http://www.newsweek.com/want-save-planet-go-vegan-study-says-952789

Adopting a vegan diet (free from animal products such as dairy, eggs and meat) is the best way to protect the planet, according to a major new study.

By carrying out the most comprehensive investigation yet into the environmental impact of food production, researchers found that even buying sustainably sourced meat or dairy didn't outdo the benefits of a plant-based diet. And unless there is a major change in how animal products are cultivated and manufactured, eating vegan food will be better for the planet in the foreseeable future than farmers tinkering with their methods.