New Study: Changing Diets Could Play a Key Role in Reducing Greenhouse Gases

New research confirms what many climate scientists have stressed about the link between plant-based diets and climate mitigation.

According to a new study published in Nature Climate Change, if people change their food choices towards more plant-based diets, greenhouse gas emissions that warm the planet could fall by 17%.

In fact, researchers estimate that if the 56.9% of the global population currently over-consuming were to adopt the planetary health diet proposed by the EAT-Lancet Commission, it could reduce global dietary emissions by 32.4%. The international group of researchers said that switching to the planetary health diet could offset the 15.4% increase in global dietary emissions expected if the 43.1% of the global population currently under-consuming moves toward healthier diets.

The study looks at the uneven distribution of dietary emissions, including land-use and beyond-farm emissions, from 140 food products across 139 countries, covering 95% of the global population. It highlights the extent of dietary emissions inequality within countries based on detailed spending data.

To meet the demand changes, especially if the world moves toward a plant-based diet, “the composition of global food production would need to change considerably to adapt to the substantial changes in demand if the meat-to-plant pathway is to be followed.”

Overall, the study reveals that affluent countries tend to have high-emission diets with relatively low levels of inequality, while poorer countries often have lower-emission diets but face higher levels of inequality. Notably, within individual countries consumer groups generate more dietary emissions due to greater red meat and dairy consumption.

"Compared to plant-based products, animal-based products show greater potential for reducing emissions,” corresponding author, Dr Yuli Shan, from the University of Birmingham, said in a press release. "We should look to reduce over-consumption of emission-intensive products in affluent countries, such as beef in Australia and the US especially for wealthy consumer groups who are overconsuming, which would help to achieve significant health and climate benefits."

Consumers can be encouraged to change their diets through incentives like carbon pricing, eco-labeling, and increasing access to less emission-intensive products, such as vegetarian foods. The researchers also stress the importance of a thoughtfully designed food environment that can reshape dietary patterns. Combined with the parallel development of urban planning and infrastructure, a well-designed food environment can potentially “reduce the time and financial barriers stopping people from adopting healthier diets.”

Lower-cost, calorie-dense foods have fewer nutritional benefits, the researchers said, pointing out that poorer populations often consume these foods due to high costs and low affordability—the “highest barrier” preventing these populations from developing healthier diets. Moreover, the researchers recommend that policymakers must focus on making food more affordable and accessible to groups with lower expenditures.