I've read a lot of reviews with mixed results. In some, users say it didn't have any effect on them at all. But I've notice they've failed to mention whether or not they've been exercising while taking it. I know the drug is supposed to be a metabolism booster. Which is why I'm hoping if I continue my daily routine of running/ using Arc Trainer for two hours or until I've burned 2000 calories while taking the product I might see faster results.