Radiation causes cancer. That is an unequivocalfact. Everything is dose-response. Tobacco causescancer but obviously one cigarrette will not causecancer. The same goes for red meat, alcohol, hormone replacement therapy, and every otherknown cause of cancer. It is well known and well accepted by scientists, physicians,the radiology community that thyroid cancers and lymphomasare higher in x-ray techs and radiologists. It's estimated in a NEJM study (dec 15th, 2009) that excessCAT scans will cause 29,000 cancer deaths per year.This is more deaths than HIV! CT scan of the colon is 1,000 x-rays of the teethor 1,000 x-rays of the arm. Your logic is determing whether or not a CAT scan (CT SCAN)is harmful is flawed. You posit that one's exposure during a lifetimewill determine cancer risk. First, since one can not readthe future, one should use the precautionary principle. We may get heart disease in the future and may have to doCAT scans. Second, one CAT scan combined with other environmental factors(diet, red meat, lack of exercise, tobacco, alcohol, etc.) can actuallycause cancer. Cancer is not the result of one exposure, as I mentionedbefore. Different factors can work synergistically to cause cells toproliferate. The key is to minimize as much exposure to known carcinogens.While some people assume everything causes cancer, there are actuallyfew known causes and these causes make up the majority of cancers.Because of this, the pill cam is by far the wisest choice for visualization ofthe small bowel and yes the colon mucosa as well. The majority of the population views colonscopy as embarassing, invasiveand are not quick to undergo a procedure that requires sedation.We must not forget that many people on this board are scared or embarrassedto get a colonoscopy. We must embrace procedures that remove the fearand humility associated with other procedures.