According to the National Cancer Institute, more than 220,000 people develop lung cancer annually in the United States. A disease that is almost always fatal, lung cancer accounts for almost 20 percent of all cancer deaths in the United States. Lung cancer preferentially affects men from higher-income countries. A diet high in fruits and vegetables, consumption of selenium, and regular physical activity reduce your risk of developing lung cancer, states the American Institute for Cancer Research.
Beta-Carotene
As a pro-vitamin A carotenoid, beta-carotene may be converted to vitamin A in the body which is essential for proper vision, immune function and normal cellular function. Get your beta-carotene from carrots, sweet potatoes, and green leafy vegetables. Absorption of beta-carotene from your diet requires a little bit of fat, so use a low-fat dressing on salads or consume other foods containing fat when you eat your beta-carotene rich foods.
Dietay Beta-Carotene
Epidemiological studies suggest that increased intake or blood levels of beta-carotene decrease risk of lung cancer, states a review by Goralczyk. The Linus Pauling Institute at the Oregon State University says that numerous large-population based studies suggest that diets high in carotenoids reduce lung cancer incidence. Observational studies also found beta-carotene from foods decreased lung cancer incidence. In contrast, a 10 year study of more than 120,000 men and women reported that beta-carotene did not affect lung cancer risk. However, additional analysis suggested that higher total carotenoid intake, including alpha-carotene, lutein and lycopene, reduced lung cancer incidence.
Supplemental Beta-Carotene in Smokers
A review by Goralczyk found long-term, high dose beta-carotene supplementation increased lung cancer rates in smokers. Lung cancer risk also increase in people consuming beta-carotene supplements who worked with asbestos, a known lung irritant. The Alpha-Tocopherol Beta-Carotene study, the Beta-Carotene and Retinol Efficacy Trial, the Antioxidant Polyp Prevention trial, and the E3N study found that increased risk with beta-carotene supplementation correlated to smoking or lung irritant status. Furthermore, in studies with a low number of smokers, such as the the Physician Health Study and the Linxian Trial, beta-carotene supplements did not promote lung cancer. Veeramachaneni and colleagues hypothesize that the stress caused in the lungs from smoking changed the functionality of beta-carotene. Normally considered an antioxidant, beta-carotene became unstable in such a harsh lung environment.
American Institute for Cancer Research
A review of all human-based research examined the impact of diet, lifestyle modification, and physical activity on lung cancer risk. The Expert Panel, compiled by the American Institute for Cancer Research, concluded there is substantial scientific evidence to suggest that beta-carotene supplements significantly increase your risk of developing lung cancer if you smoke. In contrast, they concluded that foods containing carotenoids, such as beta-carotene, significantly reduce your risk of lung cancer. The split recommendations depend on your smoking status and your source of beta-carotene, whether it is from the diet or from supplements.
References
- National Cancer Institute: SEER Stat Fact Sheets: Lung and Bronchus
- Oregon State University: Micronutrient Information Center: Carotenoids
- "Nutrition and Cancer"; Beta-Carotene and Lung Cancer in Smokers: Review of Hypotheses and Status of Research; R Goralczyk; Nov. 2009
- "Frontiers in Bioscience"; Carotenoids and Lung Cancer Prevention; S Veeramachaneni, XD Wang; Jun. 2009
- "Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective"; American Institute for Cancer Research; 2007
