ahrq-gov/archive.ahrq.gov/research/jul03/0703RA33.htm
2025-02-28 14:14:25 -05:00

167 lines
No EOL
14 KiB
HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Research Activities, July 2003: Agency News and Notes: Task Force finds little evidence to support use of vitamin supplements to prevent cancer or heart disease</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<!-- "metadata" -->
<meta name="Title" content="Research Activities, July 2003" />
<meta name="keywords" content="Agency for Health Care Policy and Research, Agency for Healthcare Research and Quality, AHRQ, AHCPR, AIDS/HIV, ambulatory care, benchmark, child, cost, elderly, health cost, healthcare cost, hospital, long-term care, managed care, markets, mental health, methodology, minority health, nursing, nursing homes, outcome research, out-of-pocket spending, patient care, primary, primary care, research, rural, spending, study, Translating Research Into Practice, TRIP" />
<meta name="description" content="Online newsletter summarizing published findings from AHRQ-funded studies, new AHRQ publications and products, and funding opportunities." />
<meta name="creator" content="Agency for Healthcare Research and Quality (AHRQ)" />
<meta name="datecreated" content="July 2003" />
<meta name="datereviewed" content="July 2003" />
<meta name="language" content="English" />
<!-- end metadata -->
<link href="/includes/archive.css" rel="stylesheet" type="text/css" />
<link href="/includes/ahrqstyleprint_arch.css" rel="stylesheet" type="text/css" media="print" />
<script>
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-75759936-1', 'auto');
ga(' set', 'anonymizeIp', true);
ga('send', 'pageview');
</script></head><body><!-- Google Tag Manager -->
<noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-W4DST4"
height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
'//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
})(window,document,'script','dataLayer','GTM-W4DST4');</script>
<!-- End Google Tag Manager -->
<noscript>
Your browser doesn't support JavaScript. Please upgrade to a modern browser or enable JavaScript in your existing browser.
</noscript>
<!-- Page Header v2.0 -->
<a name="top" id="top"></a>
<!--Begin Banner CodeS-->
<div id="ahrqbanner">
<div class="hhsportion">
<a href="#h1" class="skipnav">Skip Navigation</a>
<a href="http://www.hhs.gov" title="U.S. Department of Health and Human Services">
<img src="/images/hhs_banner.gif" alt="U.S. Department of Health and Human Services" />
</a>
<a href="http://www.hhs.gov" title="www.hhs.gov" class="hhsright">
<img src="/images/hhs_link.gif" alt="www.hhs.gov" />
</a>
</div>
<div class="ahrqportion">
<a href="/" title="Archive: Agency for Healthcare Research Quality">
<img src="/images/ahrq_banner.gif" alt="Agency for Healthcare Research Quality" />
</a><form name="searchForm" method="get" action="https://search.ahrq.gov/search" id="banner_searchform">
<label for="search" style="z-index:-1;position:relative;margin-right:-65px; font-size:0px;">Search</label>
<input name="q" type="text" value=" Search Archive" size="11" onfocus="this.value='';" class="gotext" label="Search archive" id="search" />
<input type="hidden" name="entqr" value="0" />
<input type="hidden" name="output" value="xml_no_dtd" />
<input type="hidden" name="proxystylesheet" value="ARCHIVE_Front_End" />
<input type="hidden" name="client" value="ARCHIVE_Front_End" />
<input type="hidden" name="site" value="ARCHIVE_AHRQ_GOV" />
<input src="/images/topbn_GoButton.gif" class="gobtn" name="Submit" onclick="javascript:document.searchForm.submit();" type="image" alt="Search" />
</form>
<a href="https://www.ahrq.gov/" class="ahrqright">www.ahrq.gov</a>
</div><div class="ahrqlinks"><a href="https://www.ahrq.gov/">AHRQ Home&#8212;Live Site</a> | <a href="/">Archive Home</a> | <a href="/sitemap.htm">Site Map</a> <!-- | &nbsp;<img src="/images/envelope1.jpg" alt="" width="21" height="14" /><a href="https://subscriptions.ahrq.gov/service/multi_subscribe.html?code=USAHRQ">E-mail Updates</a> --></div>
</div>
<div id="PrintBanner">
<img src="/images/printbanner_arch.jpg" alt="Archive print banner" />
</div>
<a name="h1"></a>
<!-- End banner code -->
<!-- End of Page header -->
<!-- Content Body -->
<div id="mainContent">
<table width="100%" border="0" cellspacing="0" cellpadding="0" >
<tr valign="top">
<td width="70%">
<!-- Center Content section -->
<table width="100%" border="0" cellpadding="0" cellspacing="0" style="margin-left:10px; margin-right:10px;margin-top:5px" summary="This table gives the layout format of the bread crumb area and the center content area.">
<!--DWLayoutTable-->
<tr>
<td class="crumb_link"><div id="crumbContent">
<p><strong>You Are Here:</strong> <span class="crumb_link"><a href="/" class="crumb_link">AHRQ Archive Home</a> &gt; <a href="/research/resarch.htm" class="crumb_link"><em>Research Activities</em> Archive</a> &gt; <a href="." class="crumb_link">July 2003</a> </span></p>
</div>
</td>
</tr>
<tr>
<td><h1><a name="h1" id="h1"></a> Agency News and Notes</h1>
</td>
</tr>
<tr>
<td><div id="centerContent"><div class="headnote">
<p>This information is for reference purposes only. It was current when produced and may now be outdated. Archive material is no longer maintained, and some links may not work. Persons with disabilities having difficulty accessing this information should contact us at: <a href="https://info.ahrq.gov/">https://info.ahrq.gov</a>. Let us know the nature of the problem, the Web address of what you want, and your contact information. </p>
