Climate diet: What to eat to ensure we all live longer
If we are serious about tackling climate change, most of us need to eat fewer animal products. But there are other benefits, too. By Andrea Graves.
It's been a harsh summer in the northern hemisphere. In legendarily green, rainy England, roads melted in July, and the London Fire Brigade had its busiest day since World War II. People literally died of the heat – during the last two weeks of July, there were about 16 per cent more deaths in the UK than normal for that time. Elsewhere, there has been immense climate-related suffering: horrific heatwaves in India and China, and devastating floods in Pakistan, China and Uganda.
Almost everyone has got the message by now: combating climate change is not something we can put off until the future – it is already starting to bite. When it comes to putting some teeth behind your actions, however, what kind of diet might help? What is the most climate-friendly diet, and is the trade-off malnourishment?
According to the latest report by the Intergovernmental Panel on Climate Change (IPCC), a plant-based diet is the biggest behavioural shift a person can make to reduce their individual greenhouse-gas emissions. Food choice falls into the "shift" rather than "avoid" category, says the IPCC, because the global food system is responsible for about a quarter of human emissions.
But what exactly does "plant-based" mean? Merriam-Webster hasn't yet added the term to its dictionary, stating that the definition is still unclear. To some people, it means cutting out all animal products, but to many, it encompasses low-meat diets. It can mean vegan, vegetarian or flexitarian.
Whatever rules you follow, there appears to be a growing number of such eaters in Aotearoa: according to an annual survey of more than 1500 Kiwis commissioned by Rabobank, vegetarians have increased from 7 per cent to 9 per cent of respondents over the past year, while those declaring themselves vegans are up from 2 per cent to 5 per cent. Nearly a third of those surveyed want to eat less meat, whereas 7 per cent plan to eat more.
Milking it
Australasians are the world’s biggest red-meat and milk consumers, outpacing even high-income North Americans. People in South Asian countries eat, on average, about a 20th of our typical red-meat intake.
Red meat sits at the pinnacle of greenhouse-gas producing foods. Beef consistently leads the pack, followed by lamb, processed meats, pork and cheese. Milk in its unprocessed form falls far lower on the scale. But products’ emissions depend on how they are produced; New Zealand beef, lamb and milk lie at the lower end of the spectrum, but still well above plant proteins.
Local research shows that cutting out meat still significantly lowers diet-related emissions. A University of Otago study found that compared with a standard New Zealand diet, vegetarianism cut emissions by 30 per cent and veganism by 33 per cent. Another study showed that meatless but dairy-rich fare cut dietary emissions by nearly a quarter. That study's authors, who were mostly from the Ministry for Primary Industries and Massey University's Riddet Institute, emphasised that a century from now, when the eater will have died, the methane emissions associated with meat will have largely finished exerting their powerful warming effect and broken down. However, if younger generations keep eating meat, they're likely to keep methane levels elevated.
One of the study's authors, Carlos Gonzalez-Fischer, is now at Cornell University in New York, but was previously at the New Zealand Agricultural Greenhouse Gas Research Centre. Gonzalez-Fischer, whose speciality is food systems with an emphasis on livestock and climate change, says the important message is that all studies show that changing your diet to reduce your meat intake can significantly reduce dietary emissions.