If she lost 12 pounds in 17 days, then she lost a lot of water weight and everything in her digestive tract

You have to burn 3500 cal more than you consume just to lose one pound of fat.
The diet is a very low carb diet with the addition of very expensive shakes. I checked their supplements and don't see anything that has actually been proven to assist in fat loss.
In my personal opinion, there are better ways to lose weight
