Your lungs are an important part of your respiratory system. They transport oxygen to your organs and tissues and carry waste gases like carbon dioxide away from them. Cancer, which is uncontrolled abnormal cell growth, can affect your lungs. Although the exact mechanisms are unknown, the trace mineral selenium may have protective effects against lung cancer. Consult your doctor before increasing your selenium intake or taking selenium supplements.
Selenium
Selenium is a trace mineral, which means that your body requires only a small amount. The recommended dietary selenium intake is 55 mcg a day, if you are 19 or older. Selenium is needed to make selenoproteins, which are antioxidant enzymes. Antioxidants help prevent free radical cellular damage. Free radicals may contribute to the development of cancer and heart disease. Free radicals are natural oxygen-uptake byproducts. However, they are unstable because they have at least one unpaired electron. They can damage your cells as they go around stealing electrons in an effort to pair up.
Selenium Status
Low selenium status is associated with lung cancer risk, according to a study published in the November 1998 issue of the "American Journal of Epidemiology." The study found an increased lung cancer incidence in previously healthy individuals with low selenium status. The study found that the lower your selenium levels are, the higher your lung cancer risk. The study, conducted by the National Public Health Institute in Finland, also found an increased risk in smokers who have low selenium status.
Selenoprotein Variant Risk
Although clinical data suggest that low selenium status increases your risk of lung cancer, it is important to consult your doctor before increasing your selenium intake. Increasing selenium intake is associated with an increased lung cancer risk in smokers with a genetic variant in the way selenium is metabolized, according to a study published in the September 2008 issue of the "European Journal of Nutrition." The study found that a mutation in the way your body makes selenoproteins results in a different response that increases your lung cancer risk. Individuals with this variant do not benefit from increased selenium intake. However, individuals without this variant do, according to the study.
Precautions
Clinical data suggest that increased selenium intake is associated with lower lung cancer risk in some and higher risk in others. Tuna, turkey, beef, cod and brazil nuts are rich sources of selenium. Selenium is also available as a dietary supplement. Consult your doctor before taking selenium supplements, as all supplements have the capacity to cause side effects or interact with other medications.
References
- PubMed Health; Lung Cancer; David Ziev, MD, MHA, and Yi-Bin Chen, MD; September 2010
- Office of Dietary Supplements, National Institutes of Health; Dietary Supplement Fact Sheet: Selenium; November 2009
- "American Journal of Epidemiology"; Is Low Selenium Status a Risk Factor for Lung Cancer?; P. Knekt, et al.; November 1998
- "European Journal of Nutrition"; Lung Cancer Risk Associated with Selenium Status Is Modified in Smoking Individuals by Sep15 Polymorphism; E. Jablonska, et al.; February 2008
