I saw a link to this video on an O'Reilly web blog - good stuff, but how many people are willing to watch a 30 minute video, even for important issues?
A summary of Michael Pollan's points that resonated with my own beliefs (with my opinions added): The real costs of eating unhealthy food that also stresses our environment in production are hidden by huge government subsidies and the politics of agriculture corporations bribing and influencing the US Congress, and more recently the executive branch. In a weak economy and energy crisis the best "green industry" to promote is small farms that grow food close to where people live and run by farmers who are very skilled in running farms in an ecologically intelligent way. Higher costs of locally grown healthy food that leads to a sustainable society look more reasonable when potentially lower health and energy costs are factored in. This could be highly beneficial to farmers but would reduce profits of the giant agriculture corporations.
In the video, John Battelle and Michael Pollan talked about ways that transparency in our food industry would self-correct consumer food choices. If supermarkets were required by law to post pictures or videos of industrial meat factories then many consumers would naturally switch to healthier food alternatives, even with small extra expenses. If consumers understood the health risks of highly government subsidized foods like low quality factory meat, soybean oils, and highly processed corn-based products then free market forces would shift production to more "society friendly" food products.
You can help yourself and society by trying to buy locally grown food.