Plant-based diet shift can cut food-based emissions considerably

There are many reasons consumers may choose to follow a plant-based diet. Some do so for the potential health benefits plant-based foods confer; others choose not to eat animal-based products due to ethical concerns. And still others choose to eschew animal products out of concern for the environment and the impact food-related practices have on long-term climate outcomes.

Recently, a study published in Nature Food quantified the environmental impact of switching to a plant-based diet, and the results were considerable (Volume 3, 29–37 [2022]).

The study focused on 54 “high-income” countries representing, according to the authors, 68% of global gross domestic product and 17% of the global population. These countries included the UK and U.S., as well as Australia, France, Germany and others, and examined the impact on carbon footprint if residents of these countries adapted the EAT-Lancet Commission’s plant-forward diet. Such a diet focuses on grains, fruits, vegetables, nuts and legumes while limiting—though not fully eliminating—meat and dairy products.

The authors found such a transition to plant-forward diets would have a sizable impact on global agricultural emissions.

“Our results show that such dietary change could reduce annual agricultural production emissions of high-income nations’ diets by 61% while sequestering as much as 98.3 GtCO2 equivalent, equal to approximately 14 years of current global agricultural emissions until natural vegetation matures,” the authors concluded. They went on to note, “This amount could potentially fulfil high-income nations’ future sum of carbon dioxide removal (CDR) obligations under the principle of equal per capita CDR responsibilities.”

This study is just the latest to link plant-forward diets to smaller carbon emissions and a decreased footprint. In November, a UK study indicated meat production accounted for nearly one-third (32%) of diet-related greenhouse gasses (PLOS ONE 16[11]: e0259418).  

“Those who met dietary recommendations had generally lower diet-related [greenhouse gas] emissions, suggesting future policies to encourage sustainable dietary patterns and plant-based diets could be good for both individual and planetary health,” the authors of that study concluded.

“To move beyond general advice at the population level to specific advice tailored to the individual requires measures of environmental sustainability applied to a comprehensive range of specific food items at a more granular level,” those authors noted. It should be no surprise, then, that continued study on the impact of diet choices on the environment is necessary.

Another study published in Nature Food in September indicated meat production could be even worse for the environment, noting it could account for nearly 60% of global food-related emissions (Volume 2, Sept. 2021:724–732). On the other hand, the authors found, growing and producing plant-based food for human consumption generates half the emissions, or about 29% of the food system’s total. Those authors estimated food production accounts for about 35% of all global emissions, generating 17.3 billion metric tons of greenhouse gases every year.