October is Breast Cancer Awareness Month, and thousands of well-meaning healthcare providers will continue to recommend mammograms. However, a growing body of research suggests that X-ray mammography may not be the best screening approach, at least on an annual basis, and even the National Cancer Institute notes potential harms ranging from false results to overtreatment and radiation exposure.

A 2006 study published in the British Journal of Radiobiology revealed that the type of radiation used in X-ray-based screenings is more carcinogenic than previously believed. The researchers wrote, “Recent radio-biological studies have provided compelling evidence that the low-energy X-rays used in mammography are approximately four times—but possibly as much as six times—more likely to cause mutational damage than higher energy X-rays.”

Peter Gøtzsche is director of the Nordic Cochrane Centre and an author of the landmark 2001 Cochrane systematic review, Screening for Breast Cancer with Mammography, which concludes, “Currently available reliable evidence has not shown a survival benefit of mass screening for breast cancer.” In 2011, Gøtzsche stated, “It is getting more and more difficult to argue that mammography is reasonable to [use] for breast screening.”