NEW YORK, Oct 19 (Reuters Health) -- High levels of alpha-tocopherol, a form of vitamin E, in the blood appear to reduce the risk of developing lung cancer in smokers by about 20%, according to a report released Tuesday.
However, the researchers say that more study is needed to determine if taking supplements of the vitamin can reduce cancer risk.
"The results of this study showed that serum (blood) levels of vitamin E taken at the beginning of the study was associated with reduced lung cancer." lead study author Dr. Karen Woodson told Reuters Health. The research is published in the October 20th edition of the Journal of the National Cancer Institute.
Woodson, of the National Cancer Institute in Bethesda, Maryland, and colleagues there and at the National Public Health Institute in Helsinki, Finland utilized data from a cancer prevention study in Finland to identify vitamin E levels in 1,144 men with lung cancer.
The researchers report that high alpha-tocopherol serum levels at the beginning of the study, high dietary intake of alpha-tocopherol and high dietary intake of vitamin E were associated with a lower lung cancer risk.
The researchers attribute the decrease in cancer to vitamin E's antioxidant properties and anticancer properties.
Woodson and colleagues report that the men most likely to experience a benefit from high serum levels of alpha-tocopherol included those younger than 60, men who had smoked for less than 40 years and men who took vitamin E supplements containing alpha-tocopherol during the study.
The authors add that the findings "reinforce the importance of adequate vitamin E status to lung cancer risk, particularly among smokers," and that "supplementation may have provided the higher dosages possibly required for inhibition of" the cell pathways that lead to cancer.
Despite these results, Woodson said in an interview with Reuters Health that "the National Cancer Institute has never recommended taking supplements." She explained that "other nutrients like you would get in a balanced diet may be likely to be needed as well for a number of reasons. Further, I would like to stress that the men who went on to take supplements didn't seem to have fewer lung cancers so we can't recommend that. We recommend quitting smoking."
She added that "we would recommend eating a well-balanced diet in line with the Dietary Guidelines for Americans -- lots of fruits, vegetables, and whole grains, fat in the 30% or less category."
"While it is tempting, based on the present data, to speculate that the administration of greater quantities of alpha-tocopherol... might have produced a substantial reduction in lung cancer incidence... only future studies... can shed light on this question," the team concludes.
The authors also call for further research to see if the same relationship between vitamin E and lung cancer holds for women. Woodson told Reuters Health that she expects to see similar results in women.
"The biology of lung cancer is thought to be essentially the same between men and women; (lung) cancer in both is thought to be due mainly to smoking," she commented.
