The list was created using an algorithm which looks at influencers' account audience size, growth, and engagement rate.
Oakley - who is known as Avant Garde Vegan on social media - clinched the number 18 spot. Number one went to YouTuber Pewdiepie. The top 100 list featured multiple gaming channels and beauty 'gurus', alongside a range of other genres.
'Can't believe it'
"I can’t believe I was featured in the list," Oakley told Plant Based News. "When I first posted a recipe on Instagram I never imagined gaining an audience of the size I have, especially on YouTube.
"It’s an honor to be able to use my cooking skills to promote a cause that means so much to me, veganism.
"Being amongst so many talented influential people on this list is a great feeling. Huge thanks to my team that help me produce beautiful content, and to my subscribers on YouTube and Instagram followers for the support."
According to the Sunday Times' list: "Gaz Oakley is a chef, author, food blogger and vlogger who shares his vegan recipes on Instagram, his website and YouTube channel under the name Avant-Garde Vegan.
"He has written two cookbooks and has worked with Wagamama to create a vegan dish for its menu, which was launched in 2018.
"Originally from Cardiff, Gaz studied catering and worked in restaurants until the age of 20, when, feeling burnt out, he changed careers and took a sales role. His love for cooking was reignited in 2016, after becoming a vegan and starting to share recipes on Instagram."
Other plant-based figures to make the list include fitness vloggers Grace Beverley (26) and Zanna van Dijk (80), and foodie Ella Mills.