Is local food better for the climate?

Usually what you eat matters far more than where it comes from. Transport is a minor source of emissions for most foods, the UN climate panel IPCC writes1. For beef, packaging, transport and retail together cause just 1 to 9 percent of emissions, according to the largest comparison of food footprints2.

The differences between foods, on the other hand, are large. In CONCITO's Danish climate database, footprints range from 0.25 kg CO2e per kg of onions and 0.90 kg per kg of wax beans to 185.76 kg per kg of beef tenderloin3. According to a review from Aarhus University, the average footprint of beef from the slaughterhouse is 50.2 kg CO2e per kg4.

Transport can matter for a few foods. For bananas, which have low emissions and travel far, transport can be over 40 percent, but of a small total footprint of 0.7 kg CO2e per kg1. Planes and trucks use roughly ten times as much energy per tonne and kilometre as ships and trains1, so air-freighted food is an exception. Local isn't always best either: vegetables from open fields can have much lower emissions than local vegetables from heated greenhouses, and imported food can have a smaller footprint than local food5.

So it is the choice of food, not how far it travels, that decides most of its climate footprint.