Why Do You Lose Hair When Exposed to Gamma Rays?

Discovered by French physicist Henri Becquerel in 1896, gamma rays are emitted from unstable radioactive material such as uranium. The rays are high-energy, travel at the speed of light and can penetrate most materials, including human tissue.

Radiation

• Gamma rays travel vast distances at high speeds and pass through the body, ionizing the cells and tissues and changing their structure permanently. This change of cell structure causes radiation sickness, with its symptoms such as hair loss. Fortunately, exposure to gamma rays needs to be severe for hair loss to occur.

Hair Loss

• Only moderate to severe exposure to gamma rays causes hair loss. Exposure is measured in units named "gray," or Gy. According to the Mayo Clinic, symptoms develop within one to four weeks if the exposure is between 2 and 6 Gy. With very severe exposure -- 8 to 10 Gy -- hair loss is immediate. Close proximity to radioactive fallout from a nuclear reactor, as seen at Chernobyl, is a severe exposure situation. X-rays and other diagnostic tests do not emit enough rays to cause this symptom.

Considerations

• People ingest gamma rays naturally through food and water. High potassium foods are a well-known source. Nuclear medicine, along with manmade radionuclides, such as Cobalt 60 and Cesium137 used in industrial processes, add to our exposure. Both internal and external sources of gamma rays are a health concern, but food sources are unlikely to cause hair loss because they contain low amounts of radiation.