CT scans have become a vital tool in medicine, using X-rays to create virtual “slices” of your body that help doctors diagnose everything from cancer to internal injury.

But about a third of CT scans are not necessary and needlessly expose patients to radiation, according to Health magazine, which recently took a closer look at the rewards and risks of medical imaging.

Dr. Roshini Raj joins TODAY to discuss the potentially cancer-causing radiation you’re exposed to with every scan and she says that you should talk to your doctor about whether any scan is necessary.

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