Review: antioxidant supplementation does not reduce gastrointestinal cancer
Q Do antioxidant supplements reduce the risk of gastrointestinal cancer?
Cochrane controlled trial registers for 4 gastrointestinal disease groups, Cochrane Central Register of Controlled Trials (2003, Issue 1), Medline (1966 to February 2003), EMBASE/Excerpta Medica (1985 to February 2003), LILACS (1982 to February 2003), Science Citation Index Expanded (1945 to February 2003), Chinese Biomedical Database (1978 to March 2003), reference lists of retrieved studies, and manufacturers of antioxidant supplements.
Study selection and assessment:
randomised controlled trials (RCTs) comparing antioxidant supplementation (β carotene; vitamins A, C, and E; and selenium, separately or in combination) with placebo in patients mainly with non-gastrointestinal diseases at high risk of gastrointestinal cancer. Methodological quality of individual studies was assessed based on allocation sequence, allocation concealment, blinding, and follow up.
gastrointestinal cancer (oesophageal, gastric, colorectal, pancreatic, or liver) and all cause mortality.