Dietary changes could help New Zealand reach climate targets

Eating less meat and dairy has the potential to help Aotearoa New Zealand reach its climate goals, say the authors of a new study.

Red and processed meat (35%) and dairy products (19%) were responsible for over half of dietary greenhouse gas emissions associated with New Zealand households' food purchases in 2019, according to an analysis of data from almost 2,000 households and two million purchases.

“Kiwis who want to reduce their carbon footprint can make a significant difference by changing their diets,” says lead author University of Auckland honours student Eli Kliejunas.

New Zealand has committed to a 50 percent reduction in greenhouse gas emissions from 2005 levels by 2030.

Food production is estimated to account for one-quarter to one-third of global greenhouse emissions.

“We have previously done work looking at the healthiness of food purchases and we wanted to look more broadly at the environmental impact of our food purchases in New Zealand,” says Dr Kathryn Bradbury, senior author.

This study used data on greenhouse gas emissions for various foods through the production cycle from farming, to processing, transport, and refrigeration, up until the point of purchase.

Age group of the primary household shopper and household size were significant predictors of per capita dietary emissions.

Households with older primary shoppers had higher per capita dietary emissions, while larger households had lower per capita dietary emissions.

The inverse relationship between household size and per capita dietary emissions could be attributed to increased energy efficiencies and reduced food waste associated with larger households.

This research highlights the importance of dietary choices in mitigating climate change and provides a basis for targeted interventions.

“We know that food products that come from ruminant animals, such as beef, lamb and dairy products, generate a lot of greenhouse gas emissions,” says Kliejunas. “This is because ruminant animals produce methane, which is a particularly potent greenhouse gas over the short-term.

“Global recommendations for red meat intake are generally to eat meat no more than three times a week for health reasons. So, making sure you are not eating more than that will also mean you are reducing your carbon footprint.

“Agriculture accounts for about half of the greenhouse gas emissions we produce in New Zealand, and we export a lot of our meat and dairy products offshore. Policymakers need to work towards reducing both national and global consumption of meat and dairy.”

The study comes in the leadup to COP28 from 30 November to 12 December when the country’s climate target will be in the spotlight. In addition, for the first time the international climate change conference will feature a Health Day on 3 December.