This movie advocates a whole foods plant-based diet, somewhat low in fat - not too many nuts and seeds.
This is certainly healthy, as long as you are careful to get enough of the nutrients that may be missing in a plant-based diet, such as B12, calcium, iodine ...
It helps prevent and reverse the metabolic-syndrome type problems that end up killing so many people: obesity, type 2 diabetes, high blood pressure, atherosclerosis. So many people who are fat and sick, in the USA and around the world. It is such a huge tragedy, and it is SO unnecessary.
BUT, this movie tries to sell this diet as a cure for things for which it is not a cure. My autoimmune problems and severe allergies didn't get better after I started eating this way, in 2005 or so. So there's an anti-testimonial, if you like.
There's a very good case to be made for eating this way. For one's health; for the environment; and to prevent animal suffering. Those reasons SEEM like they should be good enough, without making exaggerated claims.
