Chicago University researchers to state that going vegan is more effective at combating global warming than switching to a Prius. I'm nervous of this because it might suggest that if you eat tofu you are at liberty to drive a Porsche. Not so. And it should be remembered that some non-meat eaters are feeding their faces with non-sustainable fish (trawler fishing requires about 3.4 litres of fuel oil per kg of fish), cheese from cow's milk (the environmental burden of which is 9-21 times larger than for vegan cheese
