Increased Lung Cancer Risk Associated With Certain Vitamin Supplements
February 29th, 2008 | by admin |A recent study published in the American Thoracic Society’s AmericanJournal of Respiratory and Critical Care Medicine reportsthat vitamin supplements do not protect against lung cancer, and may infact increase the risk of developing it.
Dr. ChristopherG. Slatore of the University of Washington and colleagues performed theanalysis by selecting a prospective cohort of 77,126 people between 50and 76 years of age who were all in the Washington State VITAL(VITamins And Lifestyle) program. The researchers analyzed the rate oflung cancer development over four years and how it correlates withcurrent and past vitamin usage, smoking, and other characteristicspertaining to demography and medical history.
Slatore writes,”Our study of supplemental multivitamins, vitamin C, vitamin E andfolate did not show any evidence for a decreased risk of lung cancer.”In addition, he notes that participants who increased intake ofsupplemental vitamin E had slightly higher risks of lung cancer.
Fromthe 77,126 people, 521 developed lung cancer; this is in linewiththe expected rate for this low-risk group. However, those who diddevelop lung cancer had a slight significant association between lungcancer and supplemental vitamin E in addition to the typicalassociationswith smoking history, family history, and age.
According to the model, a person taking 100 mg/day of vitamin E for tenyears increases the risk of lung cancer by seven percent. This is likea 28 percent increase in risk for a 400 mg/day dose for ten years.Slatore notes that this increase in risk was largely confined tocurrent smokers.
Since so many people currently or used to smoke and so many people takevitamin supplements, the study findings can benefit publichealth. ”Future studies may focus on other components offruits and vegetables that may explain the decreased risk [of cancer]that has been associated with fruits and vegetables,” notes Dr.Slatore. “Meanwhile, our results should prompt clinicians tocounsel patients that these supplements are unlikely to reduce the riskof lung cancer and may be detrimental.”
An editorial in the same journal issue by Dr. Tim Byers of theUniversity of Colorado School of Medicine suggests people want toeasily take a pill instead of eating a healthy diet, and this is whythey believe that vitamin supplements are healthy or relativelyharmless.
However, “fruits contain not only vitamins butalso many hundreds of other phytochemical compounds whose functions arenot well understood,” writes Byers. One study found a 20 percentincrease in cancer risk among people who ate the least amount of fruit,and this has led to the World Cancer Research Fund and the AmericanCancer Society to recommend two fruit servings each day.
Two servings of fruit per day “would likely lead to a reduced risk forlung cancer, as well asreduced risk of several other cancers and cardiovascular disease,”writes Dr. Byers. “However, any benefit to the population of smokersfrom increasing fruit intake to reduce cancer risk by 20 percent wouldbe more than offset if even a small proportion of smokers decided tocontinue tobacco use in favor of such a diet change.”
Long-Term Use of Supplemental Multivitamins, Vitamin C,Vitamin E, and Folate Does Not Reduce the Risk of Lung Cancer
Christopher G. Slatore, Alyson J. Littman, David H. Au, Jessie A.Satia, and Emily White
American. Journal of Respiratory and Critical Care Medicine.2008; 177: pp. 524-530.
doi:10.1164/rccm.200709-1398OC
ClickHere to View Abstract
Written by: Peter M Crosta
Copyright: Medical News Today
Stumble it!