Fighting the Battle Against Health Misinformation Online

On social media, health-related misinformation proliferates with alarming speed and persistence. Recent years have seen wild claims circulate widely—from assertions that ginger is “10,000 times more effective” than chemotherapy at fighting cancer to allegations that fluoridated water provides “no benefits, only risks” and that measles vaccines are more dangerous than the disease itself.

The impact of such misinformation extends beyond mere confusion. According to a national survey released in January by Abacus Data and the Canadian Medical Association (CMA), false health claims directly affect patient care. After encountering health misinformation, 35 percent of respondents delayed seeking appropriate medical attention, while 29 percent avoided effective treatments altogether.

For health experts attempting to counter these false narratives, the challenge seems insurmountable. With millions of social media posts published daily, how can they identify which misleading claims will gain traction and determine effective counterstrategies?

Researchers at the University of Waterloo in Ontario have developed a potential solution: a tool called U-MAS (UbiLab Misinformation Analysis System) designed to track health misinformation patterns before they escalate into public health crises. Launched in 2022 and still under development, U-MAS has already been used to analyze false claims about the Russia-Ukraine conflict and is currently focused on vaccine hesitancy and misinformation related to fluoride, heatwaves, and diet.

The scale of the problem is significant. A 2022 World Health Organization study found misinformation in approximately 60 percent of social media posts related to pandemics (with 29 percent specifically about COVID-19) and more than 50 percent of posts about vaccines across platforms like X (formerly Twitter) and Instagram.

Beyond simply monitoring viral posts, U-MAS can identify overlooked factors fueling misinformation spread. For instance, their research on vaccine hesitancy during the COVID-19 pandemic revealed that while concerns about vaccinating children received much attention, worries about vaccine safety for seniors were also prevalent—potentially leading some adults to discourage their parents from getting vaccinated.

Currently, access to U-MAS is limited to Waterloo researchers and their institutional colleagues, but the development team—Zakir Hussain, Dr. Jasleen Kaur, and Professor Plinio P. Morita—aims to make it more widely available.

In one revealing 2022 study, U-MAS examined 500 Instagram posts containing the term “fluoride-free,” a hashtag commonly used by those opposing water fluoridation. While many posts framed fluoride avoidance as part of a healthy lifestyle, the analysis revealed that politically-charged messages—representing just 16 percent of posts—spread more widely. Posts generating high engagement often suggested governments were deliberately concealing dangerous side effects.

The researchers also found that anti-fluoride messaging increased significantly during the COVID-19 pandemic, coinciding with a rise in government conspiracy theories.

This is particularly concerning because community water fluoridation has strong scientific backing, with endorsements from the World Health Organization, Canadian Dental Association, and Public Health Agency of Canada. U.S. Centers for Disease Control studies show fluoridated drinking water reduces tooth decay by approximately 25 percent among both children and adults.

Despite this evidence, more than a dozen Canadian communities have discontinued water fluoridation programs since 2017, partly due to unsubstantiated health concerns. Scientific consensus indicates that the primary documented risk in Canada involves mild dental fluorosis—a cosmetic issue caused by excessive fluoride exposure during tooth development.

“If [misinformation is] shared and becomes an infodemic, that becomes a very bad public health outcome,” warns Irfhana Zakir Hussain, PhD student and core developer of the U-MAS project.

The real-world consequences were illustrated in Richmond, Vermont, where a water department official admitted to secretly reducing fluoride levels in local water supplies based on personal concerns about Chinese-sourced fluoride and skepticism about recommended fluoridation levels. This action sparked community concerns about children’s dental health and government transparency.

Dr. Joss Reimer, CMA’s current president and former medical lead for Manitoba’s COVID-19 Vaccine Implementation Taskforce, emphasizes that misinformation can be deadly: “During the pandemic, I saw first-hand how misinformation becomes literally a life-or-death issue. In Manitoba, there were people struggling to breathe, but still denying COVID was real.”

A Council of Canadian Academies report suggests that belief in COVID-19 as a “hoax” contributed to more than 2,800 deaths in 2021. COVID-19 misinformation also led millions of Canadians to delay vaccination.

“We had pregnant patients who believed the lies about the vaccine, got sick and gave birth prematurely, leading to lifelong health problems for those infants,” Reimer notes.

Timothy Caulfield, a Canada Research Chair on health law and policy, sees U-MAS as part of a growing international effort to combat health misinformation. “In the past, some experts may have ignored false claims, assuming that science-based information would prevail, but now there’s growing recognition that action is required.”

Healthcare providers have a crucial role to play. The CMA survey found that physicians remain the most trusted source of health information for Canadians, followed closely by nurses and pharmacists.

Comprehensive strategies for addressing misinformation include regulatory interventions, educational curriculum emphasizing critical thinking, and “pre-bunking” messaging that anticipates and addresses health concerns before they become widespread. Tools like U-MAS can inform these approaches by identifying which false narratives are most likely to gain traction.

“Tools like this that take a big-data approach are desperately needed,” says Caulfield. “They’re helping build resilience against misinformation.”