They assert that low doses of radiation stimulate protective responses and help the body prevent additional damage over time, including that of subsequent, higher radiation exposures.

A study on the life spans of Japanese atomic bomb survivors, which the article cites as "the gold standard for estimating radiation effects in humans" found that low-dose carcinogenicity predicted with the LNTH is invalid below about 200 milligray (mGy). The doses of typical imaging exams can range from a fraction of a millisievert (mSv) for regular X-ray to 15 mSv for whole-body FDG PET/CT. One mSv is the dose produced by exposure to 1 mGy of radiation


The American College of Radiology recommends limiting lifetime diagnostic radiation exposure to 100 mSv. That is equal to 10,000 chest X-rays, or up to 25 chest CTs, according to Harvard Medical School.

The study authors argue that the real danger is when these valuable diagnostic exams are avoided due to "radiophobia."

An opinion piece published in the June issue of the American Journal of Roentgenology discussed the difference between the public’s perception of radiation risk and the actual risk from low doses of ionizing radiation.

Dr. Cynthia H. McCollough of Mayo Clinic explained that if the exam is needed, the benefit will outweigh “any small or potentially nonexistent risk.” She also noted the importance of adjusting the delivered dose to the patient size and to the diagnostic task.

“There have been too many polarizing articles on the topic of radiation dose in CT. These articles serve only to perpetuate the discussion, leaving patients and their families with the impression that this issue is a deeply concerning one,” she said in a statement.

The authors of the JNM article believe that the medical profession must be properly re-educated, starting with diagnostic radiologists and nuclear medicine physicians, then the public can be given valid information that they can trust.

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