If anyone is still searching for a New Year's Resolution superstar couple, Beyoncé and Jay Z have got for you to try: Veganism. The powerful double act have written an introduction for Marco Borges' (Beyoncé's trainer) new book, The Greenprint: Plant-Based Diet, Best Body, Better World and, in it, they're challenging their fans to cut out any and all meals centred around animals.

Beyonce and Jay ZBeyonce and Jay Z are promoting veganism

This isn't the first time Beyoncé has spoken out about a vegan diet after the mum-of-three told her millions of Instagram followers she was going strictly vegan in preparation for her Coachella performance.

Beyoncé, 37, had 44 days to get back into shape following the birth of her now 18-month-old twins, Rumi and Sir, and it seems like she had nothing but a positive time while on the plant-based diet.

Now her and husband, Jay Z, 49 - who also share six-year-old, Blue Ivy - appear to be embracing the new lifestyle more regularly.

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According to PEOPLE, the multi-award winning couple wrote: "Having children has changed our lives more than anything else.

"We used to think of health as a diet - some worked for us, some didn’t. 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 pair said they "want to challenge you, as we challenge ourselves".

And added: "We all have a responsibility to stand up for our health and the health of the planet. Let’s take this stand together. Let’s spread the truth. Let’s make this mission a movement. Let’s become 'the Greenprint."

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However, Bey and Jay aren't expecting anyone to stick veganism all day, every day, or change their lifestyle overnight.

Instead, their current 'mission' is to convince people to incorporate more plant-based meals into their usual diets, which they say is enough to bring about a "profound impact on our health and the environment."

According to researchers at the University of Oxford, veganism is in fact the 'single biggest way' to to reduce your carbon footprint and impact on the environment.