A bone CT scan does expose you to radiation, but whether it is considered “a lot” depends on the context and comparison to other imaging methods. CT scans in general use X-rays to create detailed images of the body, including bones, and they deliver higher doses of radiation than standard X-rays. However, the amount of radiation from a bone CT scan is still carefully controlled and optimized to be as low as possible while providing clear diagnostic images.
To understand this better, it helps to know that radiation exposure is measured in millisieverts (mSv), which quantifies the effect of ionizing radiation on the body. Natural background radiation that everyone receives from the environment averages about 3 mSv per year. A typical bone CT scan might expose you to radiation doses in the range of a few millisieverts, often higher than a simple X-ray but lower than some other CT scans of larger body parts like the abdomen or chest.
CT scans contribute significantly to medical radiation exposure overall, accounting for about a quarter of all radiation from medical imaging in the U.S. This is because CT scans are more detailed and thus use more radiation than standard X-rays. Despite this, the risk from a single bone CT scan remains relatively small. The increase in lifetime cancer risk from one scan is slight, but it is not zero. Radiation can cause DNA damage, which in rare cases may lead to cancer many years later.
Medical professionals follow the ALARA principle—”As Low As Reasonably Achievable”—to minimize radiation doses during CT scans. This means using the lowest radiation dose possible to get the necessary diagnostic information. Modern CT machines are more efficient and use lower doses than older models. Additionally, doctors only recommend CT scans when the benefits of accurate diagnosis and treatment planning outweigh the small risks from radiation exposure.
For patients concerned about radiation, there are ways to reduce potential harm. Some research suggests that taking antioxidants such as vitamin C, N-acetylcysteine (NAC), lipoic acid, and beta-carotene before a CT scan may help neutralize free radicals created by radiation and protect DNA and bone cells from damage. This antioxidant protocol is not yet standard practice everywhere but shows promise in reducing radiation-related risks.
It is also important to distinguish between a bone CT scan and a bone scan (bone scintigraphy). A bone scan involves injecting a small amount of radioactive tracer that collects in bones and is detected by a special camera. The radiation dose from a bone scan is generally comparable to that of a regular X-ray and is usually lower than that from a CT scan. Bone scans and CT scans serve different diagnostic purposes, so your doctor will choose the best test based on your medical needs.
In summary, a bone CT scan does expose you to more radiation than a standard X-ray, but the dose is carefully managed and considered low enough that the benefits of accurate diagnosis outweigh the risks in most cases. If you have concerns, discussing them with your healthcare provider can help you understand why the scan is recommended and what precautions can be taken to minimize radiation exposure.