Acai suppliment question?

i was just wondering if this acai berry stuff really works. im a teenager and im looking to lose about 10-15 lbs. would this product be worth buying and would it help me with that? and also i went to walmart to buy it and all they have is something call ACAI it doesnt say ACAI "BERRY" on it but it still says its a dietary suppliment so is it the same thing as acai berry?