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Effects of Omega-3 Fatty Acids on Cancer Risk

Catherine H. MacLean, Sydne Jennifer Newberry, Walter Mojica, Puja P. Khanna, Amalia M. Issa, Marika J Suttorp, Yee-Wee Lim, Shana Traina et al.

JAMA, 2006

486 citations

Abstract

CONTEXT: Omega-3 fatty acids are purported to reduce the risk of cancer. Studies have reported mixed results. OBJECTIVE: To synthesize published and unpublished evidence to determine estimates of the effect of omega-3 fatty acids on cancer risk in prospective cohort studies. DATA SOURCES: Articles published from 1966 to October 2005 identified through MEDLINE, PREMEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and CAB Health; unpublished literature sought through letters to experts in the neutraceutical industry. STUDY SELECTION: A total of 38 articles with a description of effects of consumption of omega-3 fatty acids on tumor incidence, prospective cohort study design, human study population; and description of effect of omega-3 among groups with different levels of exposure in the cohort were included. Two reviewers independently reviewed articles using structured abstraction forms; disagreements were resolved by consensus. DATA EXTRACTION: Two reviewers independently abstracted detailed data about the incidence of cancer, the type of cancer, the number and characteristics of the patients, details on the exposure to omega-3 fatty acids, and the elapsed time between the intervention and outcome measurements. Data about the methodological quality of the study were also abstracted. DATA SYNTHESIS: Across 20 cohorts from 7 countries for 11 different types of cancer and using up to 6 different ways to categorize omega-3 fatty acid consumption, 65 estimates of…

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