ever hear of Fen-Phen? VERY effective. Also killed some people.
If you want to kick your metabolism, add
weight training to your cardio. Research shows that cardio burns calories and fat while youre doing it and then for a short time after, but weight training carries the stimulation of your metabolism for a number of hours.
Make sure you're eating about 500 calories less than your required intake. It's hard to lose weight without a
calorie deficit, or if that deficit is too big.