Often times it is even stated that factory-raised beef is not less healthy from a personal standpoint. However, the environmental impact is not mentioned, much less emphasized. Taking the source of the meat into consideration, the majority of people are probably not willing to spend the money necessary to raise those animals in the proper way. Which is the proper way? If ruminants are raised out on pasture and eat only fresh grass, this is a sustainable and even regenerative way. It is indeed possible to sequester more carbon from the atmosphere and store it in the soil long-term, than what is released during the rest of the supply chain, from farm to table.
I am optimistic that people see this issue with the carnivore diet and put the health of the planet above their personal hopes of achieving improved health, which is in fact very questionable. Many long-lived populations show us that it is possible to live very healthily on a primarily plant-based diet. Not exclusively, but as a large percentage of caloric intake. And if, and this is a big if, those plant calories are sourced locally, seasonally, and from non-mono-cropped fields, they can be cheaper and more sustainable than pasture-raised meats. This of course also requires a huge shift in consumer thinking and habits. This is unlikely to happen in the general population without national/global incentives.
Consumption of regular meat is the most resource-intensive and environmentally harmful food. Even though many of the claims coming out of the vegan community are largely exaggerated, this type of meat still consumes more resources than eating the grains, legumes, tubers, etc. directly. We can only digest starches and sugar, but ruminants are also able to extract energy from fiber. They can therefore digest the whole plant, which makes the resulting caloric calculation a little more favorable.
But the biggest negative impact comes from the mono-cropped fields, from tilling the ground and exposing the soil. This is true for grain-fed meat as it is for all other foods grown in this fashion that we consume directly. Therefore, whether you decide to eat meat- or plant-based, you have to ask how the primary plant, that has captured the sunlight and turned it into a stored form of energy, is grown. During this process, is the soil exposed or tilled, are the fields sprayed with pesticides, and is the whole process carbon positive or negative.
I critique the carnivore movement because it has fallen into a similar trap as the vegan movement. In its thinking it only goes one level deep. But considering the process of growing food holistically is important to make sound food-decisions with consideration of its environmental impact. And for that, it is not enough to just look at the food directly. There are many layers to the impact food can have. A complete analysis includes also the impact of the production of fertilizers and pesticides, the machinery and its gas consumption, processing, shipping, and storage.
Considering all the above, fresh, local, pasture-raised meat can be one of the most environmentally friendly foods we have. At least in many parts of the world and especially in regions where the climate and soil quality does not allow for crop production. CAFO-raised, imported, corn- and soy-fed (from deforested land) meat on the other hand is the most environmentally harmful food available. Meat is not meat.
"It's not the cow, it's the how." - Bobby Gill