Vitamins and lung cancer.
Lung cancer is the most common cancer in the world, and smoking is the major risk factor, accounting for about 90% of the cases. Diet has also been implicated in the development of lung cancer, although the specific nutrients remain to be elucidated. Vitamins with antioxidant activity have received much attention. beta-Carotene, the most efficient provitamin A, was found to be inversely related to the risk of lung cancer in many prospective epidemiological studies, especially in studies measuring serum concentrations of beta-carotene. The findings from controlled trials, however, contradict the hypothesis that beta-carotene could prevent lung cancer, but rather suggest increased risk of lung cancer with supplementary beta-carotene. Data from both prospective studies and a controlled trial suggest no role for vitamin E in lung carcinogenesis. Some prospective epidemiological studies suggest an inverse relationship between dietary vitamin C and the risk of lung cancer, but due to the high correlation between dietary vitamin C and vegetable and fruit intake the independent role of dietary vitamin C is difficult to estimate. Studies using prediagnostic plasma concentrations of ascorbic acid do not support the involvement of vitamin C in lung carcinogenesis, and no controlled trials of vitamin C on lung cancer have been published. Thus, supplementation with antioxidant vitamins cannot be recommended for the prevention of lung cancer. Non-smoking is the most important target in the prevention of lung cancer. High intakes of vegetables and fruits may provide additional protection and are unlikely to be harmful.
Virtamo
J
J
National Public Health Institute, Helsinki, Finland. jarmo.virtamo@ktl.fi
D001205:Ascorbic Acid / Q000008:administration & dosage; D006801:Humans; D008175:Lung Neoplasms / Q000209:etiology / Q000517:prevention & control; D012307:Risk Factors; D014801:Vitamin A / Q000008:administration & dosage; D014815:Vitamins; D019207:beta Carotene / Q000008:administration & dosage
D014815:Vitamins; D019207:beta Carotene; D014801:Vitamin A; D001205:Ascorbic Acid