Folate may protect against hemorrhagic stroke
In addition to its effects on homocysteine, an amino acid linked to Heart disease, folate may protect against a certain type of Stroke. Specifically, investigators found that Folate, a B vitamin found in green leafy vegetables, fruits and dried beans, appears to lower the risk of Hemorrhagic strokes, strokes caused by bleeding in the brain.
“Folate metabolism has been implicated in Stroke,” Dr. Bethany Van Guelpen, of Umea University, Sweden, and colleague write in the medical journal Stroke. “However, the possibility of a role for Folate and Vitamin B12, independent of their effect on homocysteine status, remains to be explored.”
The researchers examined blood and dietary levels of folate and Vitamin B12 in 62 patients who had a Hemorrhagic stroke and 334 who had an ischemic stroke, which are the result of blocked blood flow in the brain.
Blood levels of folate were inversely associated with the risk of Hemorrhagic stroke. The association remained after accounting for the effects of conventional risk factors.
No association was observed between blood levels of vitamin B12 and either type of stroke.
The investigators report that dietary folate was not associated with the risk of ischemic stroke, but it was inversely associated with the risk of Hemorrhagic stroke. Dietary vitamin B12 was not significantly related to either stroke type.
Van Guelpen’s team notes that the lack of any association with ischemic stroke was unexpected.
They point out that the food in Sweden is not fortified with folate and intake of fruit and vegetables is relatively low, so folate levels might not have been high enough to show a protective effect against ischemic stroke.
SOURCE: Stroke, July 2005.
Revision date: June 22, 2011
Last revised: by Andrew G. Epstein, M.D.