Musicians Beyoncé and Jay-Z challenged their fans to go vegan in a forward the couple penned for new book The Greenprint: Plant-Based Diet, Best Body, Better World. “We used to think of health as a diet—some worked for us, some didn’t,” the couple wrote. “Once we looked at health as the truth, instead of a diet, it became a mission for us to share that truth and lifestyle with as many people as possible.” The Greenprint—a name that echoes Jay-Z’s hit 2001 album “The Blueprint”—is part of a multi-pronged project recently launched by vegan nutritionist Marco Borges, who co-founded vegan meal delivery brand 22 Day Nutrition with Beyoncé and Jay-Z in 2015. “We all have a responsibility to stand up for our health and the health of the planet,” the couple wrote. “Let’s take this stand together. Let’s spread the truth. Let’s make this mission a movement. Let’s become ‘The Greenprint.’” In addition to the book, Borges’ project aims to raise awareness about the benefits of consuming a plant-based diet through three initiatives, including a recently launched web tool, clinical study, and documentary featuring plant-based clinicians, celebrities, musicians, and athletes slated for release next fall. While neither Jay-Z nor Beyoncé identify as “vegan,” the couple frequently promotes plant-based diets for health and environmental benefits. Last year, Beyoncé eschewed all animal products in preparation for the Coachella Valley Music Festival and took to Instagram to urge her 112 million followers to do the same.