<p>Please go to <a href="https://www.ahrq.gov/">www.ahrq.gov</a> for current information.</p></div>
<h2><a name="head1">Task Force finds little evidence to support use of vitamin supplements to prevent cancer or heart disease</a></h2>
<p>The <a href="https://www.ahrq.gov/clinic/uspstfix.htm">U.S. Preventive Services Task Force</a> has concluded that there is insufficient scientific evidence to recommend vitamin supplements as a way to prevent cancer or heart disease. In addition, the Task Force has 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.</p>
<p>These findings are published in the July 1 issue of the <em>Annals of Internal Medicine</em>.</p>
<p>The Task Force, which is the leading independent panel of private-sector experts in prevention and primary care, 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.</p>
<p>The Task Force reviewed the results of four clinical trials which 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. </p>
<p>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 were 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. </p>
<p>The Task Force 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 patients in these groups to talk with their clinicians about the potential benefits and harms of using vitamins.</p>
<p>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 that the patients talk with their clinicians about the effects vitamins may have on their health.</p>
<p>The Task Force conducts rigorous, impartial assessments of all the scientific evidence for a broad range of preventive services. Task Force recommendations are considered the gold standard for clinical preventive services. The Task Force based its conclusions 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 <a href="https://www.ahrq.gov/clinic/epc/ohsuepc.htm">Evidence-based Practice Center at Oregon Health &amp; Science University</a> in Portland. </p>
<p>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).</p>
<p>Select for <a href="http://www.uspreventiveservicestaskforce.org/uspstf/uspsvita.htm">vitamin supplementation recommendations and materials</a> for clinicians.</p>
<p>The findings also are published in "Routine vitamin supplementation to prevent cancer and cardiovascular disease: Recommendations and rationale," in the July 1, 2003, <em>Annals of Internal Medicine</em> 139(1), pp. 51-55. </p>
<p>Previous Task Force recommendations, summaries of the evidence, easy-to-read fact sheets explaining the recommendations, and related materials are available from the <a href="https://www.ahrq.gov/research/publications/order/order-research-activities.html">AHRQ Publications Clearinghouse</a>. </p>
<p>Clinical information is also available from the National Guideline Clearinghouse&#8482;. </p>
<p class="size2"><a href=".">Return to Contents</a><br />
<a href="0703RA34.htm">Proceed to Next Article</a></p>
<div class="footnote">
<p> The information on this page is archived and provided for reference purposes only.</p></div>
<p>&nbsp;</p>
</div>
</td>
</tr>
</table>
<!-- End of Center Content section -->
</td>
</tr>
</table>
</div>
<!-- End of Content Body -->
<!-- Footer graphic 1.2-->
<table cellspacing="0" cellpadding="0" border="0" width="100%">
<tr>
<td width="125" background="/images/bottom_ahrq_bkg.jpg"><img src="/images/bottom_ahrq_1.jpg" width="125" alt="AHRQ" /></td>
<td width="100%" background="/images/bottom_ahrq_bkg.jpg" ><img src="/images/bottom_ahrq_bkg.jpg" width="10" height="34" alt="" /></td>
<td width="310" background="/images/bottom_ahrq_bkg.jpg"><img src="/images/bottom_ahrq_2.gif" alt="Advancing Excellence in Health Care" width="310" height="34" /></td>
</tr>
</table>
<!-- Footer links section -->
<div id="banner_Footer2"><p> <a href="https://www.ahrq.gov/">AHRQ Home</a> | <a href="https://info.ahrq.gov" class="footer_navlink">Questions?</a> | <a href="https://www.ahrq.gov/contact/index.html" class="footer_navlink">Contact AHRQ</a> | <a href="https://www.ahrq.gov/sitemap.html" class="footer_navlink">Site Map</a> | <a href="https://www.ahrq.gov/policy/electronic/accessibility/index.html" class="footer_navlink">Accessibility</a> | <a href="https://www.ahrq.gov/policy/electronic/privacy/index.html" class="footer_navlink">Privacy
Policy</a> | <a href="https://www.ahrq.gov/policy/foia/index.html" class="footer_navlink">Freedom of Information Act</a> | <a href="https://www.ahrq.gov/policy/electronic/disclaimers/index.html" class="footer_navlink">Disclaimers</a> | <a href="http://www.hhs.gov/open/recordsandreports/plainwritingact/index.html" class="footer_navlink">Plain Writing Act</a> <br />
<a href="http://www.hhs.gov" class="footer_navlink">U.S. Department of Health &amp; Human Services</a> | <a href="http://www.whitehouse.gov" class="footer_navlink">The White House</a> | <a href="http://www.usa.gov" class="footer_navlink">USA.gov: The U.S. Government's Official Web Portal</a></p>
</div>
<div id="banner_Footeraddress"><p>Agency for Healthcare Research and Quality <img src="/images/bottom_dot.gif" alt="" /> 5600 Fishers Lane Rockville, MD 20857 <img src="/images/bottom_dot.gif" alt="" /> Telephone: (301) 427-1364</p></div>
<!-- End of Footer links section -->
</body>
</html>