How do medical myths arise? We may be witnessing a case study. Last May, men got a scare when ominous headlines in outlets such as Reuters and the Washington Post warned that iPods might emit enough electromagnetic interference to cause malfunctions in pacemakers, which are heart devices that are more common in men than women. The source for those articles was a study conducted—rather unusually—by a 17-year-old high school student and a family friend and University of Michigan cardiologist, Krit Jongnarangsin, with input from the student's father, R. K. Thaker, who is a cardiologist who specializes in pacemakers.
Yesterday, another study emerged, this one contradicting the first and seemingly more rigorous. According to a summary of the new study published on the website Science Daily, the Food and Drug Administration researcher who led the study tested four different iPod models and found that the peak magnetic field strength was 0.2 millionths of a Tesla, a value hundreds of times lower than the levels capable of interfering with a pacemaker.
Is the Thakers' original notion wrong? I spoke with the elder Thaker to get his take. The new study, he explained, tested for interference using a different technique than he and his son had, so it's not entirely surprising that they seem to come to different conclusions. "What they've found seems very reasonable," he says. "But, the real question is what happens in patients." He and his son, he says, are currently working on a study that will address that question more directly.
"At this stage, there is absolutely no reason at all that patients should be concerned," he says. "Even if we find some evidence of interference in patients, I think it will be more of a medical curiosity than something the public should ever be concerned about," he says. In the testing he has done so far, he says, he hasn't found any evidence that interference can cause any actual medical problems in patients.
Even so, it seems possible that the notion iPods are dangerous for people who have pacemakers could well live on as myth.
Thaker also pointed out that in the past people were very concerned about cellphones interfering with pacemakers. "We have not heard of any cellphones interfering with pacemakers or causing any adverse reactions in the last 10 years," he says. He suggests that that's because the technology has improved and there is better shielding in pacemakers now.
In December, in fact, I briefly reported on seven common medical myths that even many doctors believe. The cellphone myth was one of them.
Other medical myths getting under your skin? Let all of us know by posting a comment below, or E-mail me at firstname.lastname@example.org. And watch this space for updates to the list. For inspiration, you might check out other sites that track purported medical myths.