Forks Over Knives

The documentary's claim is direct: that illnesses such as heart disease, type 2 diabetes and some cancers are largely a matter of diet and can be pushed back by cutting out animal products. The film builds this on the work of two researchers and at the same time follows several patients; the participants change how they eat and their blood values are measured at intervals. The director puts his own tests in the film as well. Lee Fulkerson directs. The documentary dates from 2011. At its centre are T. Colin Campbell, who works in nutritional biochemistry, and the heart surgeon Caldwell Esselstyn; each describes his own research programme. Campbell's part in a large nutrition study conducted in China is given in detail and is the documentary's main support. The method is advocacy rather than observation; the narrative gives no room to the opposing view and presents the argument as closed. The film had an effect on the spread of plant based eating in America, and books and cookery programmes of the same name followed. Scientific criticism concentrated on the film drawing causation from observational studies; that objection is not addressed in it. Its most concrete side is number; the patients' measurements are shown on screen. Who it is for: people who watch documentary on nutrition and health. Who it is not for: it is one sided, the claims are put absolutely, and the film is no substitute for medical advice.