Fact check: What are the consequences of spreading misinformation and conspiracy theories on social media?

Executive summary — Misinformation on social media produces measurable harms to health, social trust, and democratic information ecosystems. Multiple recent studies and reporting link exposure to false or conspiratorial content with increased mental-health burdens, heightened ideological polarization, tangible public-health harms (reduced vaccine uptake, extra cases and deaths), and rising challenges for fact-checkers as platforms change policies. The pattern across these sources shows consistent adverse outcomes and systemic risks, while also revealing contested remedies and differing accounts of responsibility among platforms, researchers, and civil-society actors ^{[1] [2] [3] [4] [5]}.

1. Shocking personal consequences: when beliefs cost lives and health outcomes grab headlines

Reporting documents cases where conspiracy-driven choices had fatal outcomes, such as a young woman rejecting chemotherapy after exposure to alternative-treatment claims, illustrating direct, individual-level harm from misinformation. Journalistic and clinical observers link these examples to broader patterns: parents influenced by conspiracies denying vaccinations and treatments for children, resulting in preventable deaths and severe illness. These accounts emphasize that misinformation does not remain abstract; it can alter medical choices with lethal consequences. The reporting frames this as an urgent call for improved digital literacy and protective policy interventions ^[4].

2. Mental health effects: empirical links between fake news and anxiety or depression

A 2025 study of Vietnamese adolescents and young adults found that frequent exposure to fake news and problematic social-network use correlated with higher PHQ-9 and GAD-7 scores, indicating greater depression and anxiety and an increased propensity to share misinformation. The research draws a chain from heavy social-media consumption to poorer mental-health outcomes and reciprocal amplification of false content. This evidence frames misinformation as not only a public-information problem but also a public-mental-health issue requiring targeted interventions like coping-skills training and moderation of platform features ^[1].

3. Population-level public-health impacts: antivaccine messaging translated into cases and deaths

A study estimating the effects of antivaccine tweets on COVID-19 outcomes reported that exposure to antivaccine content reduced vaccine uptake by an estimated 14,086 people, which the authors linked to at least 510 additional cases and 8 extra deaths during a specific 2021 period. This research supplies a causal-sounding, quantitative bridge from online messaging to measurable epidemiological outcomes, reinforcing that disinformation can impose tangible costs on public health systems and population mortality, not solely on opinions or beliefs ^[3].

4. Platform dynamics: algorithmic changes and rising ideological polarization

Analysis of over six million news-related URLs shared on Facebook from 2017–2020 identified an upward trend in ideological polarization and the spread of biased or false stories coinciding with algorithmic changes. This suggests platform-level affordances—ranking, recommendation, and distribution mechanics—can amplify polarizing and low-credibility content. The finding reframes responsibility from isolated users to structural incentives built into social-media ecosystems, implying that policy or algorithmic redesigns could materially shift the information environment ^[2].

5. Fact-checking under pressure: withdrawal of platform support and debates over fairness

Recent reporting documents a retrenchment in platform-supported fact-checking and a growing strain on professional fact-checkers, who face reduced reach as platforms alter collaborations. Observers warn this could worsen misinformation effects around critical events like elections. At the same time, scholarship highlights concerns about bias and Western media dominance in fact-checking, arguing that credibility rests on diverse, transparent methods and stronger local partnerships to avoid inadvertently silencing or delegitimizing non-Western perspectives ^{[5] [6] [7]}.

6. Competing remedies and contested agendas: education, platform rules, and civic enforcement

Across sources, proposed remedies range from expanded digital-literacy curricula and mental-health supports to platform algorithm changes and more robust, transparent fact-checking regimes. Stakeholders advance different priorities—platforms emphasize user tools and community standards, academics stress structural analysis and measurement, while journalists and public-health officials press for immediate moderation of harmful content. These divergent emphases reflect distinct institutional incentives and agendas: mitigation strategies will therefore vary depending on whether the aim is individual resilience, system redesign, or regulatory enforcement ^{[1] [5] [6]}.

7. What the evidence converges on — risks are real, multifaceted, and solvable but politically complex

The corpus of studies and reporting from 2024–2025 consistently indicates that misinformation produces multidimensional harms—psychological distress, increased polarization, fewer vaccinations, cases and deaths, and erosion of trust in information institutions. While the research supports targeted interventions, it also exposes trade-offs and governance gaps: platform policy shifts can help or hurt, fact-checking faces resourcing and credibility dilemmas, and educational measures take time. Policymakers should weigh immediate mitigation against long-term resilience, grounded in transparent metrics and diverse, locally rooted fact-checking partnerships ^{[1] [3] [7]}.