Vegans might win, but to follow on Chris' comments you can still score by choosing food with less CO2 on a meal-by-meal basis, kind of like how we usually view actions like changing a light bulb or deciding whether to drive vs. walk.  Bernard Brown
Director, PB&J Campaign

No mention of Corn…

But cheese is usually eaten sparingly. Not many people sit down and eat a “cheese cutlet”.  An ovo-lacto vegetarian will probably consume the same amount of cheese and eggs in a week as a typical meat eater would eat in meat for one meal. (That's a tongue twister.) The real problem with most meat eaters isn't that they eat meat at all, it's the immense quantities of meat they consume.