Organisers of 'Veganuary' predict 2021 will be their biggest year yet, with an increase in people trying out plant-based foods during lockdown.
The UK-based campaign asks people to pledge to follow a diet free from animal products during January, to achieve a "more compassionate and sustainable world".
Organisers are hoping 500,000 people will sign-up to its annual month-long veganism pledge in 2021 - a record 400,000 signed up in 2020.
More than 440,000 people have already signed up to take part this year, with sign-ups continuing at a rate of one person every three seconds.
If 350,000 people worldwide give up animal products for a month, the UK Vegan Society estimated that more than one million animals will be saved - that's close to three animal lives saved per person.
Since launching in 2014, the numbers have been growing - 250,000 signed up in 2019 and 170,000 in 2018.
One in five people in the UK were eating more vegan food as a result of the coronavirus pandemic, a survey by The Vegan Society found in April.
The majority of surveyees (43 percent) chose to reduce their meat consumption out of concern for health, environmental or animal rights reasons.
While the majority of people sign up to Veganuary for health reasons (38 percent), other reasons to participate include animals (37 percent), the environment (18 percent).
Compared to omnivorous diets, vegetarian diets are associated with lower blood pressure, and consuming a mostly or exclusively vegan diet can be beneficial for the prevention and treatment of hypertension.
Many multinational companies, including Nestlé, are backing the campaign.
Marco Settembri, the chief executive of Nestlé in Europe, Middle East and north Africa said: "A well-planned plant-based diet can meet nutritional needs during all stages of life while there are environmental and health benefits too.
"This year I am passing the baton and encouraging all employees to participate in Veganuary and sign up to the challenge. I am happy to be part of this movement as it grows across Europe and beyond."
A study by the National Academy of Sciences shows that if the world went vegan it could save 8 million human lives by 2050 and reduce greenhouse gas emissions by two thirds.