A plant-based diet is a "dangerous trend" for the environment, high-fat, low-carb diet pioneer Tim Noakes, advocate-in-chief of the Banting diet, said.
"The only way we will save the planet is by going back to eating meat," Noakes said.
He told HuffPost SA that an abundance of livestock agriculture could save the planet from the effects of climate change.
In the last few weeks, Noakes has been outspoken about his views on vegan and vegetarian diets on Twitter, where he regularly refutes claims made in the Netflix documentary "What The Health"–- which is frequently credited for a recent rise in veganism worldwide.
The documentary, which has topped the video-on-demand website's most-watched list for months, cites animal farming and a meat-based diet for global warming, and a rise in cancer.
"Topsoil is disappearing owing to plant-based agriculture... I worry that you can't continue like this much longer because the myth that livestock is driving environmental issues is driven by the fossil-fuel industry and they are very powerful, obviously," said Noakes.
"It would be unethical for doctors to prescribe a vegan diet to their patients."
"People like Bill Gates and Richard Branson are very powerful, and more people are saying they are going to be eating plant-based diets because of them.. but the move against meat-based diets is unfounded and irresponsible to promote at this stage."
The renowned sports nutritionist said it would be unethical for doctors to prescribe a vegan diet to their patients.
"There's never been a society that can survive on a completely vegetarian or vegan diet. We have to have some animal products. Vegan people survive because you can get some of the nutrition you need from supplements, which means it's not a complete diet," said Noakes.
"But you are still not getting adequate protein. You can survive on a 100% animal diet, but you cannot survive on a 100% vegan diet."
The Banting king said human evolution had created meat-eating beings.
"We became humans when we started to eat animal produce. When we became carnivores, we realised it was much easier to eat an animal than having to carry around this huge gut," he told HuffPost SA.
"What's happening now is that vegans and vegetarians are trying to convert the biology of humans to the way we were 3 million years ago, and we can't do that. There is one species that tried, the panda bear, and it is one of the unhealthiest animals on earth."
He claimed pandas suffer from bowel problems, obesity and lethargy, which was the same for vegans and vegetarians.
Noakes has been criticised for his outspoken views, with some saying his research was funded by meat, dairy and egg companies.
"I have no ties to the meat industry, that's ridiculous. People don't look at the current food we are eating. The plant-based, high-carb diet actually earns hundreds of millions a year, and I get nothing out of it," said Noakes.
"In fact, I wrote a book and donated the money to charities and foundations, so how can you accuse me of having an agenda?"
*In a previous version of this story Professor Tim Noakes was referred to as a dietician, he is in fact a professor in the department of Exercise Science and Sports Medicine at the University of Cape Town.