Nearly 50% in US Believe in Medical Conspiracy Theories
Get the world’s most fascinating discoveries delivered straight to your inbox.
You are now subscribed
Your newsletter sign-up was successful
Want to add more newsletters?
Delivered Daily
Daily Newsletter
Sign up for the latest discoveries, groundbreaking research and fascinating breakthroughs that impact you and the wider world direct to your inbox.
Once a week
Life's Little Mysteries
Feed your curiosity with an exclusive mystery every week, solved with science and delivered direct to your inbox before it's seen anywhere else.
Once a week
How It Works
Sign up to our free science & technology newsletter for your weekly fix of fascinating articles, quick quizzes, amazing images, and more
Delivered daily
Space.com Newsletter
Breaking space news, the latest updates on rocket launches, skywatching events and more!
Once a month
Watch This Space
Sign up to our monthly entertainment newsletter to keep up with all our coverage of the latest sci-fi and space movies, tv shows, games and books.
Once a week
Night Sky This Week
Discover this week's must-see night sky events, moon phases, and stunning astrophotos. Sign up for our skywatching newsletter and explore the universe with us!
Join the club
Get full access to premium articles, exclusive features and a growing list of member rewards.
About half of Americans agree with at least one medical conspiracy theory, a new study suggests.
The study surveyed more than 1,300 Americans to see whether they agreed with six popular medical conspiracy theories — such as the discredited link between vaccines and autism, or the belief that water fluoridation is a cover-up to allow companies to dump dangerous chemicals into the environment.
Nearly half, or 49 percent, of those surveyed agreed with at least one medical conspiracy theory, and 18 percent agreed with three or more theories. [Top Ten Conspiracy Theories]
The most commonly endorsed theory was the belief that the Food and Drug Administration is "deliberately preventing the public from getting natural cures for cancer and other diseases because of pressure from drug companies." More than a third of Americans, or 37 percent, agreed with this statement.
Twenty percent agreed with the statement: "Health officials know that cell phones cause cancer but are doing nothing to stop it because large corporations won’t let them." The vaccine-autism link was supported by 20 percent of participants.
Study researcher Eric Oliver, a professor of political science at the University of Chicago, said he was not surprised by the findings. Studies of American's belief in political conspiracy theorieshave yielded similar results.
"We see that Americans have conspiracy theories about a lot of things, not just about politics, but also about health and medicine as well," Oliver said.
Get the world’s most fascinating discoveries delivered straight to your inbox.
Why we believe
Belief in conspiracy theories is not necessarily a sign of a psychological condition such as paranoia, Oliver said. Rather, in cases of uncertainty, people have a natural tendency to assume that malevolent forces are behind the "unknown," Oliver said.
"These narratives seem like very compelling explanations for complicated situations," Oliver said.
Humans may have evolved to think this way, Oliver said. "If you hear a noise in the bush, it's much more adaptive to believe that there's a predator there than not," he said.
Public health implications
However, this widespread belief in medical conspiracy theories may have implications for pubic health.
Participants who supported medical conspiracy theories were less likely to get flu shotsand use sunscreen, and more likely to say they got health information from celebrity doctors, than those who did not endorse these theories.
Doctors should be aware that patients who endorse medical conspiracy theories may be reluctant to follow medical advice or comply with medical treatments, Oliver said.
Oliver suspects that overturning such beliefs would be difficult.
"People are attaching themselves to these narratives for psychological reasons, these narratives are providing them with feelings of certainty," Oliver said.
Oliver noted that science embraces a lot of uncertainty, which may not be intuitive to some people. But improving education, particularly about science and medicine, may help people better understand scientific information, he said.
The study is published in the March 17 issue of the journal JAMA Internal Medicine.
Follow Rachael Rettner @RachaelRettner. Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.
