Land use, even cropland use, is actually far lower on a plant-based diet

The research suggests that it’s possible to feed everyone in the world a nutritious diet on existing croplands, but only if we saw a widespread shift towards plant-based diets.

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If everyone shifted to a plant-based diet we would reduce global land use for agriculture by 75%. This large reduction of agricultural land use would be possible thanks to a reduction in land used for grazing and a smaller need for land to grow crops.

https://ourworldindata.org/land-use-diets

we show that plant-based replacements for each of the major animal categories in the United States (beef, pork, dairy, poultry, and eggs) can produce twofold to 20-fold more nutritionally similar food per unit cropland. Replacing all animal-based items with plant-based replacement diets can add enough food to feed 350 million additional people, more than the expected benefits of eliminating all supply chain food loss.

https://www.pnas.org/doi/abs/10.1073/pnas.1713820115

Also wanted to point vast majority of people consuming animal products contain a number of deficiencies in vitamins and minerals that only or mostly occur in plants. For instance, only 5% of the US population gets enough fiber

It is the position of the Academy of Nutrition and Dietetics that the public should consume adequate amounts of dietary fiber from a variety of plant foods. Dietary fiber is defined by the Institute of Medicine Food Nutrition Board as “nondigestible carbohydrates and lignin that are intrinsic and intact in plants.” Populations that consume more dietary fiber have less chronic disease. Higher intakes of dietary fiber reduce the risk of developing several chronic diseases, including cardiovascular disease, type 2 diabetes, and some cancers, and have been associated with lower body weights. The Adequate Intake for fiber is 14 g total fiber per 1,000 kcal, or 25 g for adult women and 38 g for adult men, based on research demonstrating protection against coronary heart disease. Properties of dietary fiber, such as fermentability and viscosity, are thought to be important parameters influencing the risk of disease. Plant components associated with dietary fiber may also contribute to reduced disease risk. The mean intake of dietary fiber in the United States is 17 g/day with only 5% of the population meeting the Adequate Intake. Healthy adults and children can achieve adequate dietary fiber intakes by increasing their intake of plant foods while concurrently decreasing energy from foods high in added sugar and fat, and low in fiber. Dietary messages to increase consumption of whole grains, legumes, vegetables, fruits, and nuts should be broadly supported by food and nutrition practitioners.

https://www.jandonline.org/article/S2212-2672(15)01386-6/fulltext