Many people advocate buying local as a way to reduce the greenhouse gases causing climate change. Buying from local or regional farmers who grow and raise your food, so that it doesn’t have to be shipped a long distance, saves the CO2 used in transportation, but in fact doing so only saves about 10 percent of the total greenhouse gases that are generated in growing and processing most of the food we eat, according to an expert who has analyzed where most of the climate impact of our food comes from.

It’s the kind of food that ends up on the truck that determines the carbon footprint, explains Sandra Noonan, the Chief Sustainability Officer of Just Salad, a restaurant chain, and it is one more reason to switch to a plant-based diet. Supporting local farmers is always a good idea, but it doesn’t have a huge impact on our carbon footprint, since most of the greenhouse gases generated in producing food happen earlier than the final step of trucking it to your local market or store.

More important from a sustainability point of view than how far it has travelled, is what the food actually is. The big advantage here goes to plant foods. One new report published by Stanford University says that by shifting away from meat and dairy, we could lower our climate impact by 68 percent.

Buying locally sourced beef is almost never going to be a better option than shifting to a plate of all vegetables, legumes, fruit, and whole grains. Locally raised beef is still worse for the environment than buying broccoli or lentils that was grown further away and had to be shipped across the country to your store, although of course, locally grown plant foods are best of all.

Now, companies like Just Salad and others are adding labels to ingredients and the food they serve up, that shows the environmental impact of our dish, how much CO2 was burned, and methane was released in the growing, harvesting, processing, and transporting of our food from soil to bowl and beyond. It’s here that consumers will see the big difference between plant foods and animal foods. Let’s hope these new labels will help encourage more people to switch to plant-based options.