Aspirin or Vitamin E does not prevent cancer
It was speculated for a long time that aspirin may prevent development of cancer. Now there is evidence to the contrary. A study which has been going on for about 12 years and involving 40,000 U.S. women has found that regular, low doses of aspirin does not prevent cancer. Also vitamin E was shown to be ineffective in preventing heart disease and cancer. Even though the report has indicated that aspirin might have a protective effect against lung cancer, this needs confirmation as per the researchers. There is no way of knowing whether if higher doses of aspirin would have protective effects. While aspirin may not work for cancer, many earlier studies have shown that this drug is effective in reducing the risk of heart attack.
"However, based on the data currently available, we do not suggest that doctors recommend low-dose aspirin therapy for primary prevention of cancer," said Nancy Cook of Brigham and Women's Hospital in Boston, chief author of the aspirin study.
These findings on aspirin and vitamin E were published in two reports in this week's Journal of the American Medical Association (JAMA). Both were based on data from the Women's Health Study, described as the largest undertaking of its kind involving the two substances.
A total of 39,876 healthy women participated in the study and these women were at least 45 years of age when it began 1992. They were followed until 2004. They were divided into four groups. Some got aspirin and an inert vitamin E placebo; others an aspirin placebo and real vitamin E; others both both aspirin and vitamin E and the last group got only placebos for both substances. The dose levels were 100 milligrams of aspirin and 600 international units of vitamin E, every other day.
While the aspirin-cancer findings were negative, earlier data from the same study group released in March found that the aspirin therapy reduced the risk of stroke by 17 percent, and in women 65 and older it did reduce the risk of heart disease, heart attack and stroke.
Eric Jacobs and Michael Thun of the American Cancer Society, commenting on the aspirin-cancer results in an editorial in the same journal, said finding a drug to prevent cancer is inherently difficult.
"It is unrealistic to expect the discovery of an agent that will produce substantial reductions in overall cancer rates in the immediate future," they added.
I-Min Lee, also of Brigham and Women's Hospital and chief author of the vitamin E report, said its findings "do not support recommending vitamin E supplementation for cardiovascular disease or cancer prevention among healthy women. At present, a healthy lifestyle and regular screening for cardiovascular health and cancer are a woman's best choices for disease prevention."
The vitamin E study did find a significant reduction in cardiovascular deaths among all the women taking the vitamin, and that women 65 and older taking vitamin E had a lower risk of heart attack, though not stroke.
"These intriguing findings deserve further study," Lee said. "But they were not part of the primary aim of the study ... additionally, previous studies of vitamin E in patients with heart disease have not shown any benefit for cardiovascular deaths. At present, we cannot recommend vitamin E for prevention against cardiovascular disease or cancer,"
Elizabeth Nabel, director of the National Heart, Lung and Blood Institute, which helped fund the study, said "We can now say that despite their initial promise, vitamin E supplements do not prevent heart attack and stroke. Instead, women should focus on well proven means of heart disease prevention."
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