|
Last Updated: Apr 16, 2008 - 5:52:06 PM |
SUNDAY March 23, 2008 (foodconsumer.org) -- Taking vitamin E supplements for a long term may moderately increase risk of lung cancer, according to a new study published in the American Journal of Respiratory and Critical Care Medicine.
The study of 77,000 people found taking 400 milligrams per day for a long term were associated with a 28% increased cancer risk and the association was particularly strong among smokers.
The study is not a trial. The results showed merely the association between intake of vitamin E supplements and risk of lung cancer, cautioned a scientist affiliated with foodconsumer.org who was not part of the research team. Other risk factors also may be responsible for the increased cancer risk.
For the study, Dr Christopher Slatore of the University of Washington in Seattle and colleagues followed people aged 50 to 76 for four years for their intakes of vitamin C, folic acid and vitamin E supplements and they recorded 521 cases of lung cancer.
Smoking, family history, age, and supplementation of vitamin E were linked to increased risk of development of lung cancer while use of vitamin C or folic acid was not, the study found.
The researchers found the risk would be increased by 7% over a decade for those who used 100 milligrams per day. The increase in the cancer risk was higher among smokers. If the daily dose was 400 milligrams, then the risk could be increased to 28 %.
Vitamin E is often used as antioxidants and believed to be able to neutralize free radicals that would otherwise injure cells and lead to development of cancer.
But the researchers explained that vitamin E may also act as a pro-oxidant, meaning that it can actually cause oxidation and promote damage to cells.
Laboratory studies have earlier showed that alpha-tocopheryl succinate, a vitamin E ester can inhibit proliferation of cancer cells and induce apoptosis in a number of cancer cell lines.
Animal model studies also showed that administration of this vitamin E ester by injection may inhibit tumor growth. But it's not reported that any vitamin E could help stop cancer in vivo.
Lung cancer is one of the most common deadly cancers. In the United States, 215,020 people are expected to be diagnosed with this disease and 161,840 will die from the disease and complications in 2008, according to The National Cancer Institute.
Vitamin E is found in olive oil, soybean oil, corn oil, canola oil, safflower oil, sunflower oil, almonds, hazelnuts, peanuts, spinach and avocado.
© 2004-2008 by foodconsumer.org unless otherwise specified
Top of Page
|
