Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Kirsch works!

After trying various diets, I wanted to do something that would have lasting results AND work fast. Kirsch tell the truth about his diet, and keeps his promises on results. Even at 50+, I was able to lose 4lbs a week, and it mostly stayed off after I was done. That's because his maintenance plan isn't difficult. All of his books are great, and using his protein drink was a lifesaver, since I am busy. I highly recommend his eating plan if you want to lose weight fast.