Does eating local cut your food’s carbon footprint?

The objection

“I buy local. Cutting food miles does more for the planet than going vegan, and beef from the farm down the road has to beat lentils or tofu shipped across an ocean.”

The answer

Wanting to back local farmers and cut fuel use is a decent impulse, and there is one case, food flown in by air, where distance really does matter. For almost everything else the numbers run the other way, because what a food is decides its footprint far more than how far it travelled.

How much of food’s carbon footprint comes from transport?

Transport is about 6% of food’s greenhouse gas emissions worldwide [2], in Poore and Nemecek’s data from about 38,700 farms in 119 countries (2018) [1]. Farming and the land it takes, including methane from cattle, fertiliser and the clearing of forests and grassland, make up 82%, and processing, packaging and retail most of the rest [2]. For most individual foods, land use and farm-stage emissions account for more than 80% of the footprint and transport for less than 10%; for beef from beef herds, transport is 0.5% [3]. A US study (2008) found the same at household level: production made up 83% of the average household’s food footprint, transport of every kind 11%, and the final trip from producer to shop only 4% [4].

Is local beef better than imported plant foods?

No: local beef has a far bigger footprint than plant foods shipped from the other side of the world. A kilogram of beef from a beef herd emits about 60kg of CO2-equivalent, and a kilogram of peas about 1kg [3]. Our World in Data worked through the extreme case: shipping beef about 9,000km by sea from Central America to the UK adds roughly 0.2kg of CO2-equivalent per kilogram, about 0.35% of its footprint, so beef from the farm next door, carried home on foot, still comes to about 59.8kg (2020) [3]. The US study reached the same verdict from the other direction: moving less than one day a week’s worth of calories from red meat and dairy to chicken, fish, eggs or plant foods cut more emissions than buying all food locally (2008) [4]. Local can even be worse. One study (2009) estimated that Spanish lettuce imported to the UK in winter had three to eight times lower emissions than lettuce grown in the UK at that time of year [3].

Which imported foods should you avoid?

Air-freighted food is the real exception, and it tends to be highly perishable produce such as asparagus, green beans and berries [5]. Flying food emits about 50 times as much per tonne-kilometre as shipping it, but only 0.16% of global food miles are flown, and nearly 60% go by sea [5]. Our World in Data’s example is asparagus flown about 10,000km from Lima to London, which adds about 11kg of CO2-equivalent per kilogram and takes it to almost 12kg, more than a kilogram of chicken or pork (2020) [5]. Avoiding food with a very short shelf life that has come a long way is worth doing; after that, the bigger change is what goes on the plate.