{"id":382,"date":"2017-08-04T18:16:03","date_gmt":"2017-08-04T16:16:03","guid":{"rendered":"https:\/\/www.pharmarte.com\/?p=382"},"modified":"2017-08-04T18:16:03","modified_gmt":"2017-08-04T16:16:03","slug":"effects-of-folic-acid-supplementation-on-overall-and-site-specific-cancer-incidenceduring-the-randomised-trials-meta-analyses-of-data-on-50000-individuals","status":"publish","type":"post","link":"https:\/\/www.pharmarte.com\/en\/effects-of-folic-acid-supplementation-on-overall-and-site-specific-cancer-incidenceduring-the-randomised-trials-meta-analyses-of-data-on-50000-individuals\/","title":{"rendered":"Effects of folic acid supplementation on overall and site-specific cancer incidenceduring the randomised trials: meta-analyses of data on 50,000 individuals."},"content":{"rendered":"<div id=\"container\" class=\"hfeed\">\n<div id=\"wrapper\" class=\"clearfix\">\n<div id=\"content\" class=\"grid col-620\">\n<div id=\"post-1403\" class=\"post-1403 post type-post status-publish format-standard hentry category-mthfr-prevent-plus\">\n<div class=\"post-entry\">\n<p>Vollset SE<sup>1<\/sup>\u00a0et al.<\/p>\n<h3>Abstract<\/h3>\n<h4>BACKGROUND:<\/h4>\n<p>Some countries fortify flour with\u00a0folic\u00a0acid\u00a0to prevent neural tube defects but others do not, partly because of concerns about possible\u00a0cancer\u00a0risks. We aimed to assess any\u00a0effects\u00a0on\u00a0site-specific\u00a0cancer\u00a0rates in therandomised\u00a0trials\u00a0of\u00a0folic\u00a0acid\u00a0supplementation, at doses higher than those from fortification.<\/p>\n<h4>METHODS:<\/h4>\n<p>In these\u00a0meta-analyses, we sought all\u00a0trials\u00a0completed before 2011 that compared\u00a0folic\u00a0acid\u00a0versus placebo, had scheduled treatment duration at least 1 year, included at least 500 participants, and recorded\u00a0data\u00a0oncancer\u00a0incidence. We obtained individual participant datasets that included 49,621 participants in all 13 such\u00a0trials(ten\u00a0trials\u00a0of\u00a0folic\u00a0acid\u00a0for prevention of cardiovascular disease [n=46,969] and three\u00a0trials\u00a0in patients with colorectal adenoma [n=2652]). All these\u00a0trials\u00a0were evenly\u00a0randomised. The main outcome was incident\u00a0cancer\u00a0(ignoring non-melanoma skin\u00a0cancer) during the scheduled treatment period (among participants who were still free of\u00a0cancer). We compared those allocated\u00a0folic\u00a0acid\u00a0with those allocated placebo, and used log-rank analyses to calculate the\u00a0cancerincidence\u00a0rate ratio (RR).<\/p>\n<h4>FINDINGS:<\/h4>\n<p>During a weighted average scheduled treatment duration of 5\u0e01\u0e042 years, allocation to\u00a0folic\u00a0acid\u00a0quadrupled plasma concentrations of\u00a0folic\u00a0acid\u00a0(57\u0e01\u0e043 nmol\/L for the\u00a0folic\u00a0acid\u00a0groups vs 13\u0e01\u0e045 nmol\/L for the placebo groups), but had no significant effect on overall\u00a0cancer\u00a0incidence\u00a0(1904 cancers in the\u00a0folic\u00a0acid\u00a0groups vs 1809 cancers in the placebo groups, RR 1\u0e01\u0e0406, 95% CI 0\u0e01\u0e0499\u0e08C1\u0e01\u0e0413, p=0\u0e01\u0e0410). There was no trend towards greater effect with longer treatment. There was no significant heterogeneity between the results of the 13 individual\u00a0trials\u00a0(p=0\u0e01\u0e0423), or between the two overall results in the cadiovascular prevention\u00a0trials\u00a0and the adenoma\u00a0trials\u00a0(p=0\u0e01\u0e0413). Moreover, there was no significant effect of\u00a0folic\u00a0acid\u00a0supplementation on the\u00a0incidence\u00a0of\u00a0cancer\u00a0of the large intestine, prostate, lung, breast, or any other specific site.<\/p>\n<h4>INTERPRETATION:<\/h4>\n<p>Folic\u00a0acid\u00a0supplementation does not substantially increase or decrease\u00a0incidence\u00a0of\u00a0site-specificcancer\u00a0during the first 5 years of treatment. Fortification of flour and other cereal products involves doses of\u00a0folic\u00a0acidthat are, on average, an order of magnitude smaller than the doses used in these\u00a0trials<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Vollset SE1\u00a0et al. Abstract BACKGROUND: Some countries fortify flour with\u00a0folic\u00a0acid\u00a0to prevent neural tube defects but others do not, partly because of concerns about possible\u00a0cancer\u00a0risks. We aimed<span class=\"excerpt-hellip\"> [\u2026]<\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42],"tags":[],"class_list":["post-382","post","type-post","status-publish","format-standard","hentry","category-bibliografia-mthfr-prevent-plus"],"_links":{"self":[{"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/posts\/382","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/comments?post=382"}],"version-history":[{"count":1,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/posts\/382\/revisions"}],"predecessor-version":[{"id":383,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/posts\/382\/revisions\/383"}],"wp:attachment":[{"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/media?parent=382"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/categories?post=382"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.pharmarte.com\/en\/wp-json\/wp\/v2\/tags?post=382"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}