Hi, I have no medical proof that any work, and think they're all some extremely wealthy gits idea of conning insecure people into spending lots of money on false hope. However, saying this, my Mum recently bought some tablets from the local chinese Health store to boost her metabolism - she has thyroid probs and has a nightmare losing weight.
Anyway, They were quite expensive - �50 for a months supply - but, after only 2 weeks, she has said she has already noticed a difference. Not to be graphic, but she is going to the toilet a lot more, and her clothes are already looser on her, and she really does believe they are working. She doesnt want to weigh now, but is going to wait until the month is up to see how much she's lost.
Anyway, my advice is maybe to go to a Dr Health store, or somewhere similar, and have a chat with the guys there. Maybe you just need something to kick start your metabolism into 'weight loss' mode.
Good luck xx