Is local grown food more environment friendly?

Question

Are locally produced food ingredients always more environment friendly than the same non-local ingredients?

Answer 1

Currently, there are no strict definitions of ‘local food’, but the most common definition relates to food that has been produced in the locality of the consumer. The actual size of the locality remains undefined.

But transportation represents only 11% of life-cycle GHG emissions of the average household’s food consumption in the United States, while the production phase contribute to 83%. In most cases where local food does reduce greenhouse gas (GHG) emissions, this arises due to differences in the emissions intensity of production, not reductions in transport related emissions.

Factors that could impact how environment friendly a local food may be:

• Agriculture technologies used. This study found Swedish production of broccoli to be heavily dependent on the use of diesel whereas the South and Central America’s agricultural technologies less mechanised and less dependent on primary fossil fuel consumption.
• Emissions associated with storage of local food. For 3 of the 4 products studied, emissions were lower when produced in New Zealand and transported by sea to the UK than when produced in the UK and sold domestically.
• Use of heated greenhouses for fruit and vegetable production. Greenhouse tomatoes use 10–18 times more energy than open grown crops.
• Nutritional quality of local food. The evidence suggests that the nutritional quality of the fruit and vegetables is probably highest straight after harvest and then declines with time. Some vegetables that are sold locally may have been stored for days or weeks, especially when stored to be consumed out of season.
• It may require more inputs to grow the same quantity of food locally, including more land and more chemicals - all of which come at a cost of carbon emissions.

If you happen to live in an area which is endowed with natural resources to produce the foods you consume, such as temperature, rainfall, sunlight and soil quality, as well as efficient production technologies, then it may be environment friendly for you to rely on local food.

If not, then changing 1 day per week’s consumption of red meat and dairy to other protein sources could have the same climate impact as buying all household food from local providers. Given the difficulty in sourcing all food locally, changing the diet for one day per week may be more feasible.

For households which already exhibit low-GHG eating habits, reducing the freight emissions of food may further reduce the environmental impact of their diet. For instance, imports of Kenyan and Guatemalan beans entail a global warming impact many times greater than UK beans, once air freight is factored into the analysis. To find out which foods are air freighted, see “What Food Travels by Air to Get to Us?” (OneSharedEarth, June 2020).

 

Bibliography

Edwards-Jones G, “Does Eating Local Food Reduce the Environmental Impact of Food Production and Enhance Consumer Health?” (2010) 69 Proceedings of the Nutrition Society 582

Misak Avetisyan, Hertel TW and Sampson G, “Is Local Food More Environmentally Friendly? The GHG Emissions Impacts of Consuming Imported versus Domestically Produced Food” (Semantic Scholar, 2014)

Sexton S, “The Inefficiency of Local Food” (Freakonomics, November 2011)

Weber CL and Matthews HS, “Food-Miles and the Relative Climate Impacts of Food Choices in the United States” (2008) 42 Environmental Science & Technology 3508

“What Food Travels by Air to Get to Us?” (OneSharedEarth, June 2020)

“What Greenhouse Gases Are Emitted by Human Activities?” (OneSharedEarth, January 2020)

Answer 2

There are many environmental benefits to eating local food. Food grown nearby generates fewer food miles in transportation, reducing fuel use and greenhouse gas emissions. Asparagus grown in the UK has a carbon footprint 28 times lower than asparagus transported by air from South America, for example.

Eating seasonal foods also helps to reduce energy use, since the production of non-seasonal foods is more energy-intensive. As a result, eating seasonal foods grown further away may sometimes be a more environmentally friendly choice than eating local produce grown out of season.

According to Emily Honeycutt, eating local contributes to the preservation of green spaces. Small farms kept in business help to reduce the amount of green land lost when it is sold to property developers. Another impact to consider is the need for road systems to transport food. Road construction results in deforestation and disturbs the habitats of wildlife. This impact is of lesser significance, however, considering that the creation of extensive road systems has already gone underway in most countries.

Whilst eating local food does have benefits, a study by Hannah Ritchie and Max Roser found that eating local was really of little significance in determining the environmental impact of food consumption in comparison to considering what kinds of foods are being eaten. Ritchie and Roser state that:

‘Eating locally would only have a significant impact if transport was responsible for a large share of food’s final carbon footprint. For most foods, this is not the case.’

If you are interested in reading more about which kinds of food are more environmentally friendly, see our OneSharedEarth question on plant-based diets.

Bibliography

Honeycutt, E., 'Why Buy Local Food? It's Healthier for You and Better for the Environment', Food Revolution Network (21 December 2017), accessed at: https://foodrevolution.org/blog/why-buy-local-food/

Ritchie, H. and Roser, M., 'Environmental impacts of food production', Our World in Data (January 2020), accessed at: https://ourworldindata.org/environmental-impacts-of-food

Terry, A., 'Benefits of Buying Local, Seasonal and Sustainable Food', One Home (19 April 2018), accessed at: https://onehome.org.uk/lifestyle/21-food-and-drink/27-nine-benefits-of-buying-local-seasonal-and-sustainable-food

University of Toronto, 'Local Food: Environmental Impact', Food Services (2018), accessed at: https://ueat.utoronto.ca/local-food-environmental-impact/