Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A long, boring self (and product) promotion!

I expected to find some product placement (and there was), but had no idea that most of the book would be Dr. Perricone bragging about how much smarter he is than all other scientists and doctors and taking credit for other peoples' work! There were also a lot of technical mistakes that I found (as a medical student) that make me wonder if he even understands the science that he claims to have discovered. To top it all off, I received some of his products as a gift and they were terrible. If you are interested in MD-formulated products, try MD skincare or Murad, both actually work (and, though I haven't read their books, they can't be worse).