Barbara O’Neill, who makes a living as a holistic health educator, has given lectures claiming that cancer is caused by a fungus and that she has helped people cure their cancer with baking soda and highly restrictive diets, and discouraging those who listened to her from seeking chemotherapy. She has lectured that there are “no safe vaccines” and that pregnant women with Strep B do not need to take antibiotics.

For these reasons, Australia’s Health Care Complaints Commission found in late 2019 that O’Neill’s teachings posed a “risk to the health and safety of members of the public” and banned her from providing health services in the country for life.

Now, more than four years after that ban, it seems as though O’Neill and her discredited dangerous teachings have never been more popular. Just open up TikTok.

Clips of O’Neill’s lectures, which have circulated on YouTube, Facebook, and Instagram for years, can get millions of views on TikTok, where they are often used as the soundtrack for creators selling supplements and products in the TikTok Shop. One such video has more than 1.5 million views and urges viewers to drink water with a pinch of Celtic sea salt in order to improve hydration (it won’t). The video’s linked product listing for the salt has 3,600 sales. TikTok influencers earn money as affiliate marketers from sales linked to their content, and TikTok takes a small commission.

E-commerce platforms like TikTok Shop have become a rising source of health misinformation, said Alexandra Popken, the VP of trust and safety at WebPurify, a company that provides moderation services for several major e-commerce platforms (WebPurify does not moderate the TikTok Shop). Popken said that about 3 percent of the content WebPurify moderated in January was flagged as containing false or misleading health information. Often, she said, this is a result of sellers getting attention for products that don’t necessarily violate a platform’s policies by making outrageous or impossible claims about their benefits.

Health misinformation usually gets a lot of attention when it’s trending on social media or when a real-life consequence of bogus medical advice becomes a news story. In reality, though, this stuff is more unstuck in time, circulating in loops and patterns that catch attention and fade over and over. Protocols and “natural” remedies that were debunked decades ago are constantly finding new audiences online: in Facebook groups for managing illnesses, in anecdotes shared between caregivers, in circulated statements from politicians, in Instagram advice from wellness influencers, and, increasingly, on TikTok. Now, these ebbs and flows are giving new life to O’Neill’s lectures.

Why health misinformation takes off on TikTok

Vox previously wrote about affiliate videos — including some featuring O’Neill’s lectures — selling castor oil as a miracle cure on TikTok. While castor oil is an FDA-approved laxative and is used in some skin care products, it has become trendy as a remedy for a broader range of ailments, generally promoted with little evidence to back it up. A clip from O’Neill’s lecture on castor oil, which has already been debunked as untrue, is still used by some creators selling the oil in the shop. The video claims that castor oil can “heal any problems in the abdomen” if applied to the skin, including breaking up cysts and fibroids in the uterus. The same lecture claims that castor oil applications can help cure cancer in the brain and abdomen (they can’t).

Since writing that story in early October 2023, I’ve been tracking what products and health videos show up on my TikTok For You page. The vast majority of TikTok Shop videos I get at this point are recommendations for products that are popular “natural” cures and treatments (in part because I have indicated to TikTok through my engagement with these posts that I am interested in seeing more). Shortly after writing about the castor oil videos, my recommended videos shifted to those pushing wild yam cream as a menopause treatment or hawking soursop leaves as a treatment for cancer. Through these months, the presence of O’Neill audio clips has been a constant in this content.

TikTok reviewed several videos mentioned in this story and removed some of them for violating its policies. The platform’s community guidelines prohibit many forms of health misinformation, including those containing “misleading statements about vaccines, inaccurate medical advice that discourages people from getting appropriate medical care for a life-threatening disease, and other misinformation that poses a risk to public health.” TikTok says it monitors misinformation through a combination of technology, user reports, and information from third-party fact-checking partners.

There’s evidence that this increased attention isn’t just playing out on my For You page: Google search interest for O’Neill spiked in the summer of 2023 alongside the rise of the castor oil trend and has stayed elevated since then.

O’Neill was not immediately available to respond to an emailed request for comment on whether this search interest has translated to increased attention for her ongoing lecture circuit. Since her ban in Australia, O’Neill has continued to give talks abroad, including at natural health retreats in the US where attendees pay thousands of dollars to sit in on lectures and receive health consultations with her.

Many of those retreats are associated with the Seventh-day Adventist Church, of which O’Neill is a member. And while she does maintain an online presence with an official Facebook and Instagram account that appears to be managed on her behalf, most of the actual lecture uploads are done by third parties: retreats advertising their services or affiliation with her by sharing samples of her appearances at their facilities, companies selling products promoted in her teachings, or fans looking to get attention for O’Neill and her ideas.

Those searching for O’Neill are likely to find this content. Because TikTok recently decided to stop showing view counts for hashtags on its platform, it can be difficult to quantify the reach or influence of her lectures there. The top video for #barbaraoneill has 7.4 million TikTok views and is a clip of her talk claiming that castor oil can break up cysts, breast cancer tumors, gallstones, and bone spurs. Not all of the videos recommended to me use her name as a hashtag.

On YouTube, the top results for a search for her name bring up videos from Living Springs Retreat, an Alabama-based wellness clinic with a large online presence that regularly holds retreats with O’Neill present. Google results are only slightly better. A search run in incognito mode in early February for her full name pulled up a mix of first-page results that included links to her lectures, her books on Amazon, and her official website, but also surfaced a couple of articles about her ban from giving health advice.

The changing nature of misinformation

I’ve been thinking a lot over the past year about what misinformation means and looks like in 2024, as we approach a decade after the concept’s sharp rise into the collective consciousness of many Americans, and four years after the beginning of the Covid-19 pandemic. The rise of O’Neill’s lectures as health misinformation carriers on TikTok gives one illustration of its present reality: Bogus cures and dangerous health trends relentlessly pursue the people who are most vulnerable to their influence by finding ways to enter the algorithmic recommendations of the sick and searching, even if they are less visible to the platform’s user base at large. And once these trends get hold of someone’s feed, it can be difficult to shake them out.

From a moderation perspective, said Popken, the trust and safety executive, that can be “extremely challenging” to do well, especially if e-commerce platforms rely solely on content bans and keyword filtering to enforce their policies. She added, “They really need to be thinking about product design and the ways in which these algorithms are repeatedly surfacing this content and maximizing reach in a way that they shouldn’t be.”

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