What is a sustainable diet? It’s a question the government is yet to answer but can it hold out much longer?
“Imbalanced diets, such as those low in fruits and vegetables, and high in red and processed meat, are responsible for the greatest health burden globally and in most regions,” says Dr Marco Springmann from the Oxford Martin Programme on the Future of Food.
“At the same time the food system is also responsible for more than a quarter of all greenhouse gas emissions, and therefore a major driver of climate change.”
Springmann has led a study to assess the impacts of our diets and the benefits if we are encouraged to change them. He used a number of different scenarios and here’s what he found:
- If people followed dietary guidelines (which they don’t), 5.1m deaths could be avoided by 2050, whilst greenhouse gas emissions would fall by 29%
- If everyone goes vegetarian, avoided deaths would rise to 7.3 million and GHG reductions would be 63%
- Go a step further and turn everyone vegan and it would avoid 8.1 million deaths and slash emissions by 70%.
Springmann has also put price on the benefits of this huge dietary shift. The economic benefit of reduced greenhouse gas emissions from dietary changes ranges from £166 billion (following dietary guidelines) to £404 billion (vegan). He also totted up the savings from healthcare, unpaid informal care and lost working days – savings ranged from £522 billion (following dietary guidelines) to over £700 billion (vegan).
“We do not expect everybody to become vegan,” explains Springmann. That’s a relief. However, what’s clear is that adopting global dietary guidelines will not be enough to reduce food-related greenhouse gas emissions to keep global temperature increases to below 2°C.
Indeed, the UK’s new dietary guidelines just published by Public Health England (PHE) have a lower environmental footprint than current consumption patterns but go nowhere far enough if the country is to meet its (legal) commitment to cut emissions by 80% by 2050, according to the Carbon Trust.
PHE commissioned the Trust’s analysis, but there wasn’t any chance of the findings causing the government’s nutrition advisors into a rethink. The need to reduce meat consumption is mentioned but certainly not pushed.
The disconnect between policies remains, with the government reluctant to consider health and environmental issues together and, in turn, consider what a truly sustainable diet might look like.