Healthy eating guidelines not eco-friendly enough, say scientists

If the world went vegan, however, carbon emissions would be cut by 70%, 8.1 million deaths would be avoided annually and there could be economic benefits in excess of €938 billion per year.

The study, carried out by the Oxford Martin Programme on the Future of Food and published in the journal Proceedings of the National Academy of Sciences​, also puts figures on the benefits of a switch to vegetarian diets – a shift that could see greenhouse gas emissions slashed by 63% and 7.3 million deaths avoided. The economic benefits would be in the region of €855 billion.

Approximately half of the avoided deaths would be due to reduction of red meat consumption, with the other half down to a combination of increased fruit and vegetable intake and a reduction in calories, leading to fewer people being overweight or obese, the researchers said.

The values are subject to “significant uncertainties​”, the team noted, but they are likely to be an underestimate, given that they couldn’t model the health consequences of all changes in consumption – the health benefits that come from red meat being replaced by nuts and grains, for example.

But the report’s lead author, Marco Springmann, is under no illusions that such a significant dietary shift will take place – even within the next 35 years. “We do not expect everybody to become vegan,” ​he said.

What his findings demonstrate, however, is that diets will have to change if there is any chance of keeping temperature rises within two degrees. But critically, so too will the dietary guidelines set by governments.

Indeed, Springmann and his colleagues also modelled the environmental and health impacts of a future in which dietary guidelines are followed. This assumed the implementation of World Health Organisation global dietary guidelines on healthy eating, for example, and that people consume just enough calories to maintain a healthy body weight.

In that scenario, carbon emissions would only be reduced by 29% by 2050, though 5.1 million deaths would be avoided. This still wouldn’t be without headaches: fruit and vegetable production and consumption would have to be doubled in places like South Asia; whilst in East Asia and high and middle-income countries in the West, red meat intake would need to fall by two thirds.

Big challenges​

That is a significant challenge, with governments notoriously reluctant to tackle the issue of meat consumption, at least in relation to climate change.

Last month, the UK government updated its dietary guidelines with a newEatwell Guide​​, but critics said it didn’t go far enough in terms of reducing meat consumption. The Netherlands have gone much further – its updated advice last week recommended a halving of red meat consumption, which sustainable food experts hailed as “a breakthrough​​”.

Perhaps putting a euro value on the benefits will help? “Our ​results​​​ indicate that dietary changes could have large benefits to society, and the value of those benefits makes a strong case for increased public and private spending on programmes aimed to achieve healthier and more environmentally sustainable diets,”​ said Springmann.    

The scale of the task is “clearly enormous,​” though. “Climate change impacts of the food system will be hard to tackle and likely require more than just technological changes,” ​he added.

Analysts at VisionGain recently predicted​​ that heightened health concerns and increased environmental awareness would drive the meat substitutes market past the €3.5 billion mark next year.