Beyonce
Beyonce launched a vegan meal delivery service called 22 Days Nutrition, with her trainer Marco BorgesTheo Wargo/Getty Images for Global Citizen

The annual event dedicated to being kind to the planet is celebrated on 1 November and an estimated 150,000 people in the UK are vegan. World Vegan Day was established in 1994 by Louise Wallis, who was president and chair of the The Vegan Society in the UK.

"We knew the Society had been founded in November 1944, but didn't know the exact date, so I decided to go for the 1st November," Wallis said. "Partly because I liked the idea of this date coinciding with Samhain/Halloween and the Day of the Dead - traditional times for feasting and celebration. Both apt and auspicious."

Why go vegan?

According to reports released by the World Health Organization, processed meats rank alongside cigarettes as a major cause of cancer. "For an individual, the risk of developing colorectal cancer because of their consumption of processed

meat remains small, but this risk increases with the amount of meat consumed," says Dr Kurt Straif, Head of the IARC Monographs Programme. "In view of the large number of people who consume processed meat, the global impact on cancer incidence is of public health importance."

According to the findings, 50g of processed meat a day – the equivalent of one sausage or less than two slices of bacon – increases the chance of developing bowel cancer by 18%. Coronary heart disease, which is linked to a meat-based diet, is the leading cause of death in the UK. On average, 224 people die of heart disease in this country each day.

The word vegan is no longer seen as a weird health fad or a term of derision. It has gained in popularity as a meat and dairy-free diet that is now healthy, ethical and fashionable. "A vegan diet, rich in fruits and vegetables, is full of antioxidants which help protect the body from damage by free radicals," says Dr Neal Barnard, author of 21-Day Weight Loss Kickstart. Ellen DeGeneres and Portia de Rossi kickstarted the trend for vegan weddings, treating their guests with vegetable spring rolls and faux-beef mini-burgers at their nuptials.

Famous vegans

Becoming vegan is increasingly popular among celebrities. Luxury fashion houses such as Stella McCartney and Joseph Altuzarra have already featured artificial or 'vegan' leather in their catwalk shows.

Jessica Simpson

She became a temporary vegan, cutting out animal products in the fortnight prior to her wedding. "Jessica did a vegan diet for about two weeks... She also got quite a few B12 shots," a source told Us Weekly.

Jennifer Lopez

The singer and actress claims that her vegan diet has given her plenty of energy. : "Being vegan, it's basically no dairy, no meat, everything is just plant based and just from the ground...I love that I'm eating more greens. It makes you feel so much better." But there is one thing she misses most of all. "Butter is the one thing I miss! Butter makes everything taste better."

Jay-Z

A surprising announcement was the rapper saying he intended to go vegan on his Life & Time blog in December 2013. "On December 3rd, one day before my 44th birthday, I will embark on a 22 Days challenge to go completely vegan, or as I prefer to call it, plant-based!! I will post my progress... Any professional vegans out there that have any great food spots please help out! Please ha. I don't know what happens after Christmas. A semi-vegan, a full plant-based diet? Or just a spiritual and physical challenge? We'll see..." The rapper also added that his wife Beyoncé is also partaking and has launched a vegan meal delivery service called 22 Days Nutrition, with her trainer Marco Borges.

Tobey Maguire

Did you know that Spiderman was vegan? Well, at least the actor who plays him on the big screen is. Maguire became a vegetarian in 1992 and a vegan in 2009. In a 2008 interview with Parade magazine, the actor revealed giving up meat was an easy adjustment, saying: "It's never really been that hard for me. I've never had any desire to eat meat. In fact, when I was a kid I would have a really difficult time eating meat at all."

Lea Michele

The Glee star extols the healthy lifestyle and feels it's the right ethical choice. "It's about being good to your body and the planet. I'm a foodie, but I think it's much more fun to find things on the menu that are good for me," she said. Michele was honoured by PETA in 2010 for her charity work with animals.

Jared Leto

The singer and actor attributes has youthful good looks to a vegan diet and yoga workouts. The 43-year-old said he and his band mates in 30 Seconds To Mars are all strict vegans. "Well, there was a time when we used to sacrifice goats, but then we all became vegans, so we've been sacrificing tofu before the shows!"

Jamie Hince

Kate Moss's ex described himself as a "chain-smoking vegan" but that was until he got together with the supermodel. "I was vegan for about 20 years," he told the Evening Standard. "The thing that really tipped me over the edge was when I first met Kate, had just started seeing her, and I walked into the kitchen and she was in her underwear making me a bacon sandwich. She didn't know I was vegan..."