Switching from red meat to mushroom-based alternatives for one in five meals could halve deforestation by 2050.
A German study found that fungi-based dinners could ‘massively benefit’ animal welfare, save water and reduce the pressure on land.
If meat-eaters made the switch just 20 per cent of the time it would also have a massive impact on greenhouse gases linked to farming of cows and sheep.
Dr Florian Humpenöder, of the Potsdam Institute for Climate Impact Research, said: ‘The food system is at the root of a third of global greenhouse gas emissions, with ruminant meat production being the single largest source.
‘The substitution of ruminant meat with microbial protein in the future could considerably reduce the greenhouse gas footprint of the food system.’
Research from the Potsdam Institute (PIK) modelled the future environmental effects of substituting ruminant meat with microbial protein, taking into account food demand and diets, population growth and land use.
With a growing population and increased meat consumption, more and more forests and other natural vegetation could be cleared for grazing and crop land.
But the projections, published in the journal Nature, show that substituting 20% of ruminant meat consumption per person with microbial protein by 2050 stops the increase in pasture areas needed for livestock grazing.
And while demand for sugar cane as a feedstock for fermentation of the protein increases, the need for animal feed crops is reduced.
The switch would cut annual deforestation and related carbon dioxide emissions by 56% compared with business-as-usual trends, the study estimates.
It would also lower emissions of other greenhouse gases including methane, and nitrous oxide from fertiliser or manure.
Dr Florian Humpenöder added: ‘The good news is that people do not need to be afraid they can eat only greens in the future.
‘They can continue eating burgers and the like, it’s just that those burger patties will be produced in a different way.’
Co-author Alexander Popp, leader of the land use management group at PIK, said: ‘A large-scale transformation towards biotech food requires a large-scale decarbonisation of electricity generation so that the climate protection potential can be fully developed.
‘Yet if we do this properly, microbial protein can help meat-lovers embrace the change. It can really make a difference.’