Smalling made the plea as part of a campaign for animal rights charity PETA.
The star created a poster for the organization, which features him sinking a deft mid-air kick to shield a group of animals, and says: "Be Their Biggest Defender. Try Vegan!"
Vegan football player
Smalling made an accompanying video for the campaign, in which he talks about life without animal products.
"I've been vegan for about a year," the defender says in the video. "As athletes we're constantly striving for the best, but ultimately, it was the animal welfare that [made me sure] that this is my life now."
Smalling shared some of the questions he gets asked about being vegan, including (of course) where he gets his protein from, where he gets his strength from, and how he runs for 90 minutes. "The proof's in the pudding," he says, "because I clearly get all those. I had a lot of tendinitis in my knee, and then once I went fully vegan, all those symptoms just dropped away."
Speaking about the horrors of animal agriculture, he adds: "I realized how brutal [animal agriculture] is to animals, how unnecessary it is to us, and how damaging it is to the environment."
The athlete talks about being vegan
In a statement sent to Plant Based News, PETA adds: "Going vegan would give football fans the opportunity to enjoy many more matches, as cutting out meat, eggs, and dairy lowers our risk of suffering from heart disease, diabetes, cancer, obesity, and numerous other life-shortening health concerns.
"Each person who goes vegan also dramatically reduces his or her carbon footprint – and spares nearly 200 animals every year daily suffering and a terrifying death in today's meat, egg, and dairy industries.
"Smalling is part of a growing list of vegan sports stars – including five-time Formula 1 champion Lewis Hamilton, boxing world champion David Haye, tennis star Venus Williams, and fellow footballer Héctor Bellerín."