Millions of lives could be saved every year through healthier lifestyles if countries hit their targets under the Paris climate agreement, according to a new study.
The research focused on potential changes in nine major economies up to 2040 leading to cleaner air, increased exercise and better diet with more fruit and vegetables and less red meat.
The improvements rely on the countries – representing half of the world's population and 70 per cent of its emissions – limiting global warming to the target of "well below 2°C" from the 2016 Paris Agreement, according to the study published in the Lancet Planetary Health journal.
The research was based on projections of six of the top 10 most populous nations – China, India, the United States, Indonesia, Nigeria and Brazil – with Germany, the UK and South Africa. Changes built into the calculations included reductions in car use that would lead to more people cycling, walking and running to work.
It calculated that 6.4 million people a year would live longer as a result of better diets, 1.6 million from cleaner air and 2.1 million from increased exercise.
The most significant effects of changes in diet were likely to be in Germany, followed by the US and China, the study found.
The modelling relies on changes of production, technology and lifestyle to reflect more people taking up a semi-vegetarian, or flexitarian diet, because of greater availability of fruit and vegetables and reduced consumption of red meat and processed foods.
But researchers said that for this to happen, more ambitious action was required from governments to reach their climate change targets.
Since the analysis was completed, the UK and EU have strengthened their goals, US President Joe Biden said climate change was a key focus for his administration and China has committed to achieving carbon neutrality by 2060. But the world is still heading for warming of 2.5 per cent between now and the end of the century, the study said.
Lead author of the study, Ian Hamilton, said: “Our report focuses on a crucial but often overlooked incentive for tackling climate change.
“The message is stark. Not only does delivering on Paris [agreement] prevent millions dying prematurely each year, the quality of life for millions more will be improved through better health.”
The UK is scheduled to host the latest global climate change summit in November, aimed at “accelerating action” to tackle the crisis.