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The holiday season is upon us, and with millions of Americans expected to be traveling over the next few weeks there will be many more airport body scans than usual done by the U.S. Transportation Security Administration (TSA). Gone are the days of metal detectors and baggage screening alone as the means for airport security: The TSA introduced advanced imaging technology (AIT), better known as full-body scanners, as a primary screening modality in 2009. The widespread use of this technology across the U.S. ramped up after a passenger flying to Detroit successfully smuggled explosives in his underwear onto a U.S.-bound flight on Christmas Day of that year. But AIT was introduced to airports across the country with very little transparency for passengers. As a result, most of the general public probably does not realize there is minimal proof these technologies actually prevent terrorist attacks, and there have been no long-term studies about their safety and efficacy. As a physician, I cannot help but question the risk/benefit balance involved. I have worried about risk ever since their initial implementation, and I have never set foot in a body scanner despite extensive air travel over the years—I always choose to “opt out” instead. The lack of clear benefit with no complete absolution of risk begs the question: Why is the TSA expanding the distribution of body scanners instead of getting rid of them? The History of TSA Body Scanners When AIT was initially rolled out, the TSA had two modes of screening: backscatter x-ray scanners and millimeter wave body scanners. Backscatter x-ray scanners used low doses of radiation in order generate a computerized image of the entire body These scanners came under significant fire by several different groups, including physicians and experts in the field of radiological research, due to their use of ionizing radiation—the kind that can break apart molecules. In a special report in 2011 for the Archives of Internal Medicine (now JAMA Internal Medicine) radiologists helped the public understand dose equivalents to the backscatter machines—with 50 TSA scans being equivalent to the exposure of one dental x-ray, a thousand scans roughly equivalent to a single chest X-ray, and so on.