Instruct: Classify an Amazon review into positive or negative sentiment.
Query: Science quacks

I too read and practiced Fit for Life several years ago, and found myself losing much weight quickly-too quickly. I now know I lost lean body mass because I was not assimilating enough protein and fat to rebuild cells so the building materials were being taken from existing muscle. This book, although seductive in its mantra of returning to a totally natural state, is not based upon any science at all. None of the theories propogated by the Diamonds concerning food combining have any CLINICAL basis in fact, and a high-school level understanding of human physioliogy and cellular transport blows holes in their reasoning. This is a diet which consumes all of your time and energy, and leaves you either fat and bloated from consuming food willy-nilly out of frustration, or skeletal and weak from insufficient amounts of protein.