The potential beneficial effects ? calculated by analyzing data from 38,597 women participating in the Women's Health Study (WHS) ? were observed in both smokers and non-smokers, according to findings published in the journal Thorax.
COPD can cause coughing that produces large amounts of mucus (a slimy substance), wheezing, shortness of breath, chest tightness, and other symptoms, with cigarette smoking the leading cause.
According to the US National Institutes of Health, COPD is a major cause of disability, and it is the fourth leading cause of death in the US, with over 12 million people currently diagnosed with the disease.
The oxidant/antioxidant balance in lung tissue is hypothesized to contribute to chronic obstructive pulmonary disease (COPD) risk, said the researchers, and they noted that observational studies consistently report high antioxidant status associated with lower risk of COPD and asthma.
Led by Anne Hermetet Agler from Cornell University's Division of Nutritional Sciences, the researchers analyzed data from the WHS, a randomized double-blind placebo-controlled trial that ended in 2004. Women received either vitamin E supplements at a dose of 600 IU every other day plus aspirin at a dose of 100 mg every other day, or placebo.
Over the course of 10 years of study, the researchers documents 760 new cases of chronic lung disease in the recipients of vitamin E compared with 846 cases in the recipients of the placebo.
This was equivalent to a 10 percent decrease in the risk of developing chronic lung disease, said the researchers, and this was not affected by the smoking status of the individuals.
There are eight forms of vitamin E: four tocopherols (alpha, beta, gamma, delta) and four tocotrienols (alpha, beta, gamma, delta). Alpha-tocopherol is the main source found in supplements and in the European diet, while gamma-tocopherol is the most common form in the American diet.
Tocotrienols are only minor components in plants, although several sources with relatively high levels include palm oil as well as cereal grains and rice bran.
Volume 66, Issue 4, Pages 320-325
?Randomised vitamin E supplementation and risk of chronic lung disease in the Women's Health Study?
Authors: A.H. Agler, T. Kurth, J.M Gaziano, J.E. Buring,P.A. Cassano