Is this a celebrity fad?
"We all have a responsibility to stand up for our health and the health of the planet", they continued.
She is joined by fellow singers Miley Cyrus and Ariana Grande in promoting veganism, which prohibits consumption of all animal products, including meat, dairy items, eggs and honey.
The Greenprint, a plant-based holistic lifestyle plan, was developed by their trainer Marco Borges, and Beyoncé and Jay-Z were the first to try the plan out after learning about the benefits of a vegan diet.
According to the contest's mechanics, winners get up to 30 years of free concert tickets to the couple's shows, with a limit of one concert per tour.
Beyoncé said she is offering free lifetime tickets to any of her or Jay-Z's shows.
On 31 January the pop star announced a contest with vegan-based meal service 22 Days Nutrition, which invites fans to see the impact of eating plant-based.
Jay Z and Beyonce perform at the Global Citizen Festival on 2 December 2018 at the FNB Stadium. The site, which is hosting the competition, encourages entrants to cut down on meat-or even go full vegan-to help protect the environment. "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 competition is only open to those living in the United States but will give tickets to the victor for up to 30 years - and they get to take a guest.