In a closed Facebook group, British woman Amanda Mary Jewell has for years been selling the chemical GcMAF, claiming it is a cure for cancer and autism. She has provided no medical support for this claim.

Jewell also sells expensive, unregulated treatments at her clinic in the tropical nation of Belize. She is not a UK-registered doctor.

Both services are advertised on Facebook, in closed groups inaccessible without invitation.

Other unproven so-called "cures" — like the bleach known as Miracle Mineral Solution — also flourish in closed Facebook groups.

Experts say these groups are a breeding ground for disinformation. In the realm of life-altering diseases, a switch from a proven medical treatment to an unproven one could have serious consequences.

When contacted by Business Insider, Facebook closed some of the groups in question. It has since announced a rethink of the closed group system.

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In a phone call to the self-described cancer researcher Amanda Jewell, a British woman who calls herself "Mary" describes how she is struggling to cope.

"My mother, she has stage three breast cancer. It's spread to her right. It's spread to her lymph nodes and they're giving her chemotherapy. It's so distressing," she says.

She describes her difficulties with her six-year-old son's behavior: a "non-verbal autistic child, very picky in his diet, very violent."

"I've got him acting out and doing what he's doing and I've got my poor mother who's so ill, she's vomiting, her hair is starting to fall out," she says.

In the call, "Mary" begs for an appointment, having arranged the call by joining Jewell's invite-only Facebook group, GcMAF Oracle. She hopes it can provide the cure she's desperately seeking.

The name refers to Jewell's core product — the substance GcMAF, the common name for GC protein-derived macrophage activating factor.

Jewell, to her select audience, claims that GcMAF is a breakthrough treatment for a raft of otherwise incurable conditions, including autism and late-stage cancer.

Mary is in fact an undercover campaigner against medical disinformation, and made the call to expose how bogus practitioners operate.

"If I really juggle things around, I could get your mum in in a week's time," says Jewell. "Mary" is delighted.

They discuss prices for the treatment, which could involve surgery at Jewell's clinic in Belize, central America, as well as doses of GcMAF. "We do an all-in price with everything included," she explains, quoting her $25,000.

The total, Jewell says, excludes the cost of travel. She offers to treat the autistic son for free.

Jewell describes herself as a "medical assistant instructor" on Facebook, but Business Insider has found no evidence that she has any scientific qualification, and she is not registered as a doctor with the British Medical Association, the relevant authority in her home country.

In Belize, health authorities told Business Insider that they had never been presented with evidence that she has medical qualifications.

Jewell admitted to the BBC in 2016 she is not a doctor, but said she had worked with medical professionals for 15 years.

What's more, medical authorities in countries including the UK and US say that GcMAF, which she promotes as a life-saving cure, is unproven and unlicensed.

The UK's Medicines and Healthcare products Regulatory Agency told Business Insider that GcMAF has never undergone the tests necessary to establish whether it is effective, or even safe for human use.

"We strongly advise people not to use unlicensed products such as GcMAF, which may pose a significant risk to health," said a spokesperson.

And in the US, authorities had a similar warning.

"In general, GcMAF treatments are not approved or licensed by the FDA for use in the U.S.," said Jeremy Kahn, a spokesman for the Food and Drugs Administration in the US.

A breeding ground?

A Business Insider investigation has found that Amanda Jewell is not alone in exploiting Facebook's system of invite-only private and secret groups to spread medical disinformation and questionable medicine to thousands of people.

Facebook removed Jewell's personal account and the GcMAF Oracle group for violating its rules after her activities were flagged by Business Insider.

Before the takedown, the group had more than 7,000 members, each of whom had requested to join.

Inside the groups — largely invisible to moderators and regulators — anyone can falsely portray themselves as a medical expert.

And if they gain influence there, they can spread misinformation and market lucrative "treatments" which are, at best, a waste of money and, at worst, could cause serious harm.

More than half of Facebook's 2.2 billion global users are members of groups, usually networks of friends, family or colleagues.

Some are public and open to all users. Others, like Jewell's, are private but can be found by searching Facebook. These require approval from a moderator to join.

A third category is invitation-only, and cannot be found by searches.

Amanda Mary Jewell has for several years sold and promoted GcMAF as a cancer cure, despite the substance being untested and potentially dangerous Healing Oracle, YouTube

Moderators like Jewell are supposed to help enforce Facebook's rules banning harmful behavior.

However, there is nothing to stop anyone from bypassing the site's rules, spreading conspiracies and misinformation, and selling illicit substances.

One of the members of the group was Emma Dalmayne, the campaigner who posed as "Mary" in the call to Jewell. Dalmayne works to expose medical disinformation, and shared her recording with Business Insider to raise awareness of the problem.

She told Business Insider that if people with life-threatening illnesses reject proven remedies, the results can be fatal. On secret Facebook groups, she said, people can be persuaded to turn to unproven treatments instead of proven ones.

"They are allowing people to turn their backs on proven treatments to go with quacks, and they are giving them a platform," Dalmayne said of Facebook. Her conclusion: "They are allowing people to die."

