Antioxidants for Radiation Protection

Questions from the Clinic:

Hey doc, I know radiation is dangerous and may damage normal cells in certain doses. How do I reduce or avoid the potential of damage from therapeutic and diagnostic X-ray tests that are recommended for my cancer treatment, workup and follow-up?

Figure 1: CT scans use computer-processed X-rays to produce images of specific areas of the body. Although the information gleaned from these scans help medical personnel diagnosed various conditions in patients, these devices expose nearby individuals to harmful, ionizing radiation. Image courtesy of Irvine Urgent Care.

I. Introduction

Over the last few decades, increased use of medical imaging modalities such as the computed tomography (CT) scan has resulted in substantially greater patient exposure to ionizing radiation.(1) According to a report published by the National Council on Radiation Protection and Measurements, Americans received seven times as much ionizing radiation from medical procedures in 2006 than they did during the early 1980s. At the time the survey was conducted, investigators additionally noted that medical imaging accounted for nearly half of the total radiation exposure in the United States population.(2) Even though doses associated with individual scans have decreased, low levels of radiation exposure pose significant risks to human health and elevate the risk for various forms of cancer.(3,4) More concentrated forms of radiation, used to treat many forms of cancer, can also cause serious side effects such as secondary cancers to occur.(5) These well-characterized drawbacks of ionizing radiation necessitate the examination of prophylactic radioprotective agents – substances that can be taken before radiation exposure to minimize cellular damage.

II. Mechanism of Action

When ionizing radiation passes through cells, it interacts with water and other, small oxygen-containing molecules to produce a subclass of free radicals known as reacti