Wealthy nations could slash food-linked emissions by 32% with healthy swaps, finds study

14 Aug 2024 --- Global greenhouse gas emissions linked to food supply chains can drop by 17% if people in affluent countries swap high-emission foods, such as red meat, with plant-based options, according to a group of international researchers from the UK, Netherlands and China.

The study assesses the unequal distribution of dietary emissions based on 140 food products and expenditure data from 139 countries or areas accounting for 95% of the global population.

According to the research, “over-consuming” individuals, who constitute 56.9% of the global population, would save around 32.4% of global dietary emissions if they adopted a planetary health diet proposed by the EAT-Lancet Commission.

The planetary health diet emphasizes a plant-forward diet mostly consisting of whole grains, fruits, vegetables, nuts and legumes, with small proportions of meat and dairy.

Such diet changes would require a restructuring of the current food production order. The global supply (in calorie content) of red meat would need to decrease by 81%, sugars by 72%, tubers by 76% and grains by 50%.

On the other hand, the supply of legumes and nuts would have to rise by 438%, added fats by 62% and vegetables and fruits by 28%.

“The objective of the diet shift scenario is to assess the potential implications of emission mitigation of the food system resulting from changing consumer choices instead of forcing everyone to adopt the same diet,” says Yanxian Li, the first author and a doctoral candidate at the University of Groningen, the Netherlands.

Over-consumption and inequality

Dietary emissions differ across geographies, with wealthy consumer groups contributing more to environmental damage due to their ability to spend more on commodities like red meat and dairy.

The study shows that while such countries have high-emission diets, they show lower levels of socio-economic inequality. In comparison, poorer countries tend to have lower-emission diets but demonstrate higher levels of inequality.

The global supply (in calorie content) of red meat would need to decrease by 81% for a more plant-forward diet shift.Corresponding author Dr. Yuli Shan from the University of Birmingham, UK, says: “Compared to plant-based products, animal-based products show greater potential for reducing emissions.”

“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.”

Researchers also state that switching to a plant-forward diet would balance the 15.4% increase in emissions relating to diet among under-consuming groups, which form 43.1% of the world’s population.

Challenges to healthier diets

Specific nudges can encourage consumer dietary changes, including carbon pricing, eco-labeling and increasing the availability of vegetarian foods that are gentler on the planet. These, in combination with better infrastructure and urban design, can help address bottlenecks affecting the universal adoption of healthier diets, note the experts.

However, the research team maintains that improving nutritional awareness is key in places where foods such as meat and dairy form a major part of the daily diet, such as Mongolia.

Corresponding author, Prof. Klaus Hubacek from the University of Groningen, says: “Low-income countries face greater challenges in reaching healthier diets, with more than 1.5 billion low-income populations worldwide unable to afford the cost of the planetary health diet.”

The study notes that poor people often opt for cheap, calorie-dense foods with less nutritional footprint. As inflation rages on, rising costs and low affordability remain significant challenges to healthier diets.

“Diet shifts need increased food consumption, but Sub-Saharan Africa, as well as South and Southeast Asia, have experienced stagnating agriculture production efficiency for decades and cannot produce nor afford to import the required food.”

He adds that crop and soil management and adopting high-yielding crop varieties must be improved to target regional agricultural efficiency. “But the proportions of nutrient-rich products in food imports must increase — alongside a reduction in restrictive trade policies which tend to raise food prices.”