advertisement



Q & A Library


Print this page | Sign up for free e-bulletins
 | Bookmark This Page

Q
How Dangerous Are CT Scans?
A friend who is a former smoker has a CT of her lungs every year.  Fortunately, nothing bad has shown up, but I worry that all that radiation is dangerous. She’s convinced it’s perfectly safe. Is she right?
A
Answer (Published 8/20/2007)

A "CT" scan or "CAT" scan are terms used to describe a diagnostic technology known as computerized tomography, or computed axial tomography. The CT scanner uses x-rays to take pictures of cross-sections of the body, which are then digitally assembled to give physicians detailed, cross-sectional views of internal organs and tissues. This makes it possible to diagnose lung, liver and pancreatic cancers, measure tumors, and determine their precise location. They have also proved invaluable in diagnosing skeletal injuries and vascular diseases.

Related Weil Products
Dr. Weil's Vitamin Advisor for Your Whole Body - Foods, herbs and drugs can all interact, sometimes in unexpected ways. Dr. Weil's Vitamin Advisor takes known interactions into account when developing nutritional supplement recommendations, to help safeguard against adverse effects. Learn more, and get your free, personalized Dr. Weil's Vitamin Advisor recommendation today.

The downside is that they expose patients to radiation, often as much as 10 to 25 millisieverts (mSv) per test. We know from studies of survivors of the atomic bomb attacks in Japan that cancer incidence increases at radiation doses of 50 mSv. However, experts say that lower levels may also increase cancer risks. And clearly patients who have multiple CT scans can get cumulative radiation exposures that exceed 50 mSv.

The latest scientific word on this subject comes from a U.S. government study scheduled to be released in 2008. According to an article published in the New York Times in June 2007, advance word on the findings suggests that per capita dose of ionizing radiation from imaging exams increased by 600 percent from 1980 to 2006. CT scans are responsible for almost half the estimated collective dose of radiation exposure in the United States. Compared to CT scans, radiation exposure from mammograms amounts to only 0.7 mSv, while bone density tests deliver even less, only 0.01 mSv. a chest x-ray would give only 0.1 mSv. (To find out the amount of radiation exposure you would get from specific tests, log onto www. radiologyinfo.org and click on "Safety.")

You can protect yourself against unnecessary exposure by making sure that recommended CT scans and other tests that involve radiation are really necessary. Ask how much exposure is involved and how appropriate the test is considered for your medical problem. You’re also better off if you have imaging tests at facilities accredited by the American College of Radiation. Accreditation means that the machines have been surveyed and calibrated to make sure that the levels of radiation they emit are correct and that the technicians who run the tests are certified to be competent in operating them.

Andrew Weil, M.D.

Creative Commons License Some Rights Reserved Creative Commons Copyright Notice
A portion of the original material created by Weil Lifestyle, LLC on DrWeil.com (specifically, all question and answer-type articles in the Dr. Weil Q&A Library) is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.

The Weil Vitamin Advisor
Get your FREE personalized vitamin recommendation & supplement plan today!

Dr. Weil on Healthy Aging
Your Online Guide to the Anti-Inflammatory Diet. Start eating for your health - begin your free trial now.

Dr. Weil's Spontaneous Happiness
Achieve emotional well-being
in just eight weeks!
Start your 10-day free trial now!

Vitamin Library
Supplement your knowledge with Dr. Weil's essential vitamin facts. Learn why they are necessary and more.

Dr. Weil's Optimum Health Plan
Your 8-week plan to wellness.
Begin your journey today!
 

Dr. Weil's Head-to-Toe
Wellness Guide

Your guide to natural health.
Use the Wellness Guide today!

Dr. Weil's Anti-Inflammatory Diet Food Pyramid
Our interactive tool can help improve overall health through diet.

Condition Care Guide
Learn about health conditions from acne to vertigo, and Dr. Weil's view of the best treatment options for each.

Healthy Recipes
Discover a treasure trove of healthy, healing foods and creative, delicious ways to prepare them.

Q&A Library
Over 2,000 questions from you
and their corresponding answers
from Dr. Weil.

 
Copyright © 2014 Weil Lifestyle, LLC
Information on this web site is provided for informational purposes only and is not intended as a substitute for the advice provided by your physician or other healthcare professional. You should not use the information on this web site for diagnosing or treating a health problem or disease, or prescribing any medication or other treatment.

Ad Choice
Advertising Notice

This Site and third parties who place advertisements on this Site may collect and use information about your visits to this Site and other websites in order to provide advertisements about goods and services of interest to you. If you would like to obtain more information about these advertising practices and to make choices about online behavioral advertising, please click here