Misinformation about health remains widespread and popular.
Half of Americans subscribe to medical conspiracy theories, with more than one-third of people thinking that the Food and Drug Administration is deliberately keeping natural cures for cancer off the market because of pressure from drug companies, a survey finds.
Twenty percent of people said that cellphones cause cancer and that large corporations are keeping health officials from doing anything about it. And another 20 percent think doctors and the government want to vaccinate children despite knowing that vaccines cause autism.
"One of the things that struck us is that people who embrace these beliefs are not less health conscious," says Eric Oliver, a professor of political science at the University of Chicago who led the study. "They're just less likely to embrace traditional medicine."
Oliver was studying political conspiracy theories when he realized that quite a few of them involved medical care, including vaccine avoidance and a vote rejecting water fluoridation in Portland, Ore.
So he asked people what they thought about six common medical conspiracy theories, including the ones about vaccines, cellphones and natural cancer cures. They were the theories most widely supported.
Three other theories were each supported by 12 percent of people surveyed. They were that the CIA deliberately infected African-Americans with HIV, that genetically modified foods are a conspiracy to reduce population worldwide and that companies use water fluoridation to cover up pollution.
And though the people who said they believed the conspiracy theories tended to be less educated, poorer and members of minority groups, they aren't conspiracy nuts, Oliver says. And they aren't ignoring their health. Instead, they are normal people trying to make sense of complex issues.
Corporations and government institutions are complicated organizations with a lot of different motivations. "Public mistrust is understandable," he says.
People who backed the conspiracy theories were less likely to rely on a family doctor. Instead they looked to family and friends, the Internet and celebrity doctors for their health information. And people who relied on celebrity doctors. such as Dr. Mehmet Oz and Dr. Andrew Weil, were most likely to favor conspiracy, with more than 80 percent agreeing with at least one of the theories.
"They think they are accessing a more reliable source of health information than what traditional medicine is providing," Oliver told Shots.
The survey polled 1,351 people online in August and September. The findings were published Monday in JAMA Internal Medicine.
Conspiracy beliefs directly affect how people take care of their health, the survey found.
People who are firm believers in medical conspiracies are less likely to get regular physicals, at 37 percent compared with 48 percent of participants overall. And they were more likely to buy organic or farm-stand foods, shun flu shots and sunscreen, and use vitamins and herbal supplements.
That was true even after the researchers adjusted the results to remove any influence caused by people's socioeconomic status or their level of trust overall.
Interestingly, the pro-conspiracy people came from across the political spectrum, with 35 percent saying they were liberal, compared with 41 percent saying they were conservative.
"The world is a complicated place," Oliver says. "It's difficult to make sense of it. A lot of these conspiracy theories are intuitively compelling."