Estimated radiation risks potentially associated with full-body CT screening by David Brenner in the September 2004 issue of the journal Radiology found that a 45-year-old adult who plans to undergo:

One CT full body scan has a 1 in 1250 risk of developing cancer (0.08%);

And he risks, from annual full-body CT examinations up to age 75 (30 examinations), a one in 50 (about 1.9%) chance of developing cancer from the extra radiation.

The authors make the observation that the risk from one full body scan is comparable to the radiation some atomic bomb survivors of Hiroshima and Nagasaki received – where there is clear evidence of cancer risk from radiation.

CT-scans (using computerized machines taking multiple x-rays for one examination) are promoted to people as a preventive measure to find disease long before signs and symptoms develop. Looking for early disease (screening) is very popular because of the hope for prolonging life – perhaps forever. The introduction of CT scan facilities in almost every medium- to large-sized community in developed countries has resulted in millions of people looking for heart disease, and cancers of the lung and colon. However, to date there is no evidence that CT-scanning prolongs life. The FDA, the American College of Radiology, and the US Preventative Task Force do not recommend you have a full-body CT-scan for screening.