Magnetic resonance imaging (MRI) scans are powerful tools used by doctors to help diagnose many different medical conditions. For most people, they are a somewhat stressful test since it is necessary to go into a large tube for the machine to perform the scan. Those with claustrophobia have trouble with it, and the loud noises it makes can also be intimidating. Other than this type of anxiety, however, most people have no trouble with the MRI itself.

A small percentage of patients do have adverse reactions to the contrast dye that needs to be injected before the MRI in order for it to work. According to a 2016 study, about 2.4% of people who get an MRI have a mild reaction to the dye itself. This can include swelling, itchiness, headache, and other similar problems. An even smaller percentage of the population will experience more severe side effects including things like convulsions, low blood sugar, and more.

Scientists have been researching what causes these more severe reactions with the hope that they can be prevented. A University of New Mexico press release says that researchers at the university’s medical school may have found that there is oxalic acid and vitamin C may interact with the gadolinium in the dye. Gadolinium is a heavy metal element that is used in the dye. It allows the MRI’s magnetic field to create the image so that doctors can get a clear picture of the patient’s internal organs.

This is an important find because, while the severe side effects from the dye are rare, they can actually be life threatening. The most dangerous side effects is known as nephrogenic fibrosis, which can cause systemic issues resulting in death in as few as just one injection. Brent Wagner is a coauthor of a paper on the subject, which is published in the journal Magnetic Resonance Imaging, commented in the press release:

“The worst disease caused by MRI contrast agents is nephrogenic systemic fibrosis. People have succumbed after just a single dose.”

The paper suggests that oxalic acid molecules may bind with gadolinium. In experiments, they found that these molecules can leach out of the dye and bind with oxalic acid molecules in the body. From there, they can infiltrate cells and go into the organs, causing life-threatening problems.

Additional research is needed to validate this hypothesis and confirm the experiments, but it is enough to give doctors and patients pause. Wagner commented:

“I wouldn’t take vitamin C if I needed to have an MRI with contrast because of the reactivity of the metal. I’m hoping that we’re getting closer to some recommendations for helping these individuals.”

MRIs are able to provide extremely valuable information, and in many cases, this type of scan is essential for diagnosis and treatment. Avoiding unnecessary MRIs, and making sure to minimize the intake of foods containing oxalates and vitamin C before the dye is injected, however, seems like a reasonable precaution.

Thought that was fascinating? Here’s another story you might like: Why You’ll Never See A Great White Shark In An Aquarium