The China study: The Most Comprehensive Study of Nutrition Ever Conducted and the Startling Implications for Diet, Weight Loss and Long-term Health is a book by T. Colin Campbell and his son, Thomas M. Campbell II. The book argues for health benefits of a vegan diet. It was first published in the United States in January 2005 and had sold over one million copies as of October 2013, making it one of America's best-selling books about nutrition.