Just a few social media posts from self-styled ‘experts’ can strongly influence opinion, study says

Social Media Posts Influence Public Opinion, Study Reveals

Rapid Shift in Beliefs via Limited Exposure

Just a few social media posts - A new study demonstrates how just a few social media posts from self-proclaimed experts can significantly shape public opinion. Researchers from Trinity Business School and NEOMA Business School analyzed how minimal exposure to content—often just three to five posts—can lead to the formation of strong, persistent views on unfamiliar topics. The findings, published in May 2026, show that repeated exposure to similar messages, even from non-experts, can create a sense of credibility in users. This was tested using simulated Instagram-style content on news topics, with participants from the United States forming opinions without prior knowledge.

The Power of Perceived Authority

The study underscores how trust in a source can be built quickly, even when that source lacks formal qualifications. Professor Ashish Kumar Jha, one of the lead researchers, explained to Euronews’ fact-checking team,

"We found that the most trusted sources are often celebrity experts, like a doctor who is also a White House advisor. Their millions of followers make their messages more influential, even if their expertise is questionable."

While celebrities rank second in trust, individuals with professional titles such as "Dr." are also highly regarded. However, Kumar Jha noted that the ease of claiming such titles online means anyone can assert authority, making just a few social media posts a potent tool for shaping perceptions.

Pandemic as a Real-World Test Case

The researchers used the early stages of the COVID-19 pandemic to illustrate the phenomenon. In January and February 2020, public knowledge about vaccines was limited, yet by March, millions of people had developed firm stances on the issue. Kumar Jha observed,

"During the pandemic, people formed strong beliefs about vaccinations after seeing just a few posts. These views often overshadowed more nuanced information, creating a feedback loop of influence."

This rapid shift highlights how social media can amplify opinions before evidence is fully established, demonstrating the power of just a few social media posts in driving collective sentiment.

Cognitive Biases in Social Media Influence

The study explores the psychological mechanisms behind this behavior. It found that early opinions are often formed through mental shortcuts, such as familiarity and coherence, rather than thorough analysis. Participants retained their initial views for days, indicating that once an opinion is formed, it becomes resistant to change. Kumar Jha added,

"The threshold for believing one is an expert is low. This leads people to share information aggressively, even when it contradicts established facts."

The research suggests that individuals may interpret new information as a challenge to their identity, reinforcing their beliefs through just a few social media posts.

Impact on Information Sharing Dynamics

Once users adopt the belief that they are experts, they are more likely to view opposing views as attacks on their credibility. Kumar Jha explained,

"People start defending their beliefs strongly when they perceive themselves as knowledgeable, even if the information they share is misinterpreted or incorrect."

This dynamic can accelerate the spread of misinformation, as individuals are less inclined to question their own conclusions. The study also noted that content aligning with preexisting views is shared more frequently, creating echo chambers that are fueled by just a few social media posts.

Changing Landscape of News Consumption

The research highlights a growing trend in how people access information. As traditional news platforms lose relevance, social media and video networks are increasingly becoming the primary sources of news. A 2026 Reuters Digital News Report confirmed this shift, stating that for the first time, social media and video platforms became the most widely used method for consuming online news globally. This change, once localized, now affects international audiences, raising concerns about the reliability of information sources shaped by just a few social media posts.

Implications for Media and Society

Kumar Jha emphasized the importance of understanding this trend for media organizations and policymakers. The study’s findings suggest that public discourse is increasingly influenced by content from non-traditional experts, who can sway opinions with minimal effort. This has implications for how information is verified and how misinformation spreads. As social media continues to dominate news consumption, the role of just a few social media posts in shaping public perception becomes more critical than ever. The research calls for greater awareness of how online influence can override traditional fact-checking processes.