The Fukushima nuclear disaster that rocked Japan in 2011, has sparked world-wide fear and concern. With news of radiations still leaking into the environment and even drifting on to the American shores and around the world’s oceans, it looks like the crisis is far from over.
Ionizing radiations crash into the living cells and knock off their electrons, rendering them highly unstable and leading to the formation of free radicals in excess. These molecules damage DNA, proteins and lipids – increasing the risk of cancer, genetic mutations, birth defects, cardiovascular disease and poor immune functions.
However, these health concerns are not limited to radiation fallout in accidents, as happened during the Chernobyl and Fukushima nuclear disasters. Emerging evidence suggests that low doses of ionizing radiations, emitted during X rays, CT scans, airport screening and even air travel, can increase one’s risk of developing both cancer and non-cancer diseases over long term. Most compelling data for this damage exists for cardiovascular disease   and cataracts. 
Can vitamin C offer any protection?
Vitamin C works as a radio-protector
Vitamin C is a strong anti-oxidant – a substance that keeps a check on free radicals.
A Japanese study by Dr. Atsuo Yanagisawa showed that Vitamin C was helpful in protecting Fukushima workers from radiation induced DNA damage and reduced overall cancer risk. The researchers concluded that “Workers with severe radiation exposure at the Fukushima nuclear plant had major reduction in cancer risk when supplemented with vitamin C and other anti-oxidative nutrients” 
This attests to what we already know from another study that showed vitamin C protects against accidental exposures or those received during medical scans, especially when “radionuclides are incorporated in the body and deliver the dose in a chronic fashion.” 
Harmful radionuclides cleverly imitate other nutrients. For example, Cesium 137 mimics potassium and accumulates in the heart that need potassium for healthy muscle contractions. Strontium-90 mimics calcium and is deposited in bones and teeth. Iodine 131 mimics iodine and is concentrated in thyroid glands that need iodine for proper functioning.
This masquerade gives them easy access into bones, the thyroid, and various organs such as the liver, heart and brain. Once inside, they keep emitting radiations in a chronic fashion over time, damaging tissues and organs. Experts agree that this kind of internal exposure carries far greater risk than exposure from outside.
Vitamin C also helps improve your body’s immunity. Several cells of the immune system, including T cells and phagocytes, require vitamin C to do their job. T cells are used by the body to fight and kill infected and cancerous cells and these cells are particularly vulnerable to the damage caused by radiations.  .
Radiations disable the body’s immune engine by targeting bone marrow. Now, bone marrow production is one of the busiest tasks the body undertakes. It contains stem cells that are always rapidly dividing to produce white blood cells, red blood cells and platelets. White blood cells further mature into all kinds of formidable immune cells such as macrophages, dendritic cells, B cells, T cells and natural killer cells.
It is a well-known fact that radiations affect rapidly multiplying cells the most. That’s why bone marrow is hit particularly hard when exposed to ionizing radiations – leading to depletion of white blood cells (along with platelets and red blood cells). In fact, most symptoms of radiation sickness are a consequence of bone marrow damage. Bleeding from gums, nose and rectum happens due to low levels of platelets. There is an increased risk of infections with reduced levels of white blood cells. And you suffer overall weakness and anemia as a result of depleted red blood cells.
Bone marrow transplantation works as an effective strategy to prevent complete bone marrow failure in patients exposed to a lethal radiation dose. However, this is usually accompanied by radiation-induced gastrointestinal syndrome. Now, a 2010 study on mice showed that pre-treatment with ascorbic acid supressed an increase in free radical metabolites and DNA damage. Vitamin C donates hydrogen to radiation induced free radicals in bone marrow as well as the GI (gastrointestinal tract). This step helps in chemical repair of damaged DNA. 
What is most important to consider, therefore, is that studies show that vitamin C reduces the severity of side effects from chemotherapy and radiation therapy, thus improving the quality of life in cancer patients.
Worried about any potential radiation exposure? It seems like a sensible strategy to maintain high concentrations of vitamin C in your tissues, especially before or at the time of exposure.
- Azimzadeh et al. Proteome analysis of irradiated endothelial cells reveals persistent alteration in protein degradation and the RhoGDI and NO signalling pathways. Internation Journal of Radiation Biology. 2017
- Tapio S. 2016. Pathology and biology of radiation-induced cardiac disease. J Radiat Res. 57:439–448.
- Chodick et al. Risk of cataract after exposure to low doses of ionizing radiation: a 20-year prospective cohort study among US radiologic technologists. Am J Epidemiol. 2008
- Yanagisawa A. Orthomolecular approaches against radiation exposure. Presentation Orthomolecular Medicine Today Conference. Toronto 2011 http://www.doctoryourself.com/Radiation_VitC.pptx.pdf )
- Narra VR, Howell RW, Sastry KS, Rao DV. Vitamin C as a radioprotector against iodine-131 in vivo. J Nucl Med 1993; 34(4):637-40
- Heng-Hong Li et al. Ionizing Radiation Impairs T Cell Activation by Affecting Metabolic Reprogramming. Int J Biol Sci. 2015
- SM Candéias et al. Low-dose radiation accelerates aging of the T-cell receptor repertoire in CBA/Ca mice. Cell Mol Life Sci. 2017
- Pretreatment with Ascorbic Acid Prevents Lethal Gastrointestinal Syndrome in Mice Receiving a Massive Amount of Radiation J. Radiat. Res., 51, 145–156 (2010)
- Anitra C. Carr, Margreet C. M. Vissers, and John S. Cook. The Effect of Intravenous Vitamin C on Cancer- and Chemotherapy-Related Fatigue and Quality of Life. Frontiers in Oncology. 2014; 4: 283.