Lung cancer happens when the cells in the lungs become abnormal, forming more cells in an uncontrolled way. In the United States, more people die from lung cancer than any other type of cancer, according to the Medline Plus. Several studies have suggested that foods rich in antioxidants may reduce the risk of developing lung cancer, however, you should consult a doctor or a dietitian for specific advice.
Antioxidant Vitamins
Even though numerous studies on the anti-cancer activity of antioxidant vitamins and carotenoids have turned up positive results, there have also been studies with no effects. In spite of initial optimism, it is not clear whether taking provitamin A carotenoids offer significant protective effects against lung cancer, according to a 2006 study published in the journal "Current Pharmaceutical Design". This is an active area of research with much work needed to resolve this issue. On the other hand, vitamins C and E exhibited potential anticarcinogenic activities in several studies, says A. Ruano-Ravina of University of Santiago de Compostela in Spain. However, the mechanisms responsible for the inhibitory effects of these antioxidant vitamins are not yet clear.
Reactive Oxygen Species
Evidence suggests that antioxidants found in fruits and vegetables and in many other foods may reduce the risk of lung cancer, according to the "American Journal of Epidemiology." Antioxidants scavenge free radicals, or highly reactive oxygen molecules, which are produced by oxidation reactions in your body. Free radicals travel through the cell and react with important cellular components such as DNA, protein and cell membrane, causing cellular damage and cell death. Such damage is believed to contribute to diseases like cancer.
Carcinogens
In a 2000 study published in "Journal of the National Cancer Institute", S.P. Murphy and colleagues at the University of Hawaii reported that the lung cancer inhibitory effect of flavonoids, a special group of antioxidants, is due to their specificity and carefully regulated expression in cytochrome P450 enzymes -- a large family of constitutive and inducible heme-containing enzymes that play an important role in the metabolism of a wide variety of carcinogens. By blocking the expression and activity of P450 enzymes, flavonoids could decrease the carcinogenicity of many significant endogenous carcinogens.
Oxidative Damage
Human lung tissues are vulnerable to oxidative DNA damage. The risk of lung cancer is lower in men who consume diets high in fruits, vegetables, carotenoid- and polyphenolic-rich products, according to the University of Maryland Medical Center. These foods contain higher levels of antioxidants such as flavonoids, beta-carotene, vitamin E and vitamin C which decrease free radical attack on DNA and thus provide protection against mutations that cause cancer.
References
- "Current Pharmaceutical Design": Antioxidant Vitamins and Risk of Lung Cancer; A. Ruano-Ravina; 2006
- University of Maryland Medical Center: Non-small cell lung cancer - Lifestyle Changes; Harvey Simon; July 23, 2009
- "Journal of the National Institute": Intake of Flavonoids and Lung Cancer; S.P. Murphy; Jan. 2000
- "American Journal of Epidemiology"; Dietary Flavonoids and the Risk of Lung Cancer and Other Malignant Neoplasms; Paul Knekt; April 7, 1997
- MedlinePlus: Lung Cancer
