I have been (somewhat) blessed in the weight department, only insofar as I have never had the need to lose weight. I have not been able to successfully gain weight and keep it on, which some consider a "champagne problem," but can actually be pretty difficult to deal with on its own. Still, I do sympathize with those who are looking to lose a few pounds.
Make a plan, and plans start with ample research. Look into reviews and find one that fits your needs, then be sure to study the possible side-effects and contact your health provider with any questions you may have.