Almost quit beef due to the info in Cowspiracy in which I believe they pointed out that if everyone were to switch to grass fed beef there would literally not be enough grassland to support it (this is probably true, with the assumption that various plant crops continue their unsustainable land footprint). However, having seen also "The Magic Pill" on Netflix, I've concluded the optimal solution is probably more, healthier beef, and less plant agriculture land. The real problem isn't the cows, it's what the cows eat, which is mostly corn, soy, grains etc. Put as simply as I can: if humans committed to eating fewer carbs, and eating grass fed fatty meat and high quality plant oils for the bulk of their calories, the resulting system would produce huge carbon capture because grassland in its 'growth phase' is a very efficient carbon sink, and is more supportive of healthy soil than fields of corn, soy, and grains.