Fake news kills people, splits communities, and erodes the shared trust that societies need to function. Those aren’t hypothetical risks. During just the first three months of 2020, misinformation about COVID-19 led to roughly 6,000 hospitalizations and 800 deaths worldwide, largely from people acting on false medical advice they encountered online. The damage extends well beyond pandemics, touching everything from vaccination rates to political stability to personal safety.
How Misinformation Costs Lives
The most direct harm from fake news is medical. When false health claims spread widely enough, people make dangerous decisions with their bodies. By June 2020, 15 people in the United States alone had consumed disinfectant products in the belief it would prevent COVID-19 infection. Four people died from methanol poisoning tied to similar misinformation, and three others were left with permanent vision loss.
These aren’t isolated incidents of individual poor judgment. They’re the predictable result of bad information reaching millions of people simultaneously. Misinformation during the pandemic fueled vaccine avoidance, mask refusal, and the use of medications with no meaningful scientific backing. Each of those behaviors, multiplied across populations, contributed to preventable illness and death on a massive scale.
Vaccination Rates Drop With Exposure
One of the clearest, most measurable harms of fake news is its effect on vaccination. A survey published in the Journal of General Internal Medicine found that 73% of participants had been exposed to at least some COVID-19 vaccine misinformation in the previous six months. Among those who reported no exposure to misinformation, nearly 74% were vaccinated. That number dropped to about 63% with exposure to just one false narrative and fell to 52% among people exposed to six or more misinformation themes.
Certain conspiracy claims hit even harder. People exposed to the false story that COVID-19 was created to boost vaccine sales, or that the Russian president’s daughter died from a vaccine, showed vaccination rates roughly 20% lower than those who hadn’t encountered those claims. Broader studies found a 6-point decline in vaccination rates linked to misinformation exposure in both the U.S. and the U.K. Those percentage points translate directly into unprotected people during a pandemic, which translates into hospitalizations and deaths.
Why Your Brain Falls for Repetition
Fake news exploits a well-documented quirk of human cognition called the illusory truth effect: the more often you encounter a claim, the more believable it feels. This isn’t a matter of intelligence or education. Repetition increases belief even in claims that are implausible or directly contradict what someone already knows. Your brain processes familiar information more fluently, and that fluency gets misread as accuracy.
This is what makes social media such a potent vehicle for misinformation. A false headline shared thousands of times doesn’t just reach more eyes. It becomes more convincing to each person who sees it for the second, third, or tenth time. The platforms’ algorithms, designed to surface engaging content, naturally amplify emotionally charged falsehoods because those generate clicks and shares. The result is a feedback loop where the most outrageous claims gain the most repetition and, counterintuitively, the most perceived credibility.
Who Is Most Vulnerable
You might assume that older adults, who are often stereotyped as less digitally savvy, are the primary targets of health misinformation. The research tells a different story. A national survey-based analysis published in the Journal of Medical Internet Research found that younger adults between 18 and 34 showed the greatest vulnerability to health misinformation on social media. Every older age group was significantly less likely to use social media as a basis for health decisions. Adults 35 to 49 were about 45% less likely, and adults 75 and older were about 43% less likely, compared to the youngest group.
The explanation is straightforward: younger adults spend more time on social media, which means more exposure to misleading content that can factor into real health choices. Researchers noted that younger users showed a tendency toward superficial processing of information, making them more susceptible to persuasive content. Interestingly, education level did not emerge as a significant factor in any of the models examined. A college degree doesn’t reliably protect someone from believing false health claims encountered in a social media feed.
Physical Violence and Targeted Attacks
Fake news doesn’t just change beliefs. It changes behavior, sometimes violently. During the COVID-19 pandemic, more than 11,000 incidents of physical violence and online aggression against Asian communities were reported in the United States, driven in part by false narratives about the origins and spread of the virus. Misinformation framed as medical information also disproportionately targeted Black communities, compounding existing health disparities with an additional layer of distrust and harm.
These patterns aren’t unique to the pandemic. Researchers at Georgia Tech have documented a consistent connection between online misinformation campaigns and real-world property destruction, assaults, and targeted harassment. The mechanism is consistent: false narratives identify a scapegoat, social media amplifies the message until it feels like common knowledge, and some portion of the audience acts on what they believe to be justified anger.
Eroding Trust in Everything
Perhaps the most insidious harm of fake news is what it does to trust itself. According to Pew Research Center, only 56% of U.S. adults now have at least some trust in information from national news organizations, a drop of 20 percentage points since 2016. Local news fares better at 70%, but that figure has also fallen from 82% over the same period.
The generational picture is particularly striking. Adults under 30 are now roughly equally likely to trust information from national news organizations (51%) as they are to trust information from social media (50%). That near-parity represents a collapse of the credibility gap that once separated journalism from unvetted online content. When a verified news report carries no more weight than a viral post, the shared factual foundation that democratic debate depends on starts to crumble.
Trust in social media information itself is low across the political spectrum, with only 37% of both Republicans and Democrats saying they have at least some confidence in it. But low trust in everything is not the same as healthy skepticism. It creates an environment where people retreat to information sources that confirm existing beliefs, because nothing feels reliably neutral.
Deepening Political Division
Research published in Frontiers in Information Systems confirms what many people sense intuitively: disinformation plays a definitive role in polarizing societies along partisan lines. The study, which examined patterns across multiple countries, found that in highly polarized environments, disinformation and hate speech act as core drivers of division. In countries with low polarization, hate rhetoric was consistently absent.
The polarization isn’t just intellectual disagreement about policy. It carries a strong emotional component, where people don’t just disagree with the other side but actively distrust and dislike them. That kind of affective polarization erodes social cohesion and destabilizes political systems. Foreign governments have exploited this vulnerability, using social media to spread disinformation designed to undermine trust in institutions, shift attitudes about politicians, and widen existing divisions. When domestic political actors and foreign operations push disinformation simultaneously, the polarizing effect compounds.
The Scale of the Problem
The World Health Organization has a term for the current landscape: infodemic. It describes an environment where there is simply too much information, including false and misleading content, flowing through digital and physical channels simultaneously. The sheer volume makes it difficult for anyone to find reliable guidance when they need it most, particularly during health emergencies.
The WHO’s framework for managing infodemics focuses on four pillars: listening to community concerns, helping people understand risk, building resilience to misinformation, and empowering communities to take constructive action. That last point matters because the harm from fake news is not just about individual gullibility. It’s a systemic problem that requires systemic responses, from platform design changes to media literacy education to better public communication from health authorities.
What makes fake news so destructive is the way these harms compound. Misinformation reduces vaccination rates, which causes outbreaks, which generates fear, which creates fertile ground for more misinformation. Polarization reduces trust in institutions, which makes people more reliant on social media for information, which exposes them to more false content. Each layer of damage makes the next layer easier to inflict.