title: Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies.
abstract: Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk.
authors.affiliation: Harvard School of Public Health, Department of Nutrition, Boston, Massachusetts, USA.
authors.forename: Satu
authors.initials: S
authors.lastname: Männistö
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Smith-Warner
authors.forename: Donna
authors.initials: D
authors.lastname: Spiegelman
authors.forename: Demetrius
authors.initials: D
authors.lastname: Albanes
authors.forename: Kristin
authors.initials: K
authors.lastname: Anderson
authors.forename: Piet A
authors.initials: PA
authors.lastname: van den Brandt
authors.forename: James R
authors.initials: JR
authors.lastname: Cerhan
authors.forename: Graham
authors.initials: G
authors.lastname: Colditz
authors.forename: Diane
authors.initials: D
authors.lastname: Feskanich
authors.forename: Jo L
authors.initials: JL
authors.lastname: Freudenheim
authors.forename: Edward
authors.initials: E
authors.lastname: Giovannucci
authors.forename: R Alexandra
authors.initials: RA
authors.lastname: Goldbohm
authors.forename: Saxon
authors.initials: S
authors.lastname: Graham
authors.forename: Anthony B
authors.initials: AB
authors.lastname: Miller
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Rohan
authors.forename: Jarmo
authors.initials: J
authors.lastname: Virtamo
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.forename: David J
authors.initials: DJ
authors.lastname: Hunter
mesh_terms: D002338:Carotenoids / Q000008:administration & dosage / Q000009:adverse effects*; D015331:Cohort Studies; D016001:Confidence Intervals; D004032:Diet; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D008297:Male; D009656:North America / Q000453:epidemiology; D012042:Registries; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D011795:Surveys and Questionnaires
chemical_list: D002338:Carotenoids