On TikTok Shop, users can now purchase a supplement that will purportedly “bulletproof your immune system.” The product was “founded” by a group that includes Mikki Willis, who has falsely claimed that measles is a “bioweapon” and said he has been “working with” Health and Human Services Secretary Robert F. Kennedy Jr. Willis is also known for creating the viral film Plandemic, which pushed conspiracy theories about COVID-19.

TikTok Shop’s policies prohibit the sale of “medicinal supplements,” including “unlicensed medicines, herbal or homeopathic products, and those making health claims.” But that isn’t stopping the creators of Fierce Immunity from selling their supplement on the platform and suggesting that people who take it “don’t get sick.”

Fierce Immunity is a supplement claiming to “supercharge your immune system”

Fierce Immunity is billed as “a synergistic blend of bioactive compounds, precision-engineered to supercharge your immune system” and “a powerful blend of Vitamin D, Zinc Ascorbate, Quercetin, Hesperidin, and L-Arginine designed to fortify your immune system, reduce inflammation, and support rapid recovery.”

The supplement was created by a group that includes medical misinformers, and it was reportedly formulated with an “AI technology,” known as Swarm Intelligence. Fierce Immunity is also the first item listed in parent company Rebel Lion’s “Measles Protocol.” As part of the protocol, Rebel Lion claims Fierce Immunity works as “both prevention and response in times of viral threat.”

Health care experts have said that while some people can benefit from a vitamin D supplement, most people do not need vitamin D supplements because they get sufficient vitamin D from their diet and lifestyle. And while zinc plays a role in immune health, supplements are usually necessary only for people with zinc deficiency. In fact, some experts say excessive zinc levels can actually be “dangerous to your health.”

In small print, Fierce Immunity's website admits, “Fierce Immunity is not intended to diagnose, treat, cure or prevent any disease. … You should not use the information contained herein for diagnosing or treating a health problem or disease, or prescribing any medication.”

Rebel Lion is selling and promoting Fierce Immunity on TikTok

Rebel Lion is selling Fierce Immunity on TikTok Shop, even though the platform prohibits the sale of “unlicensed medicines, herbal or homeopathic products, and those making health claims.” In fact, the company is selling the product on the platform at half of its usual price of $58 a bottle.

On its TikTok account, Rebel Lion has posted videos of people making some bold claims about Fierce Immunity, such as saying it will “bulletproof your immune system” and “lock it down, supercharge it, and surround it with piranhas,” “It shields my immunity. I don’t get sick,” and “Two years ago I began taking Fierce Immunity … and in that two years, I haven’t been sick, not even a sniffle.” In another video, a man is repeatedly hitting a tire in a gym with a voiceover saying, “After six weeks of constant gut issues, I tried Fierce Immunity and in just two days, my discomfort vanished.”

In Rebel Lion webinars on YouTube, the commentary about Fierce Immunity gets even wilder. In a webinar dedicated to the “Real Story Behind the Measles Outbreak,” Rebel Lion co-founder Chris Roy said that “nobody that I know that’s taking Fierce Immunity is getting sick.” Roy also claimed that his friend’s sister “had breast cancer — stage four — and started taking Fierce Immunity and within about a month they said her tumors are shrinking.”

Fierce Immunity is being sold by a company led by medical misinformers

According to Rebel Lion's website, Fierce Immunity was “founded by Mikki Willis, Chris Roy, and JP Sears.” Willis and Sears both have histories of spreading medical misinformation.

Willis is the creator of the viral film Plandemic, which Wired reported was a “widely debunked pseudo-documentary” that “suggested Covid-19 was released to profit those in positions of authority and that vaccines were ineffectual.” During Rebel Lion's “The Real Story Behind the Measles Outbreak” webinar, he falsely claimed that measles is a “bioweapon” that has “been manipulated and targeted towards a community that is a threat because of their natural way of living.” In February, Willis also claimed that he had “been working with RFK Jr.” and Director of National Intelligence Tulsi Gabbard “for over a decade.”

