Diet, smoking and lung cancer: a case-control study of 1000 cases and 1500 controls in South-West England.
We have examined the relationship between diet and lung cancer in a case-control study of 982 cases of lung cancer and 1486 population controls in south-west England in which subjects were interviewed personally about their smoking habits and their consumption of foods and supplements rich in retinol or carotene. Analyses were performed for 15 dietary variables, including intake of pre-formed retinol and carotene. There were significant associations (P< 0.01) with lung cancer risk for 13 of the variables, eight of which remained after adjustment for smoking. When the 15 variables were considered simultaneously, independent significant associations remained for 5: pre-formed retinol (increased risk), and fish liver oil, vitamin pills, carrots and tomato sauce (decreased risk). It is unlikely that all five associations represent biological effects, or that they can all be explained by residual confounding by smoking, or by biases. We conclude that there is at least one as yet unidentified factor that is causally related to lung cancer risk and of considerable importance in terms of attributable risk in this population.
ICRF/MRC/BHF Clinical Trial Service Unit & Epidemiological Studies Unit, Radcliffe Infirmary, Harkness Building, Oxford, OX2 6HE, UK.
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Darby
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Whitley
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Doll
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Key
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Silcocks
D002338:Carotenoids / Q000009:adverse effects; D016022:Case-Control Studies; D004032:Diet / Q000009:adverse effects*; D019587:Dietary Supplements / Q000009:adverse effects; D004739:England; D005260:Female; D005395:Fish Oils / Q000009:adverse effects; D006801:Humans; D008175:Lung Neoplasms / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D016017:Odds Ratio; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D012923:Social Class; D013997:Time Factors; D014801:Vitamin A / Q000009:adverse effects; D014815:Vitamins / Q000009:adverse effects
D005395:Fish Oils; D014815:Vitamins; D014801:Vitamin A; D002338:Carotenoids