Featured Research

from universities, journals, and other organizations

Task Force Finds Little Evidence To Support Use Of Vitamin Supplements To Prevent Cancer Or Heart Disease

Date:
July 4, 2003
Source:
Agency For Healthcare Research And Quality
Summary:
The U.S. Preventive Services Task Force has concluded there was insufficient scientific evidence to recommend vitamin supplements as a way to prevent cancer or heart disease and recommended against the use of beta carotene supplements in smokers because of a possible increased risk of lung cancer and death.

June 30, 2003 -- The U.S. Preventive Services Task Force today concluded there was insufficient scientific evidence to recommend vitamin supplements as a way to prevent cancer or heart disease and recommended against the use of beta carotene supplements in smokers because of a possible increased risk of lung cancer and death. The Task Force conclusions are based on a review of studies on the use of vitamins A, C, or E, multivitamins with folic acid, or antioxidant combinations to reduce the risk for cancer or cardiovascular disease in adults. These findings are published in the July 1 issue of the Annals of Internal Medicine.

The Task Force is the leading independent panel of private-sector experts in prevention and primary care and is sponsored by the Agency for Healthcare Research and Quality. This marks the first time the Task Force has reviewed studies on the effect of vitamins to reduce cancer and cardiovascular disease.

The Task Force reviewed the results of four clinical trials that found that taking beta carotene did not decrease the risk for lung, prostate, colon, breast, or non-melanoma skin cancer in middle-aged and older adults. Two of these clinical trials found that individuals who take beta carotene and smoke have an increased risk of lung cancer and death.

The Task Force also reviewed both randomized trials and observational studies to determine whether taking vitamins A, C, or E, multivitamins with folic acid, or antioxidant combinations reduced risk of heart disease, stroke or various cancers. The best studies suggested no clear benefit of taking vitamins, but the number and length of the studies was insufficient to rule out possible benefits of long-term vitamin use. Although some of the observational studies suggested possible benefits for some cancers, the Task Force could not determine whether these benefits were due to vitamins or to healthier lifestyles in people who take vitamins. They also did not review evidence on the use of vitamins for patients with known nutritional deficiencies, pregnant and lactating women, children, the elderly, and people with chronic illness. Vitamins may be more appropriate for people in these groups, and the Task Force urges those patients to talk with their clinicians about the potential benefits and harms of using vitamins.

"Vitamin supplements may be necessary for individuals whose diets don't provide the recommended amounts of specific vitamins and especially important for pregnant and nursing women and people with specific illnesses. However, the benefits of vitamin supplements for the general population remain uncertain," said Janet Allan, Ph.D, R.N., vice chair of the Task Force. "There are currently a number of important studies underway which might help answer this important question."

Although most studies reviewed by the Task Force showed that taking vitamins according to the Recommended Daily Allowance does not cause harm, several adverse effects can be caused by taking moderate doses and/or excessive doses of certain vitamins. For example, moderate doses of vitamin A may reduce bone mineral density, and high doses may cause liver damage or in pregnant women, harm to a fetus. The Task Force recommends that patients who take vitamins not take more than the Recommended Daily Allowance and talk to their clinician about the effects vitamins may have on their health.

The Task Force conducts rigorous, impartial assessments of all the scientific evidence for a broad range of preventive services. Its recommendations are considered the gold standard for clinical preventive services. The Task Force based its conclusion on a report from a team led by Cynthia Morris, Ph.D., M.P.H., and Cheryl Ritenbaugh, Ph.D, M.P.H., from AHRQ's Evidence-based Practice Center at Oregon Health & Science University in Portland.

The Task Force grades the strength of the evidence from "A" (strongly recommends), "B" (recommends), "C" (no recommendation for or against), "D" (recommends against) or "I" (insufficient evidence to recommend for or against screening). The Task Force recommends against the use of beta carotene supplements, either alone or in combination, for the prevention of cancer or cardiovascular disease (a "D" recommendation). The Task Force found insufficient evidence to recommend for or against the use of supplements of vitamins A, C, or E, multivitamins with folic acid, or antioxidant combinations for the prevention of cancer or cardiovascular disease (an "I" recommendation).

The vitamin supplementation recommendations and materials for clinicians will be available on the AHRQ Web site at http://www.ahrq.gov/clinic/3rduspstf/vitamins/vitaminsrr.htm. Previous Task Force recommendations, summaries of the evidence, easy-to-read fact sheets explaining the recommendations, and related materials are available from the AHRQ Publications Clearinghouse by calling (800) 358-9295 or sending an e-mail to ahrqpubs@ahrq.gov. Clinical information is also available from the National Guideline Clearinghouse at http://www.guideline.gov.


Story Source:

The above story is based on materials provided by Agency For Healthcare Research And Quality. Note: Materials may be edited for content and length.


Cite This Page:

Agency For Healthcare Research And Quality. "Task Force Finds Little Evidence To Support Use Of Vitamin Supplements To Prevent Cancer Or Heart Disease." ScienceDaily. ScienceDaily, 4 July 2003. <www.sciencedaily.com/releases/2003/07/030701230232.htm>.
Agency For Healthcare Research And Quality. (2003, July 4). Task Force Finds Little Evidence To Support Use Of Vitamin Supplements To Prevent Cancer Or Heart Disease. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2003/07/030701230232.htm
Agency For Healthcare Research And Quality. "Task Force Finds Little Evidence To Support Use Of Vitamin Supplements To Prevent Cancer Or Heart Disease." ScienceDaily. www.sciencedaily.com/releases/2003/07/030701230232.htm (accessed September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins