Measles, mumps and misinformation: how Crunchy Moms became ‘the most dangerous group’ on Facebook | Meta

ADuring a measles outbreak that swept through Lancaster County, Pennsylvania, in August, a parent turned to a large public Facebook group, Crunchy Moms, for advice. They were considering vaccinating their three-year-old, in part to protect their six-month-old.

“I’m nervous for my baby,” the parent wrote.

“First of all, your children can’t die of measles. It’s literally impossible,” one member responded. “Don’t do it,” advised another. Others said the vaccine would spread measles or that it would be like “injecting yourself with poison.”

At the end of the post, Facebook’s AI system – run by its parent company Meta – summarized the 589 responses, writing in part that commenters “claim the vaccine is useless or even harmful.”

None of these statements are true. Pennsylvania has reported six deaths associated with measles this year, including two babies in Lancaster County. The measles, mumps, and rubella (MMR) vaccine is safe and effective. Health officials say it’s the best defense against measles spreading and injuring or killing people.

Scientists, doctors and child health and safety advocates told the Guardian that what they are seeing at Crunchy Moms and similar groups is alarming. They fear children will be harmed and mothers will be drawn into an online community that rejects science and evidence-based medicine. A scientist who spends her free time monitoring the platform for health misinformation calls Crunchy Moms “the most dangerous group on Facebook.”

Meta has not commented on this characterization.

The spread of misinformation on Facebook has been a problem for years, but in the past the company has taken steps to stop it. During the Covid-19 pandemic, for example, Facebook recognized that it had a problem and changed its policies to “prioritize connecting people with accurate health information.”

But last year, shortly before Donald Trump’s inauguration, Mark Zuckerberg, the billionaire founder of Facebook, declared that there was “too much censorship” on Meta’s platforms.

Meta changed course; it eliminated fact-checkers in the United States and reduced active moderation of anything other than the most serious or illegal content. The company still maintains a policy that prohibits misinformation that is harmful to health, but it is unclear how Meta enforces it and how its new permissive approach affects users at a time when measles and other infectious diseases are making a comeback.

In response to questions from the Guardian, Meta said nothing had changed in the policy or the way it was implemented since 2023.

A The Guardian investigation found that dangerous medical misinformation is circulating freely on Facebook in groups like Crunchy Moms, which now have more than 490,000 members. Additionally, the company appears to have helped spread such ideas by promoting Crunchy Moms in users’ feeds, even when they aren’t searching for it.

Zuckerberg previously suggested that waiting for users to report “bad things” — rather than letting automated systems detect them — would strike a better balance between what he calls censorship and free speech.. But the Guardian found that following the approach suggested by Zuckerberg appears to have little or no discernible effect on the misinformation circulating on Crunchy Moms.

Facebook took no action on more than 50 posts and comments, a Guardian journalist reported to the platform from her own Facebook account. The messages appear to violate Meta’s own standards, including that vaccines cause autism, that measles is not fatal, or that “miracle cures” like the caustic agent black balm that destroys skin tissue can treat cancer. Facebook has not acknowledged or responded to any of the Guardian’s reports, published in May, July and September.

In response, Meta said its misinformation policies allow people to discuss their personal experiences and scientific research. It said it removes misinformation when it is likely to directly contribute to the risk of imminent physical harm. But Meta did not respond to detailed questions about Crunchy Moms or to experts’ assessment that such misinformation is commonplace in the group.

Meta’s turnover exceeded $200 billion last year.

Doctors, researchers, former employees and public health advocates said the Guardian’s findings show Meta’s pendulum has swung back to a time when there was little moderation of false health information.

“We documented that Facebook recommended anti-vaccine groups to parents almost a decade ago,” said Renée DiResta, a professor at Georgetown University who studies online manipulation.

She and others showed how this approach harmed children. At the time, there were stories of children being injured or dying after their parents turned to Facebook groups for health advice.

“I’m afraid we’re going to see the same kind of dynamic again.”

Facebook recommendation triggers Guardian investigation

A Guardian journalist was scrolling through her phone in March when something caught her eye. Her Facebook feed recommended she join a group called Crunchy Moms: Natural Living & Clean Products.

The group was created in March 2025, less than three months after Zuckerberg announced Meta’s new hands-off approach.

Crunchy Moms administrators describe it as “a supportive space for moms who want to raise their families using toxin-free products, low-toxic alternatives, and clean ingredient solutions.” But a quick check of the group revealed, and experts confirmed, that it was a hotbed of medical misinformation that could harm people — especially children and their mothers, who look to the group for community, advice and affirmation.

The group focuses largely on health, although some posters also come seeking parenting advice, product recommendations and other non-medical questions. Many posters seem to take it for granted that group members are – or should be – against vaccinating their children. They frequently describe vaccines and their ingredients as deadly, toxic, or poisonous.

“We don’t vaccinate in this group. It’s the basis for becoming a crisp mom,” an anonymous member explained last month, in response to a question about the vaccine against RSV, a respiratory virus. A group admin responded to another post: “As a vibrant community we are generally against v@cs” – code for vaccines.

Crunchy Moms has more than doubled in size since January and receives hundreds of posts per day, as well as thousands of comments and replies.

Sara Rupe launched the group in March 2025. This was less than three months after Zuckerberg announced Meta’s new hands-off approach. The Connecticut mom said in an interview that her intention in starting the group was to share product recommendations for things like personal care products and makeup, but it turned into something bigger.

At least part of Crunchy Moms’ success, she said, is that it doesn’t block “free speech.”

“Everyone has the right to say whatever they want as long as it meets Facebook’s community standards,” Rupe said. “I don’t censor things.»

Rupe added: “If someone wants to say something, then I usually let it. But I mean, within reason, if I really think it’s going to hurt someone, I don’t do it. But I also think letting some information out could be a good thing.”

Crunchy Moms is the largest group in a network of groups that collectively has over a million members. Rupe runs them with the help of several administrators and moderators, including her husband, who is a registered nurse, a pastor and wife couple in upstate New York, and a woman whose Meta-verified account describes her as a doctor of holistic health.

They often post links to supplements and other products for sale on an Amazon store, with links to another admin’s skin care line, or with affiliate links to products that offer a cut of sales to the person sharing them.

Rupe said she and another administrator use multiple accounts to manage the group, which allows them to access it if Facebook restricts her account. Her daughter was in seventh grade last year when Rupe used her account to post a list of more than three dozen products, including bundles of herbal remedies that cost more than $100, fluoride-free toothpaste, a $25 tallow balm and red light therapy panels that cost $200 or more.

A second administrator, Dawn Mannion, said she makes no money from the group, although others receive a small commission that “isn’t even minimum wage.” She said she frequently recommends that members see a holistic doctor or other qualified health professionals. She added: “We don’t discourage people from seeking medical care. We encourage it.”

Other administrators and moderators contacted by the Guardian did not respond to Facebook messages and texts seeking comment.

Many Crunchy Moms members were already fans of the “natural lifestyle” and questioning vaccines when they joined the group, and group leaders don’t try to influence anyone’s mind, Rupe said.

Rupe has an autistic child who she says is now linked to vaccination, and said many others in the group believe their children were harmed by vaccines.

“We don’t want anyone to get hurt,” she said. “We want everyone to be as happy and healthy as possible. »

While Crunchy Mom posters often vehemently advise against vaccines and modern medicine, Rupe said she doesn’t think the group is harming anyone. Instead, she said it helps people make their own decisions.

Some members say vaccines are so dangerous that it’s…