The Dangerous Allure of Facebook’s “Crunchy Moms” Community

In August, as a measles outbreak swept through Lancaster County, Pennsylvania, a worried parent turned to a massive public Facebook group called “Crunchy Moms” for guidance. The parent was considering vaccinating their three-year-old child, partly to protect their six-month-old infant. “I’m nervous for my baby,” they wrote. The responses came swiftly and confidently—and dangerously. “First of all your children cannot die of measles. It is literally impossible,” one member insisted. “Do not do it,” advised another. Others claimed the vaccine would spread measles or compared it to “injecting poison.” When Facebook’s artificial intelligence system summarized the 589 responses, it noted that commenters “claim the vaccine is unnecessary or even harmful.” Every one of those claims is false. Pennsylvania has reported six measles-associated deaths this year, including two babies in Lancaster County. The MMR vaccine is safe, effective, and health officials consider it the best defense against a disease that continues to injure and kill.

The Crunchy Moms group, which now boasts more than 490,000 members, describes itself as “a supportive space for moms who want to raise their families using toxin-free products, low-tox alternatives, and clean ingredient solutions.” But a Guardian investigation has found that the group has become a breeding ground for dangerous medical misinformation that could seriously harm children and their mothers. Scientists, doctors, and health advocates who reviewed the group were alarmed by what they found. One scientist who spends her free time monitoring the platform to highlight harmful health misinformation called Crunchy Moms “the most dangerous group on Facebook.” The group grew out of a network of similar communities that collectively have over one million members. It receives hundreds of posts daily and thousands of comments, many of which spread false claims about vaccines causing autism and sudden infant death syndrome, despite Meta’s own policies explicitly prohibiting such content. New and expecting mothers frequently post seeking help and advice, only to be bombarded with comments telling them to reject science-backed health recommendations like the Vitamin K shot for newborns, which can prevent life-threatening brain bleeds.

This situation represents a dramatic shift in Facebook’s approach to misinformation. During the Covid-19 pandemic, the company recognized its role in spreading false health information and changed its policies to “prioritize connecting people with accurate health information.” Facebook even stopped recommending health groups altogether, explaining that “it’s crucial that people get their health information from authoritative sources.” But the landscape changed dramatically in January 2025, when Meta’s billionaire founder Mark Zuckerberg announced there was “too much censorship” on the company’s platforms. Meta eliminated factcheckers in the United States and dialed down active moderation of everything except the most severe or illegal content. Zuckerberg suggested that waiting for users to report “bad stuff” rather than having automated systems catch violations would strike a better balance between what he termed censorship and free expression. The company still maintains a policy that prohibits harmful health misinformation, but the Guardian’s investigation found that the approach Zuckerberg suggested appears to have little to no discernible effect on the false information circulating in Crunchy Moms.

The Guardian’s investigation tested Meta’s enforcement approach directly. A journalist reported more than 50 posts and comments from the group to Facebook that appeared to violate Meta’s own standards—including claims that vaccines cause autism, that measles is not deadly, and that the caustic agent black salve, which destroys skin tissue, can treat cancer. Facebook did not acknowledge or respond to a single one of these reports, made in May, July, and September. Nearly all the reported content remained online. Even more troubling, the investigation found that Facebook appears to be actively promoting the group to users who haven’t sought it out. The Guardian spoke to several people who encountered Crunchy Moms in their feeds as a result of Facebook’s curation choices. “It came across my feed, and I engaged,” said one member who joined about six months ago. “I did not seek it out.” Another mother of two young children said the group showed up in her feed for months—even though she wasn’t part of it and never searched for anything similar. This recommendation system is significant: Facebook’s own reports show that recommendations now represent 36 to 39 percent of what users see in their news feeds, while content from friends makes up only about 20 percent.

The group’s administrators defend its existence, saying they’re simply providing a space for free expression. Sara Rupe, who launched Crunchy Moms in March 2025—less than three months after Zuckerberg announced Meta’s new hands-off approach—said her intention was to share product recommendations for personal care items and makeup, but it grew into something much larger. “Everybody has a right to say what they want to say as long as it’s within community standards of Facebook,” Rupe said. “I don’t censor things.” She acknowledged that she believes many comments are from “trolls” trying to get the group in trouble, and that people are simply posting their opinions. Another administrator, Dawn Mannion, said she frequently recommends that members seek medical attention from holistic or other qualified healthcare professionals. “We do not discourage people from seeking medical care. We encourage it,” she said. But a pediatrician who reviewed the group at the Guardian’s request, Dr. Alok Patel, said the comments dismissing modern medicine and discouraging vaccines, vitamin K shots, and doctor visits are “outright misinformation and potentially dangerous.” He noted that social media companies should prioritize providing quality information over keeping people on their apps.

The consequences of this misinformation are not theoretical. Research has shown that health misinformation shared on Facebook can have a real-world impact on people’s decisions. Jennifer Allen, a professor at NYU Stern who worked at Facebook from 2016 to 2018, and her colleagues estimated that exposure to vaccine-skeptical content on the platform during the Covid-19 pandemic reduced people’s intention to get vaccinated. Without that exposure, they calculated that 5 million more Americans would have been vaccinated, potentially saving approximately 21,000 lives. The pattern echoes what happened in 2019, when anti-vaccine activists used Facebook to undermine public health in places like Samoa, where a measles outbreak killed 83 people, mostly children under age five. Facebook responded to public pressure then, but the company has since reversed course. Renée DiResta, a professor at Georgetown University who studies online manipulation, noted that Meta’s AI even adds comment summaries to some posts that conflict with good science. On a post about the Lancaster measles outbreak, Meta’s AI summarized the discussion as including claims that “the vaccine is unnecessary or even harmful” without clarifying that this was false. “It’s very easy for an AI to do that,” DiResta said, referring to AI systems adding context or corrections. “But it seems, again, that they’re choosing not to do that.” As one group member from Minnesota said, describing how Crunchy Moms kept appearing in her feed despite having no interest in it: “I did not seek it out.” But for many vulnerable parents seeking community and advice, the group has become a dangerous destination—one that Meta continues to recommend, even as measles and other infectious diseases make a troubling comeback.