Willis is still sowing doubt and mistrust around the safety of COVID-19 vaccines. During the Rebel Lion webinar, Willis encouraged viewers to share an upcoming video with their friends and family who still trust vaccines and linked his father’s heart issues to vaccines:

In the description of the “ Real Story Behind the Measles Outbreak” webinar, Rebel Lion describes the video as an “urgent discussion … unpacking the latest measles outbreak in Texas and exposing what mainstream media refuses to report,” including questions like “Is this a mutated bioweapon?” and “Are vaccinated individuals more vulnerable?”

Journalists have described Sears as a “conservative, anti-vaccine comic” and “the clown prince of wellness.” In his comedy sketches, Sears has implied that vaccines cause autism, that COVID-19 boosters are intended to depopulate the world, and that mRNA vaccines are ineffective.

Roy, who owns the “Rebel Lion” trademark, doesn’t seem to have a significant history as a public persona online. Instead, he seems to bring the marketing expertise to the Rebel Lion project.

In May, Rebel Lion released a film that featured Dr. Ben Edwards and Dr. Richard Bartlett, who have downplayed the threat of measles, and Pierre Kory, whose certification was revoked by the American Board of Internal Medicine for his promotion of ivermectin as a treatment for COVID-19.

Edwards reportedly treated measles patients in Texas, including children, with cod liver oil while reportedly having an active measles infection himself.

Bartlett has suggested that the measles vaccine could cause measles and that reporting on the rise in measles is a “misinformation, disinformation campaign to character-assassinate RFK and the Make America Healthy Again movement.” During the “Real Story Behind the Measles Outbreak” webinar, Willis asked Bartlett: “Should we stop all measles vaccines and let children get natural immunity?” Bartlett didn’t seem to answer the answer directly, but he said: “Parents deserve to know all the information. … We’re supposed to as doctors give informed consent. As far as vaccines, it’s again an individual decision. Traditional vaccines made with a live virus or a live weakened virus make sense to me. But there’s a risk. They’re live measles viruses. Live measles viruses cause measles.” He added that “every risk of measles can happen with the MR vaccine. And you’re not gonna hear that on CNN.”

During the May film, Kory argued that “measles is essentially just a rash. It was one of the most common childhood illnesses. It’s not lethal by any stretch of the imagination. Over 90% of kids with measles will suffer no complications. And the few that do, those complications are easily treatable.”

The Centers for Disease Control has been clear: Measles “isn't just a little rash.” In fact, the CDC says that 1 in 5 people who get measles will be hospitalized, and 1 in 20 children with measles will get pneumonia, which is “the most common cause of death from measles in young children.” A 2024 study also estimated that measles vaccines averted over 60 million deaths between 2000 and 2023.

Medical misinformers often sow doubt around vaccines and then profit from anxious consumers

Fierce Immunity offers something of a window into a larger industry in which grifters profit off fear and medical misinformation, seeding distrust in lifesaving vaccines while simultaneously selling bogus solutions.

Immediately after stoking fear about COVID-19 vaccines in the Rebel Lion webinar, Willis said, “This is why we created Fierce Immunity.” Roy added that when measles started breaking out, “that was the beginning of the conversation — was we were getting so many people asking us what they should do, what they should take, how should they build their immune system. Because we know … it all starts with the immune system.”

This sort of approach is also seen elsewhere in the medical misinformation space. For instance, a 2024 study from the University of Washington documented how wellness influencers leveraged anti-vaccine messaging for profit, using it to sell products including heavy metal detox sprays and supplements, homeschooling resources, and “off-grid” supplies. And during the pandemic, right-wing media figures and anti-vaccine activists peddled ivermectin as a miracle drug, even though it is ineffective at treating COVID-19.

Rebel Lion’s “Measles Protocol” also includes Budesonide, which the American Academy of Pediatrics has said is “not a recommended nor effective treatment for measles,” and an “antimicrobial oral rinse that reduces viral and bacterial load in the mouth.”