I would talk to a doctor before starting any weight loss supliments. really i have tried half the gimmiks out there before i got smart enough to look to science to see if they are any good. found out lots were very dangerous.
here is two that have some scientific basis ...capsicum can help speed your metabolism....but you dont need a suppliment just eat some peppers!
green tea....has been shown to help.......but dont spend a million bucks on it spend a buck and a half at the grocery store.