CT scans are essential tools used for diagnostic purposes — but according to recent findings, there may be a hidden danger associated with them. TL;DR: Recent research suggests there may be a link between CT scans and cancer risk. But before you panic, let’s unpack the findings and try to gain some clarity on what they can — and can’t — tell us about this risk.
The research, which was published in April of 2025 and posed the question “how many future cancers could result from radiation exposure in the United States?”.
It’s a significant question: According to the study, which appears in JAMA Internal Medicine, approximately 93 million CT exams are performed on 62 million people in the United States every year. According to the study, ionizing radiation is a known carcinogen — but do the amounts transmitted via a CT scan measurably increase a person’s cancer risk?
The study suggests that CT scans could lead to more cancer diagnoses
The study suggests something sobering and alarming: According to the study, at current utilization rates and dosing of CT exams, researchers project 103,000 future cancers over the lifetime of exposed patients. If the current practices around CT scan use stay the same, CT scan associated cancers could account for 5 percent of cancer diagnoses annually.
In 2009, an analysis suggested that 29,000 future cancers would result from CT exposures in 2007 — but now, CT scans are being administered more frequently, exceeding pre-pandemic levels.
So…should we avoid CT scans?
It’s unfortunately not that simple. CT scans are important diagnostic tools, frequently used diseases or injuries, or to plan medical, surgical, or radiation treatments, according to Mayo Clinic.
There are benefits to these scans and benefits to the information they provide providers and patients.
However, as with so many things, it’s about weighing the benefits against the risks.
"Medical imaging has potential benefits," said radiologist Dr. Rebecca Smith-Bindman, an epidemiology professor at the University of California, San Francisco, and lead author of the study published Monday in JAMA Internal Medicine.
"It has potential harms as well, and it's really important to balance them. There's nothing you can do about radiation that you've been exposed to already. But you want to limit future exposure to cases when you really need it," Smith-Bindman says, according to NPR.
The role of self-advocacy
The reality of navigating the medical system, especially as a woman, is that you have to speak up for yourself time and time again. In this context, that means having the tools to push back if you’re unsure about the need for a CT scan.
As the researchers have pointed out, there are both risks and benefits associated with this type of testing, and while it’s always important to listen to medical experts, it’s also okay to ask for a second opinion or an explanation as to why you’ve been asked to get a CT, request another type of testing if it may be appropriate, or an explanation of these findings from a medical provider.
Obviously, these findings are scary, but it’s worth having this type of information so you can better advocate for yourself.
There’s a reassuring component here though
According to Dr. Amit Garg, who spoke about these findings on social media, “the overall risk is low” when it comes to this association.
Based on the data, he says, if a patient has a head CT, their lifetime risk of developing cancer is 1 in 10,000, which increases to 1 in 500 if a full-body CT scan. Typically, according to Dr. Garg, the benefits outweigh the risks here.
It’s also worth noting that MRIs and ultrasounds don’t emit the same radiation that CT scans do.
Keep this piece of advice in mind
"We need patients to ask their doctors, 'Can you use low dose when you scan me?' " Smith-Bindman says, according to NPR. "It's crazy that patients have to ask for it, but it's actually really successful."