Wednesday, March 19, 2008

Health Risk of Vitamine E Supplements

Supplemental Vitamin E May Increase Heart Failure Risk

WHS: Women's Heath Study -- Aspirin and Vitamin E for the Primary Prevention of Cardiovascular Disease
qualified success for aspirin in cardioprevention, but no benefit associated with the use of vitamin E.

Meta-analysis Results Suggest High-Dose Vitamin E Increases All-Cause Mortality
"At 400 IUs, which is the most common marketed dose, the risk of dying is about 10% higher than risk among people not taking the vitamin."
Dr.Gibbons, who served as chair of the scientific program committee at the meeting, said he has been urging his patients to stop taking vitamin E for years. Dr. Gibbons said that cardiovascular disease prevention guidelines from "vitamin E is ‘not recommended'. It doesn't get clearer than that — don't take it."

Dr. Miller said there are several theories about why vitamin E increases risk. One theory is that it increases bleeding risk, which would increase the risk of hemorrhagic stroke, while another theory suggests that at high doses vitamin E stops working like an antioxidant that mops up free radicals that attack cells that line blood vessels and instead becomes a prooxidant and actually promotes the production of free radicals.

Still another scenario suggests that high-doses of vitamin E tend to destroy other fat-soluble antioxidants, which disrupts the body's natural antioxidant protection system.

Antioxidant Vitamins May Increase Mortality

March 1, 2007 — The largest analysis of data on antioxidant vitamins ever conducted has shown that beta-carotene, vitamin A, and vitamin E probably increase mortality. Two other antioxidant substances — vitamin C and selenium — had no effect on mortality.

"Vitamin A and beta-carotene seem to have a dose-related effect, with mortality increasing as doses increase, whereas vitamin E does not appear to have a dose-related effect, with all doses associated with increased mortality."

antioxidant vitamins could actually also have prooxidant effects. "We don't know exactly how they are doing harm but rather than preventing cardiovascular disease and cancer, they actually seem to be accelerating these conditions."

Multivitamins Do Not Reduce Risk for Lung Cancer, and Vitamin E May Raise It

February 29, 2008 — The long-term use of supplemental multivitamins does not reduce the risk of developing lung cancer, and high doses of vitamin E may even raise the risk, particularly in smokers.
Although consuming higher amounts of fruits and vegetables can reduce the risk for lung cancer, multivitamins and supplements have generally not demonstrated a benefit in reducing this risk.

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