The special report on climate and land by the Intergovernmental Panel on Climate Change (IPCC) described plant-based diets as a major opportunity for mitigating and adapting to climate change, and included a policy recommendation to reduce meat consumption.
The report said that the West's high consumption of meat and dairy produce was fuelling global warming. But scientists and officials stopped short of explicitly calling on everyone to become vegan or vegetarian.
They said that more people could be fed using less land if individuals cut down on eating meat, the BBC reported.
"We're not telling people to stop eating meat. In some places, people have no other choice. But it's obvious that in the West we're eating far too much," said Prof Pete Smith, an environmental scientist from Aberdeen University, the UK.
The document, prepared by 107 scientists for the IPCC, said that if land was used more effectively, it could store more of the carbon emitted by humans.
The report came months before negotiations at the UN's annual climate conference in Santiago, Chile in December.
"Sustainable land management can contribute to reducing the negative impacts of multiple stressors, including climate change," said the report, approved after five days of meetings with scientists at the 50th Session of the IPCC.
"Several solutions can be used to provide some respite in the short, medium and long term," experts added.
The extensive analysis urged governments to lay down policies to change the agricultural and forest use of land to tackle climate change, keeping in mind that the forests absorb about a third of the carbon emissions.
"Such policies can contribute to climate change adaptation and mitigation, reduce land degradation, desertification and poverty as well as improve public health."
The report warned that plans by some governments to grow trees and burn them to generate electricity will compete with food production unless carried out on a limited scale.
The report, for the first time, established a direct link between climate change and land degradation - more arid areas, the threat to biodiversity, desertification - and warned of an increase in droughts in areas such as the Mediterranean and southern Africa due to global warming.
The effects of climate change could also increase the risk of forest fires and pest infestations, according to the IPCC report.
( With inputs from IANS )