Slim-Fast recently issued a voluntary recall of their Ready-to-Drink products in cans due to a possibility of bacterial contamination.  You can read the details of the recall here:

http://www.slim-fast.com/recall.aspx

It is advisable to throw any Slim-Fast cans away and you can call the company at 1-800-896-9479 for a full refund.  They are open M - F, 8:30 - 6 PM ET.  Generally speaking, if you want to lose weight, eat more fruits and vegetables.  For instance eating an orange or apple instead of orange and apple juice goes a long way.