Jewell has not responded to Business Insider's attempts to contact her, via email, LinkedIn, a previous phone number, and various intermediaries.

When Business Insider called a number associated with Jewell, a woman picked up the phone claiming to be her sister. The woman, who declined to give a name, said Jewell was in Honduras. She did not answer any substantive questions about Jewell's activities.

Jewell did publish a response to the deactivation of her Facebook accounts. Writing on her website, she said that the closures were a reaction to the success of her treatments.

"These were all innocent people in need of help and advice, good people actively involved and interested in natural cures, with testimonies of thousands of people and how they have helped themselves by recovering from illnesses like cancer, autism and many other chronic conditions.

"No crimes were committed here. We are not discussing anything other than simply helping people. It would seem that one too many people were getting real benefit.

"And so 15 years of knowledge lost. As people are once again left to delve deeper and look harder for good information.

"Our reach was over 5 million people and the numbers were increasing. Clearly our good results were too good."

It is not clear on what basis Jewell claims GcMAF cured thousands of people, or that her group reached 5 million.

GcMAF warning

GcMAF is a type of protein found in the body that helps boost the immune system and fight infections. A fringe alternative medicine movement has attempted to promote it as something more.

For years — without the support of mainstream science — advocates have claimed that boosting the amount of GcMAF in the human body can help to fight off otherwise incurable illnesses, including cancer.

The UK's Medicines and Healthcare products Regulatory Agency told Business Insider that GcMAF has never undergone the tests necessary to establish whether it is effective, or even safe for human use.

"We strongly advise people not to use unlicensed products such as GcMAF, which may pose a significant risk to health," said a spokesperson.

Last year, British businessman David Noakes was jailed for 15 months for producing GcMAF at a site near Dover, England, for breaking laws prohibiting the production and sale of unlicensed medicine.

In a video posted on YouTube, Amanda Jewell holds up a bottle of GcMAF YouTube

In the US, authorities had a similar warning.

"Under FDA law and regulations, generally a company first must show that its drug product is safe and effective before it may be marketed. GcMAF treatments have not been subject to the rigorous approval process and manufacturing scrutiny required for FDA-approved products, and are therefore not being legally marketed," said Kahn, the FDA spokesman.

But though its sale as a pharmaceutical has never been found to be safe or effective, on Facebook there is a thriving network of groups like Jewell's openly promoting it.

$3,900 a month for an unproven cure

Screenshots of conversations in GcMAF Oracle group — shared with Business Insider by autism rights campaigner Fiona O'Leary — show how moderators in the group promoted and sold the substance.

In one conversation, Jewell recommends a three-month course of GCMAF to a woman whose mother has stage 4 kidney and lung cancer. She advocates buying 32 vials of the substance at a price of more than $350 per vial. Business Insider's calculations found the treatment would cost around $3,900 per month.

In another exchange, a man with cancer describes struggling to fundraise for his GcMAF treatment.

Although his language is not completely clear, the message appears to say that GcMAF with he injects under his skin (subcutaneous, or "sub q") costs him $150 per milliliter.

In this screenshot, a man describes fundraising to afford Jewell's GcMAF treatment Facebook

He describes gathering money from family and friends, as well as running a GoFundMe page, to afford the treatment. Business Insider confirmed that the GoFundMe exists.

"For years I've watched Amanda Mary Jewell prey on vulnerable children and adults. Facebook must work with the authorities, help prosecute charlatans and deliver justice to the families," O'Leary told Business Insider.

Drinking bleach, and an anti-vaxx echo chamber

Business Insider has found numerous other examples of unproven, and therefore potentially dangerous, substances being promoted as medicines in closed Facebook eco-systems.

Dalmayne, the campaigner — who really does have an autistic child — has also joined private groups devoted to promoting so-called Miracle Mineral Solution as a cure for autism.

The substance is in reality a form of toxic bleach banned by medical authorities worldwide. In March Business Insider reported that in the Facebook groups parents share disturbing pictures of the injuries to their autistic children caused by MMS, while others encourage them to keep administering it.

Alongside GcMAF, Jewell has promoted MMS in her group as a treatment for autism and malaria.

Renee DiResta, a Mozilla Fellow in Media, Misinformation, and Trust for 2019, told Business Insider that networks of private and secret Facebook groups are also promoting anti-vaccination conspiracies, fake cancer cures, and promoting the sale of medical exemptions for parents who don't want their children vaccinated.

Jennifer Grygiel, an assistant professor in communications at Syracuse University, told Business Insider by email that Facebook's failure to enforce its policies presented a threat to public health.

Facebook, they said, "has been encouraging the use of private groups as a way to offload content moderation responsibility, and accountability, to moderators within these groups."

"The company should do more to make sure that its platform is not being abused or threatening public health."

Facebook said it had removed groups promoting MMS, GcMAF, and anti-vaccination conspiracies uncovered as part of Business Insider's investigation.

A spokesman for the site said: "We do not allow the sale of non-medical or pharmaceutical drugs on Facebook, and we have taken down all the groups, user accounts and related pages flagged by Business Insider."

