Health and climate co-benefits of dietary change

By 2050, greenhouse gas (GHG) emissions related to agriculture and food production are likely to increase by more than 50 per cent, from 7.6 to 11.4 gigatonnes CO₂ equivalents, according to research led by scientists at the Oxford Martin School in the UK. However, shifting to a mostly vegetarian diet, or even simply cutting down meat consumption to within accepted health guidelines, would significantly reduce GHG emissions.

While energy generation, transport and heating of buildings have long been a target for climate policy measures, the impact from food production has often been left out. But on current trends, with intensive agriculture increasingly geared towards livestock rearing, food production will be a major concern.

Adhering to health guidelines on meat consumption could cut global food-related emissions by nearly a third in 2050, as compared to the reference scenario, i.e. down to 8.1 gigatonnes.

Widespread adoption of a vegetarian diet, including eggs and dairy, would halve emissions to 4.2 gigatonnes, while a vegan (i.e. completely plant-based) diet would achieve an emissions cut of around two-thirds, resulting in 3.4 gigatonnes CO₂ equivalents in 2050.

Such steps would also save lives, argued Dr Marco Springmann, lead author of the study that was published in the Proceedings of the National Academy of Sciences in April.

“Imbalanced diets, such as diets low in fruits and vegetables and high in red and processed meat, are responsible for the greatest health burden globally and in most regions,” he said. 

More than 5 million premature deaths could be avoided globally by 2050 if health guidelines on meat consumption were followed, rising to more than 7 million with a vegetarian diet and 8 million for veganism. These steps, if widely followed, could also reduce global healthcare costs by US$ 1 billion a year by mid-century.

Using the value-of-a-statistical-life approach, the overall economic benefits of improving diets were estimated at US$ 20–30 trillion per year in 2050, amounting to between 9 and 13 per cent of the global GDP in that same year.

Linking health and climate change in challenging our eating habits could have more effect than focusing on each of these issues alone, said Springmann. “By combining the two benefits, you have a more powerful impact. I think this will make more of an impression.”

“We do not expect everybody to become vegan. But the climate change impacts of the food system will require more than just technological changes. Adopting healthier and more environmentally sustainable diets can be a large step in the right direction.”

Reference: M. Springmann, H. C. J. Godfray, M. Rayner, and P. Scarborough (2016) Analysis and valuation of the health and climate change cobenefits of dietary change.

Source: The Guardian, 21 March 2016

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