A vegetarian for the past four decades, Paul McCartney has released a booklet to promote his Meat-Free Monday campaign, which encourages people to refrain from consuming animal products one day each week to promote a healthier and greener diet

“We tend to think that what we have always done is what we always will do in the future, " he says,  "How boring is that? Can’t you look at your life and go, ‘You know what? I think I might fancy a change.'”

The 74-year-old star first launched his campaign in 2009 with his daughters Mary and Stella McCartney.

Actor Kevin Spacey has also jumped on the bandwagon and adopted McCartney's mission. 

“Having one designated meat free day each week is an easy way to help protect the planet, " said Spacey. "There’s nothing to lose by supporting Meat Free Monday but a great deal to gain.”

Other celebrity endorsements came from designer and noted animal rights activist Vivienne Westwood, and actress Joanna Lumley who's also vowed to adopt the new lifestyle after being inspired by the campaign.

“Just see how easy it will be not to eat meat for one day a week. Just think how the world will benefit from fewer trees being cut to make way for grazing animals", Lumley said.

"Just imagine how many lives, both animal and human you will help to save: and join the fab Paul McCartney and millions more, including me, in making Monday a Meat Free day".