title: Polyunsaturated fatty acid intake and risk of lung cancer: a meta-analysis of prospective studies.
abstract: BACKGROUND
  Studies have reported inconsistent results for the existence of an association between polyunsaturated fatty acid (PUFA) intake and risk of lung cancer. The purpose of this study is to summarize the evidence regarding this relationship using a dose response meta-analytic approach.
  
  
  RESULTS
  We searched the PubMed, EmBase, and Cochrane Library electronic databases for related articles published through July 2013. Only prospective studies that reported effect estimates with 95% confidence intervals (CIs) of lung cancer incidence for greater than 2 categories of PUFA intake were included. We did random-effects meta-analyses of study-specific incremental estimates to determine the risk of lung cancer associated with a 5 g per day increase in PUFA intake. Overall, we included 8 prospective cohort studies reporting data on 1,268,442 individuals. High PUFA intake had little or no effect on lung cancer risk (risk ratio [RR], 0.91; 95% CI, 0.78-1.06; P = 0.230). Furthermore, the dose-response meta-analysis also suggested that a 5 g per day increase in PUFA has no significant effect on the risk of lung cancer (RR, 0.98; 95%CI: 0.96-1.01; P = 0.142). Finally, the findings of dose response curve suggested that PUFA intake of up to 15 g/d seemed to increase the risk of lung cancer. Furthermore, PUFA intake greater than 15 g/d was associated with a small beneficial effect and borderline statistical significance. Subgroup analyses for 5 g per day increment in PUFA indicated that the protective effect of PUFA was more evident in women (RR, 0.94; 95% CI, 0.87-1.01; P = 0.095) than in men (RR, 1.00; 95% CI, 0.98-1.02; P = 0.784).
  
  
  CONCLUSIONS
  Our study indicated that PUFA intake had little or no effect on lung cancer risk. PUFA intake might play an important role in lung cancer prevention in women.
authors.affiliation: Department of Oncology, Shanghai Seventh People's Hospital, Shanghai, China.
authors.forename: Yu-Fei
authors.initials: YF
authors.lastname: Zhang
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, China.
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Yu
authors.affiliation: Department of Oncology, Shanghai Seventh People's Hospital, Shanghai, China.
authors.forename: Hong-Fang
authors.initials: HF
authors.lastname: Gao
authors.affiliation: Department of Rehabilitation Institute, Shanghai Seventh People's Hospital, Shanghai, China.
authors.forename: Yu-Hao
authors.initials: YH
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004435:Eating / Q000502:physiology*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated