“What damage does radiation do to the body?”

It depends on the type of radiation. Low energy non ionizing radiation like radiofrequency waves, i.e., iPhones are all around us all the time and cause no damage under normal circumstances. High energy ionizing radiation, i.e., X-rays and gamma rays, have enough energy to damage DNA within cells and can sometimes result in cancer.

To answer your question, it is first important to understand how radiation works. Radiation is a form of x-ray, created by a machine that accelerates electrons to a very high speed. This stream of electrons is shaped into a beam and is directed at the body parts intended for treatment. The radiation penetrates deep into the body, allowing it to target sites internally. The energy from radiation is high enough to create "free radicals", which are highly unstable atoms and molecules, and these free radicals cause breakage of the DNA strands, leading to death of the cells. There are two categories of damage from radiation: short-term damage and long-term damage. The kind of specific damage also depends on the site of radiation, and the amount of radiation. In general, short-term damage includes burning (similar to a bad sunburn), inflammation, swelling, ulceration of the mucus membrane. You may have fatigue, pain, and some other site-specific symptoms (depending on which part of the body is receiving the treatment). Long-term damage includes possible irreversible damage to an organ, and an increased risk of cancer. Remember that every medical treatment has side effects and risks. For cancer treatments, the side effects and risks are even more severe. Nonetheless, if a treatment is recommended, it is because the benefits far outweigh the side effects and risks.

Vinh-Linh Nguyen, M.D.