"We have recently tripled the size of our safety and security team to 30,000 to help us keep Facebook safe. We also urge people to use our tools to report anything they feel shouldn't be on Facebook."

A spokesperson referred Business Insider to the site's policies on anti-vaccination disinformation, which say that the site downranks anti-vaccination misinformation on its news feed, and rejects all paid anti-vaccination ads.

A rogue medical clinic, fueled by Facebook

As well as running the Facebook group, Jewell had a project more ambitious than promoting and remotely selling GcMAF.

After contacting and talking to Jewell on the site, some people were persuaded to pay tens of thousands of dollars more to visit her clinic.

In her phone call with "Mary" — the pseudonym Dalmayne used in her call — Jewell quoted $25,000 for treatment at the Belize clinic, which included surgery as well as GcMAF.

In her call with Dalmayne, Jewell claims that she would not profit from the course.

"Not everything's financial," she said. "We all have to get something out of it, and for me it's what I get out of the job itself which is wonderful."

Jewell's clinic was for several years located in the village of Progresso in northern Belize. It was called the Flower of Health and Wellbeing Center.

Though the clinic was presented as place where life-saving treatments were available, it was never registered with medical authorities in Belize.

Jewell advertised her clinic in Belize with pictures with YouTube videos and through her Facebook group Healing Oracle/YouTube

At the clinic, Jewell personally administered courses of GcMAF.

On her YouTube channel, people who went to the center are interviewed about its benefits. In others films, Jewell provides advice on diet and cancer, and the "link between emotion and cancer."

In photos on her Facebook page, Jewell is pictured in an operating theater apparently in scrubs while a patient is undergoing a surgical procedure.

She told Dalmayne in her call that she does not operate on patients, but is instead present to reassure them. It is unclear who the people are who did operate on patients, and whether they had any qualification.

Dr Marvin Manzanero, Director of Health Services at the Ministry of Health in Belize, told Business Insider that his officials investigated and "didn't find any evidence of any surgery having been done there."

Manzanero said that Jewell closed down the clinic earlier this year, after authorities in Belize launched started looking into it.

"The clinic was never officially sanctioned by the Ministry of Health and so we only interviewed her once and she was told what our problem was with her ads and clinic, and she said she was leaving," he wrote.

"A follow-up visit two days later confirmed that she had basically left overnight."

A problem that's getting worse

DiResta, the disinformation expert, has spent five years monitoring the spread of anti-vaccination conspiracies and other medical misinformation on Facebook.

She told Business Insider that most people find the groups by typing in common search terms, like "vaccine" or "cancer cure."

Once someone manages to gain access to a private group like Jewell's — accessible to search but requiring the permission of moderators to join — some are given access to totally secret groups, which are not publicly searchable.

Here, banned medicines are sold via instant messenger.

"Once you've been a member of the private group and they trust that you're not a secret infiltrator or anything, that's when they refer you and invite you into the secret group — you see people being brought in more into more closed communities," she said.

"Most of these groups for anti-vaccination and cancer quackery will move people into these chats and develop a closer relationship before they deliver the contraband."

In Jewell's group, moderators will direct members not to discuss treatment delivery in public threads, but ask them to use direct messenger instead. It is unclear whether any secret groups operated on the periphery of Jewell's closed one.

Just how many closed or secret groups are using Facebook to sell or promote fake medicines is hard to say, said DiResta, as Facebook has made only limited information public.

Facebook's response

Facebook has taken some steps in recent months to limit the spread of medical misinformation and the promotion of fake cures on the site — but critics say it is not doing nearly enough.

After removing Jewell's groups, a spokesperson told Business Insider "We do not allow the sale of non-medical or pharmaceutical drugs on Facebook, and we have taken down the group, the user's account and related pages."

DiResta said the site had blacklisted some terms associated with the anti-vaccination movement, meaning that the groups promoting the conspiracy were not showing up in search.

In April Facebook removed one group by a prominent exponent of MMS, the banned bleach, before removing others flagged to the site as part of Business Insider's investigation.

In August the site announced a change to its groups policy, saying that it would get rid of the option to make groups "secret." Private groups would remain.

But for DiResta, the change was merely cosmetic, as groups would still be able to be taken out of search by labelling themselves "private and hidden."

"I don't see what substantive impact this will have on any of the issues they've had with the feature itself," she remarked.

A Facebook spokesperson directed Business Insider to more policies.

The policies say that "like all parts of Facebook, people in these groups must adhere to our Community Standards, which lay out what is and isn't allowed on our service. When people break these rules, including in private groups, we take action.

"Every single piece of content in private groups can be reported to us. Where we see that someone is an administrator of multiple groups that are all engaged in activity that violates our policies or is illegal then we may shut down all of those groups on the basis of a single report."

Dalmayne said that when she first came across Jewell's name, she had herself been recently diagnosed with lung cancer. She warned that, so long as Facebook fails to act, quacks will continue to use the platform to exploit the desperate.

"She comes across as anyone's best friend," she said of Jewell.

"When I had cancer, and someone had said it's terminal and you're leaving your kids, I'd have tried anything. You don't want to leave your family. You don't want to leave your children."