Vitamin E Supplements May Increase and Decrease Stroke Risk
Do vitamin E supplements increase or decrease your risk of stroke? Both, says a new study, depending in the type of stroke—hemorrhagic or ischemic—to which you are referring. The increased risk in hemorrhagic stroke, however, is more significant than the small reduction in risk from ischemic stroke.
Vitamin E supplements have two effects on stroke risk
The new study, published in the British Medical Journal, reported on the analysis of nearly 120,000 people from nine different trials: half took vitamin E supplements (range of dose, 50 to 500 mg) and half took placebo. Overall, the risk of hemorrhagic stroke increased 22 percent among individuals who took the supplement when compared with placebo.
The researchers, headed by Markus Schurks of Harvard Medical School, also found that vitamin E supplements reduced the risk of ischemic stroke by 10 percent. According to the American Heart Association, the majority (87%) of strokes are ischemic, which means an artery to the brain is blocked. The remaining 13 percent are comprised of 10 percent intracerebral hemorrhagic and 3 percent subarachnoid hemorrhagic strokes. A hemorrhagic stroke occurs when a weakened blood vessel in or on the surface of the brain bursts.
Although both types of stroke can be fatal, ischemic stroke tends to have less severe consequences. Schurks pointed out that the increased risk of hemorrhagic stroke equaled only one additional such incident occurring for every 1,250 people who took vitamin E. The researchers also noted that steps such as lowering cholesterol and blood pressure have a greater impact on reducing the risk of ischemic stroke than taking vitamin E.
The American Heart Association Stroke Update 2010 notes that the prevalence (number of people with the condition) of stroke is 6.4 million, encompassing 2.5 million men and 3.9 million women. The Update reports that 795,000 new or recurrent strokes occurred in 2006 (year with the latest available data), affecting 425,000 women and 370,000 men, and causing 137,000 deaths (82,600 women, 54,500 men).
So while this study indicates that vitamin E supplements can both increase and decrease the risk of stroke, depending on the type of stroke, the bottom line from the authors is that “Given the relatively small risk reduction of ischemic stroke and the generally more severe outcome of hemorrhagic stroke, indiscriminate widespread use of vitamin E should be cautioned against.” Before starting vitamin E supplementation, consult a knowledgeable healthcare professional.
American Heart Association
Schurks M et al. British Medical Journal 2010; 341:c5702