Calculate your carbon emissions for food using NZ data

Increased uptake of plant-based diets in New Zealand could substantially reduce greenhouse gas emissions while greatly improving population health and saving the healthcare system billions of dollars in the coming decades, according to a new University of Otago study.

Lead researcher and Otago medical student Jono Drew explains the global food system is driving both the climate crisis and the growing burden of common chronic diseases like cardiovascular disease, diabetes, and cancer.

Jono created a database of 341 food items. He has calculated CO2e value (expressed in kg) for each food item. This includes the emissions generated at every stage of the production and distribution of the foods in New Zealand. The image below summarises the findings by major food categories.

Inge Bremer from Carbon Neutral Trust has worked through Jono’s data and condensed it into the 97 food types that we are most likely to consume in an average week. This has been presented in a Google Sheets spreadsheet that you can either download or use online. When I used it, I entered my portion sizes for the most common range of food and beverages that I would consume over an average week. This generated a weekly CO2e value in kilograms and by multiplying that up by 52 (weeks) gave me an annual emissions figure. At just over 1,700kg, this was similar to the figure that the Trust's carbon calculator generated when I calculated my carbon footprint.

Even if you don’t complete the calculations, the spreadsheet highlights which foods generate the highest emissions. Even better, these figures are New Zealand specific. Inge discovered that emissions for NZ grown and produced food are significantly lower than for those grown in the USA. Furthermore, you can also see the difference in emissions between food that you produce yourself compared to purchasing it.

Having used the Trusts calculator, I become aware of the impact that my overall consumption habits are having on carbon emissions. Food is now my single biggest contributor so the spreadsheet will be a great guide for helping me to work on reducing my footprint even further.

A screenshot of the spreadsheet - click to visit