Whole Body Imaging for Health Screening

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Whole body imaging is a computed tomography (CT) or magnetic resonance imaging (MRI) scan of your entire body. The scan generates cross-sectional images for a radiologist to review, potentially revealing tumors, cysts, gallstones, arthritis, calcium deposits, and a whole host of other abnormalities. 

On face value, a whole body scan seems like a wise method for screening for health problems. Most of us would want to know if we had a serious disease.

 On the other hand, a negative scan might offer us much peace of mind. 

If given the opportunity, should you have a whole body imaging scan for screening? This article will outline the key issues to consider.  

Diagnostic vs screening exams

The purpose of a diagnostic exam is to determine what may be causing a symptom, lab abnormality, or other sign of disease. For example, somebody with rectal bleeding may have a diagnostic colonoscopy to find the source of the bleeding. 

A screening exam is performed in order to detect a disease or medical condition before signs or symptoms appear. An example of a screening exam is a colonoscopy, sigmoidoscopy, or stool test to detect colorectal cancer in somebody 50 years of older who doesn't have signs or symptoms of the disease. The goal is to detect colorectal cancer or precancerous polyps at an early stage. A whole body CT or MRI for screening would be done to detect disease in a healthy person who has no signs or symptoms of disease.

Whole body imaging is available at some radiology centers for those who wish to self-refer (arrange for the test without an order from their physician). They are also part of some "executive physicals," which are offered by companies to their top executives.

False positives

If you have a whole body CT or MRI, the scan will probably find something.

 A 2014 study of 666 people who had whole-body MRIs found that 99% had at least one abnormality.

However, an abnormality on an imaging study does not always indicate a health problem. In fact, the vast majority of incidentally-discovered abnormalities found on screening whole body scans don't have any significant impact on health. But following up on these abnormalities can lead you down a slippery slope of unpleasant experiences, such as:

  • Risky follow-up tests, such as biopsies
  • Risky treatments which don't improve long-term health
  • Anxiety while undergoing follow up tests and treatment
  • Unnecessary expense

All of this can be avoided if the whole body scan wasn't done in the first place.

False negatives

If the whole body CT or MRI is negative, the peace of mind could actually lull you into a false sense of security. The scans don't detect major health problems like hypertension or diabetes. There's also the possibility that people with negative scans would use it as an excuse to continue unhealthy habits, such as smoking, poor diet, and sedentary behavior.

Scans without the use of intravenous contrast are not sensitive for detecting abnormalities in the abdomen. And scans with intravenous contrast can cause problems, as discussed below.

Inherent risks of the scans

The scans carry their own risks, regardless of false positives and false negatives. CT scans use much more radiation than regular x-rays, with some concern that whole body CT delivers enough radiation to increase the risk of cancer. Intravenous contrast, if used, can cause kidney damage and allergic reactions. 

Position statements

Statements against whole body CT screening were issued in 2002 by the American College of Radiology, a non-profit professional medical association for radiologists, and in 2009 by the U.S. Food and Drug Administration. There hasn't been enough evidence in favor of whole body screening to change these recommendations

CT for targeted screening

While whole body scanning is not recommended for screening, targeted exams for people with certain risk profiles can be useful. For example, a CT scan of the chest is recommended for detecting lung cancer in some individuals with a heavy smoking history.


We have long since had the technology for screening whole body scans. However, advanced technology does not always translate into meaningful benefits. For health screening, patients and health care providers are much better off with screening tests based on solid scientific evidence.

[Mention of a commercial product or service does not constitute an endorsement.]


American College of Radiology. ACR Statement on Whole Body CT Screening. September 28, 2002. Accessed on January 1, 2015.

Brenner DJ and Elliston CD. Estimated Radiation Risks Potentially Associated with Full-Body CT Screening. Radiology 2004;232:735–738. Accessed on January 3, 2015.

Cieszanowski A et al. Non-contrast-enhanced whole-body magnetic resonance imaging in the general population: the incidence of abnormal findings in patients 50 years old and younger compared to older subjects. PLoS One 2014;9(9):e107840. Accessed on January 1, 2015.

Furtado CD et al. Whole-body CT screening: spectrum of findings and recommendations in 1192 patients. Radiology 2005;237(2):385-94. Accessed on January 1, 2015.

U.S. Food and Drug Administration. Whole-Body CT Screening--Should I or shouldn't I get one? Accessed on January 1, 2015.

U.S. Preventive Services Task Force. USPSTF A and B Recommendations. Accessed on January 1, 2015.

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