"To explain the meaning of this parameter," says Dr. Pinchuk, "consider a participant who was healthy during the first 10 out of 20 years of the study, but then suffered a stroke and became dependent on others throughout the following 10 years. The QALY during the first 10 years of healthy life is 10, but after the stroke the quality of life is only half of what this person had before. Therefore, the second decade is considered the equivalent of merely 5 years of healthy life and in sum a person's QALY is 15.
The researchers examined data from more than 300,000 subjects in the US, Europe and Israel. "Our major finding," says Dr. Pinchuk, "was that the average quality-adjusted life years (QALY) of Vitamin E- supplemented individuals was 0.30 less than that of untreated people. This, of course, does not mean that everybody consuming Vitamin E shortens their life by almost 4 months. But on average, the quality-adjusted longevity is lower for vitamin-treated people. This says something significant."
Overturning earlier studies
In the BioFactors article, the TAU researchers defined "the real challenge as being able to identify who is likely to benefit taking Vitamin E." They also explored the first hypothesis of the oxidative theory of atherosclerosis published more than 20 years ago, which was the basis for the widespread use of antioxidants today. At first, this hypothesis raised great enthusiasm that anti-oxidants like Vitamins E and C and flavonoids could be used to prevent disease or its progression. In this respect, the new findings are very disappointing.
"We've now concluded that going to the grocery or to a health food store to buy Vitamin E supplements, for the most part, won't do you good. In some cases it can do harm," says Dr. Pinchuk. "A doctor wouldn't prescribe anti-hypertension drugs to the whole population, only to those with low blood pressure. It seems this is true
|Contact: George Hunka|
American Friends of Tel Aviv University