X-rays, a form of ionizing radiation, have the potential to affect the thyroid gland, but routine medical X-rays such as dental, chest, or mammogram X-rays are generally not linked to the development of thyroid nodules. Thyroid nodules are lumps that form within the thyroid gland, which is located in the neck and produces hormones regulating metabolism. These nodules can be benign (non-cancerous) or malignant (cancerous), and their causes vary widely.
The thyroid gland is sensitive to radiation, especially during childhood, and exposure to high doses of radiation has been associated with an increased risk of thyroid abnormalities, including nodules and cancer. This risk is particularly noted in cases where radiation therapy is used to treat cancers in the head, neck, or chest regions. For example, patients who have undergone radiation treatment for Hodgkin’s lymphoma or breast cancer may have a higher chance of developing thyroid nodules or cancer later in life. Similarly, exposure to radioactive iodine released during nuclear accidents has been linked to a rise in thyroid cancers, especially in children exposed at a young age.
However, the typical doses of radiation from routine diagnostic X-rays are much lower than those used in radiation therapy and are not considered a significant risk factor for thyroid nodules or cancer. Medical guidelines emphasize minimizing unnecessary radiation exposure, but standard X-ray procedures do not usually deliver enough radiation to cause thyroid damage or nodules.
Thyroid nodules themselves are quite common and can be detected incidentally during imaging tests like X-rays or CT scans performed for unrelated reasons. Most thyroid nodules are benign and do not cause symptoms, but some can grow large enough to cause a visible lump or discomfort. When a nodule is found, ultrasound is the preferred method to evaluate its characteristics, such as size, composition, and whether it has suspicious features that might indicate cancer. Nodules larger than 1 cm with suspicious ultrasound features or those growing beyond 4 cm warrant closer examination and possibly a biopsy to determine their nature.
In summary, while high-dose radiation exposure, especially in childhood, can increase the risk of thyroid nodules and cancer, routine X-rays used in medical diagnostics are not known to cause thyroid nodules. The development of thyroid nodules is influenced by multiple factors, including genetics, iodine intake, and other environmental exposures, but everyday X-ray exposure is not a significant cause.