We need a shift in global diets if we want to reduce our environmental impact: With agricultural expansion continuing to dwarf reforestation efforts and Nature-based Solutions (NbS) to climate change, changing what we eat is going to be key in reducing carbon emissions and staving off global warming, WWF Global Food Lead Scientist Brent Loken writes for the World Economic Forum. “Planet-based” diets (not to be confused with plant-based) can offer a solution, by encouraging the consumption of healthy, locally produced food in moderation to reduce the environmental impact of our eating habits.

What are nature-based solutions? NbS are environmentally-conscious solutions to a range of issues, inspired by nature and designed to address major societal challenges like food security, climate change, water security, and social and economic development. Examples include restoring and protecting mangroves and coral reefs that act as a natural barrier to shoreline erosion, or adopting “nature-positive” farming methods, to ensure the increased storage of carbon in soil and farmlands. NbS were one of the most discussed topics at the 2019 UN Climate Action Summit.

Sounds great. But why aren’t they working to mitigate climate change? The challenge is balancing reforestation and food security, and the issue comes down to is the finite available land. While nature-positive farming methods can reduce the environmental impact of food production, they will still drive an increase in demand for land if trends in food consumption patterns continue. There will only be enough land for reforestation at scale if we “halt agricultural expansion and reduce the amount of land currently used to produce food,” writes Loken. Roughly 50% of all habitable land is currently used for agriculture, and of that land, 77% is used to grow feed for livestock. In order to reduce our demand for more arable land, we need to reduce our consumption of meat and dairy.

Enter planet-based diets: If everyone adopted a planet-based diet — largely dependent on eating food that is high in nutritional benefit, but low in environmental impact — the WWF estimates we can cut food-related emissions by at least 30% and reduce agricultural land use by at least 41%. That could make a significant difference: food-related emissions account for 27% of all greenhouse gas emissions.

Cutting out meat is not necessary, but reducing its consumption is essential: Animal source foods don’t have to be eliminated altogether, but animals should be reared on natural grasslands instead of fed with crops grown on deforested land. The OECD-FAO 2020-2029 Agricultural Outlook estimates that rising national GDPs will drive an increase in global meat consumption of 12% by 2030, with continued growth until 2050. This will nearly double food-related greenhouse gas emissions. Reducing our meat intake will also have a positive impact on our collective health, with the WWF estimating that 20% of premature deaths could be avoided if people ate planet-based.

We will also need to dramatically optimize crop yields and adopt new farming methods to meet the demand of a projected global population of 10 bn by 2050. Our current methods require additional water and fertiliser, though global freshwater supplies are already under strain, and nitrogen and phosphorus pollution “already greatly exceed planetary boundaries in some locations,” according to the WWF report.

A full range of policy levers will be needed: Relying on awareness and educational initiatives will not be suffiences, writes Loken. These must also be accompanied by regulatory or fiscal measures to ensure widespread adoption of healthy and sustainable diets. Shifting to a plant-based diet will look different depending on where you are, and while it could reduce biodiversity loss in some countries, it may lead to unexpected impacts in others.

You can calculate the impact of your own dietary shift with this calculator from the World Wildlife Fund, which will give you country-specific results and impacts.