In the video titled Sharing a tough truth, the former two-time World Champion Freerunner says he has recently felt 'uncomfortable' in his body. As a result, he tried various approaches, including a raw vegan diet, urine therapy, and a 35-day water fast.
Shieff says he was 'waking up stiff' every day, with cracking joints, feeling 'desperate for health'. He says he didn't want to go to the doctors and felt he could resolve the issues by fasting, but didn't experience the benefits he had heard about. He followed the fast by a raw vegan diet, then cooked vegan diet - but in his words 'still didn't feel healed'.
Eggs and salmon
"So I went to Bays Farm down the road and bought a couple of eggs," he says. "I see the chickens running around, completely free chickens not just some supermarket thing, like really free. And I had a couple of raw eggs and I felt better. I did feel better.
"And I don't know why because you hear all these stats, you watch Dr. Greger videos about animal products and the damage...[and how they are] worse than smoking cigarettes, but for some reason it made me feel better.
"It sent me questioning everything. A few days later I bought some wild caught salmon and tried that...I wanted to speak, and I wanted to share this stuff but at the same time I think I'm still allowed my own space to try things...desperation led me to try that.
"There's so much more to health and healing, and health and the diet than nutrition. There's so much emotional involvement and other things as well. But I wanted to be honest and share that...I've come back to veganism, I just want to say sorry to the community."
Tim Shieff's video
As a result of his video, Shieff has received a slew of feedback - both negative and positive, with many people suggesting he seeks medical advice.
"Please get a blood panel," said YouTuber Mic the Vegan. "You don't have to do what doctors tell you to do if you don’t want but some concrete answers might be refreshing.?"
YouTuber Gojiman lost both parents and his sister to autoimmune diseases and has a genetic problem which means he can't metabolize drugs (i.e. antibiotics) normally, instead building up toxins in his body - leading him to feel unwell as Shieff does.
Explaining that he felt like he was 'literally dying and didn't know where to turn', Gojiman says he almost turned to a carnivore diet, but then found three tests which give details about the gut and cellular information that he describes as a 'lifesaver' for him. He asked Shieff to reach out to him so they can talk further and do the tests.
Shieff has also come in for significant criticism from some sections of the vegan community, with one social media user writing: "17 years ago today Barry Horne lost his life in the fight for animal liberation after his third hunger strike in prison.
"Today, Tim Shieff started eating eggs and fish 'for his health' and apologized to his 'fans' for this rather than the animals."
Others say Shieff's confession illustrates more widely spread issues: high profile vegan advocate Christopher Sebastian said it 'demonstrates the quiet ableism of health veganism advocacy' in an article posted on his website.
"Veganism has a long history of extraordinary claims including clearing your skin, dropping your trouser size, growing your hair, paying your taxes, folding the clothes, washing the dishes, walking the dog, beating the kids, and replacing your lover," Sebastian writes.
"But when people don't experience these alleged benefits, or worse - experience chronic or degenerative illnesses despite a plant-based lifestyle - this reveals the ableism of promoting health veganism, and it invalidates the thousands of vegans with bad skin, thick bodies, cancer, baldness, and more."
Gojiman's video supporting Shieff
Speaking to Plant Based News, Tim Shieff said he understood the criticism, and the depth of feeling behing it.
Addressing comments that he should have apologized to the animals, rather than the vegan community, he said: "I think it's a fair point and I understand that perspective and I agree that the animals absolutely deserve the acknowledgement more than the community.
"It was confusing with lots of conflicting emotions but it was a conscious choice that I prayed and gave thanks for.
"It was selfish. I am only human after all and that is one of the reasons my handle is 'HumanTimothy' on socials media."
PBN also asked Shieff about the pressure he felt in making the announcement. He said: "For sure I feel pressure, not only am I feeling a lot of pressure right now in light of the announcement, but I've realised that I've felt unbelievable amounts of pressure for six years: pressure to conduct myself flawlessly with my daily consumption of food, products and resources alongside sustaining myself mentally, spiritually and physically.
"Compounded with internet abuse, this takes its toll. It scared me to be public about this but that wasn't a reason to not speak on it. I got into veganism for the animals, for my health, and for Mother Earth and all three of those are in mind with every choice I make.
"When your health declines it is very hard to not make that the priority however selfish it appears to a healthy person."
Speaking about the support he's received, he said: "I've also had an immense amount of caring responses and I'm grateful for the understanding this crazy news has been met with.
"I saw Gojiman's video and appreciated how balanced and supportive he was, we've been in contact since for advice from him and I am seeking and taking it elsewhere too."
He concluded: "We need to remind ourselves that by the very nature of our existence we cause destruction, wether its an ingredient on our plate or not.
"It's impossible to track so we each do the best we can in our own way with our own understandings from lessons life gives us.
"Aspiring to protect and live in alignment with mother earth remains my goal and I've learnt that demanding constant perfection from ourselves and everyone around us can be damaging too."
This article was updated on November 6 to reflect Tim Shieff's comments.