People who are thinking about their carbon footprint have probably heard of food miles. The phrase brings to mind an image of bananas or avocados shipped halfway across the world, emitting huge amounts of carbon dioxide into the atmosphere.
In reality, while food miles do add to the climate footprint of each food, they are far from being a full representation of its climate impact, and nor do they reveal the impact of that food on pollution, deforestation, or on-farm emissions. Let’s dive into what food miles do and don’t capture.
WHAT ARE FOOD MILES?
Food miles measure the distance that food travels from farm to plate. This can include transport by plane, ship, train, or cargo truck as food gets to a supermarket, and also the travel of the consumer to the supermarket and back to their house.
WHY ARE FOOD MILES A PROBLEM?
CARBON EMISSIONS FROM TRANSPORT
Food miles are logistically difficult to measure, often involving multiple forms of emissions, and the food miles of particular products can vary widely from country to country, food type to food type, and supermarket to supermarket.
The scientific community is not in consensus about the percentage of food’s total carbon footprint made up of food miles, but it is clear that this figure is relatively low. Our World In Data shows the percentage of emissions transportation contributes to the climate impact of each food, and you can see that transportation is a minor contributor. Their advice is to worry less about eating local, and to focus on the foods that create fewer emissions across the entire supply chain, and those are plant-based foods instead of meat, dairy, and eggs.
However, it certainly does no harm to choose locally grown plant-based products wherever possible. In the UK, transporting a tonne of food by air emits 1.26kg of carbon dioxide per kilometre, while road transport emits 200g. Rail and water transport involve ever fewer emissions, 40g and 30g per kilometre respectively. So buying local produce is a good thing, but eating plant-based is always better.
OTHER PROBLEMS WITH FOOD MILES
While carbon emissions from transport are the most obvious issue relating to food miles, there are other reasons to care about the distance that food travels to the consumer.
SUPPORTING BIG CORPORATIONS
Most products that log significant food miles come from large corporations. In the United States, for example, about 80 per cent of commonly bought food products are made by just a few companies. Reducing consumption of foods imported from distant countries and replacing them with locally grown foods can be beneficial to local communities and smaller businesses, especially if you are buying from trusted farmers’ markets or food fairs where you can directly support local farmers and cut out the middleman.
Transporting food across longer distances often requires more packaging, which tends to be made of plastic and other ecologically harmful materials. These materials can be damaging to the planet and may require further energy and money to dispose of carefully.
WHY SHOULD WE REDUCE FOOD MILES?
While food miles only comprise a small portion of food’s overall carbon footprint, it is still important to reduce these emissions. It is impossible to reach the climate goals of the Paris Agreement (keeping temperature rises over pre-industrial levels to under 1.5C) without working on making our agricultural systems more sustainable. While switching to plant-based is the “single biggest way” we can do to help the planet, reducing food miles will also play a part in that.
HOW CAN WE REDUCE FOOD MILES?
The easiest way to reduce our own food miles is to calculate the food miles of various products and then remove the ones with the highest mileage. One online calculator can be found here. However, calculating every food mile can be daunting, so we could just look on the pack for the country of origin of fresh produce and not buy any that have travelled a long way. Then, if you are able to determine the mode of transport, focus on eliminating products that flew to your area as opposed to products that were shipped by trains, trucks, or boats. Food miles from planes are far more harmful than food miles from these other forms of transport. Thankfully, air freight only accounts for less than one per cent of all food miles, so this is not as prevalent an issue as many believe.
We can also buy more seasonal food, as food grown out of season often, but not always, requires a longer transport time. If you need help figuring out which foods are in season, read this helpful guide. And one lovely side effect of eating seasonally is really looking forward to the different times of the year when different produce becomes available. There is a lot to be said for delayed gratification!
We can also support local businesses like veg box schemes and farmers’ markets. These will almost always sell local produce which is often organic and has reduced packaging too.
Another solution can be growing some food ourselves, although this depends on the space you have available. Cultivating some choice veggies or herbs can do a little bit to reduce your carbon footprint (plus it’s fun!).
DO FOOD MILES REALLY MATTER?
While it is intuitive that food miles contribute to greenhouse gas emissions and other forms of environmental pollution, they are not the most important way that our food impacts on the environment. In fact, the type of food is far more important than where the food comes from.
Animal products, including red and white meat, farmed fish, cheese, and milk cause far greater emissions than vegetables and other plant-based products, including plant-based meat substitutes.
For example, beef produces about 60 kg of carbon dioxide per kilogram of meat, while the same amount of green peas only produces about 900g. Even processed plant-based replacement products are far more sustainable than their animal-based counterparts.
In short, an avocado trucked from another country will be a far more sustainable product than local meat, but a locally grown vegetable will be best of all.
Because of this overwhelming evidence, many climate scientists now advocate for consumers to begin reducing their meat and dairy consumption before reducing food miles.
DISADVANTAGES OF FOOD MILES
As mentioned above, food miles do not accurately capture the emissions from the production of food, which is far more important than transport. But food miles also cannot analyse other environmental problems with food — like land use, water pollution, pesticides, energy use on farms, and other emissions from production.
Of these factors, land use may be most critical. Animal agriculture takes up a disproportionate amount of agricultural land because so much land is required to grow feed for farmed animals. According to one estimate, if the world switched its animal-based agricultural systems to plant-based, we’d be able to free up three billion hectares for other purposes or simply to return to nature. That’s an area the size of North America and Brazil combined. If this land were to be rewilded, the vegetation would be able to sequester a further estimated 332 to 547 billion metric tonnes of carbon dioxide.
Not only do factory farms and animal agriculture take up a lot of land, but it pollutes waterways and harms local biodiversity. It also raises the risk of pandemics through deforestation and increased interaction between non-native species, while factory farms provide ideal breeding grounds for dangerous pathogens. While food miles are certainly something to consider, any environmental conversation should include all of these issues as well.
The upshot is that choosing that avocado flown in from Mexico might still be a more environmentally friendly choice than eating locally raised beef from your high street butcher.
Eating local does have benefits, like supporting your neighbourhood economy, elevating small farmers, and small reductions in carbon emissions. However, “eating local” can, at best, be considered only a small tool for helping the environment, not a true solution. Changing what we eat, primarily from animal-based to plant-based, is a far more effective solution in nearly every single way.