Researchers have linked dietary data from over 55,000 individuals with data on the environmental impacts of the foods they eat. The team, from the Livestock, Environment and People (LEAP) project at the University of Oxford, found that the dietary impacts of vegans were around a third of those of high meat eaters. They also saw a 30% difference between high- and low-meat diets for most of the measures of environmental harm.
I’m pretty sure I read a meta analysis that concluded that a little meat is better than no meat. But that hardly matters bc when you tell someone about paleo they end up shoveling chicken, beef, and dairy down their throat with little to no vegetables and fruits (I think from the same analysis)