Not a 'documentary', but the Food Revolution Summit hosted by John and Ocean Robbins, is an annual audio event of multiple speakers in areas of nutrition, environmental and political concerns. I listen every year, and you can of course buy the tapes. The programs are rerun for a time. You can even listen directly on your phone to not use data.
Find out what the world’s top doctors eat for disease prevention, energy, mental health, and longevity.
www.foodrevolutionsummit.org
John Robbins book Food Revolution, along with Diet for a New America are worth owning!