Calculate the environmental footprint of your food

 

When picking which groceries to put in our baskets, a number of considerations are likely to affect our choices – will it tickle our taste buds? How good is it for us? And how much does it cost? But increasingly, consumers are looking for foods that will lower their impact on the environment too.

The food we eat makes up a sizable portion of our individual carbon footprint – depending on where you live and what you dine on, it can account for between 10-30% of your household’s greenhouse gas emissions. The entire food system – which includes the production, packaging, transportation and disposal of everything we eat – accounts for 21-37% of all human-produced greenhouse gas emissions. By 2050, our food could account for almost half of all carbon emissions released by human activity unless more steps are taken to reduce its environmental impact.

But one of the problems we face as consumers is knowing which foods have the least or greatest effect on our planet’s health. Unlike nutritional information that appear on the labels of most foods we buy, easy to read information about sustainability is largely absent.

This is why BBC Future has worked with VerveSearch and researchers at the University of Oxford to produce our Foodprint Calculator. It will allow you to input a selection of staple foods, along with the number of times you consume them in a week up to a maximum of seven, to find out what the environmental impact of your chosen diet might be. Crucially you can also choose a selection of alternative foods to see how changing your diet might alter your carbon emissions. (Read more about the data we used beneath the calculator.)

The figures used in this calculator are based on an average of data from many parts of the world – but the complex global nature of our food chains means the same items produced in different parts of the world will vary wildly in the amount of water they use, the carbon emissions they produce and the fertilisers they require. Your actual foodprint might vary depending on where you live. For example, tomatoes grown in a sunny Spanish climate will use far less energy than in a heated greenhouse in northern Europe, but they might also require more water that has been obtained by desalination.

There are, however, some basic guidelines we as consumers can follow.

According to the recent EAT-Lancet Commission report on healthy, sustainable diets, global consumption of fruits, vegetables, nuts and legumes will have to double. At the same time the amount of red meat and sugar will have to halve. Simply cutting meat and dairy products from their diet can reduce the carbon emissions from an individual’s foodprint by two-thirds.

But some products can have surprisingly high levels of emissions. Rice production, for example, leads to high levels of methane and nitrous oxide – both potent greenhouse gases – being emitted into the atmosphere.

And the food you don’t eat is also important. Throwing away leftovers leads to potent greenhouse gases being released into the atmosphere from landfill. According to researchers in Sweden, for every 3kg of food thrown into the bin, the equivalent of 23kg of carbon dioxide is released as methane gas into the atmosphere. According to one study from Italy, composting food can cut those emissions to just 14% while eating leftovers can cut it even further.

If you want to find out how the food you eat and throw away is impacting the environment, then try our calculator above.