Vitamin C to Reduce Stroke Risk

I'm passing this along from Agora Lifestyles Newletter

According to the findings of a large European-based study, increased
blood levels of vitamin C may reduce the risk of stroke by as much as
42 per cent.

Increased levels of the vitamin, associated with increased intake of
fruit and vegetables, were found to offer significant cardiovascular
benefits among the 20,649 men and women taking part in the European
Prospective Investigation into Cancer.

The researchers, led by Phyo Myint from the University of Cambridge,
claim that blood levels of the vitamin could be used as a biological
marker of lifestyle used to identify people at high risk of stroke.

Myint said: "An intriguing possibility is that the plasma vitamin C
concentration is a good marker of a wider range of health behaviours,
such as fruit and vegetable consumption, that may be protective against
stroke. It is also plausible that vitamin C may biochemically affect
stroke risk."

Strokes occur when blood clots or an artery bursts in the brain and
interrupts the blood supply to a part of the brain. It is the leading
cause of disability and the third leading cause of death in Europe and
the US.

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Assessing the results
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Myint and his fellow researchers followed the subjects for 9.5 years
and documented 448 strokes during this time. The subjects completed a
health and lifestyle questionnaire at the start of the study, and blood
samples were taken to measure vitamin C levels.

The highest average blood levels of vitamin C (greater than 66
micromoles per litre) were associated with a 42 per cent lower risk of
stroke, compared to the lowest average blood levels (less than 41
micromoles per litre), after adjusting the results for potentially
confounding factors such as age, sex, smoking habits, alcohol
consumption, blood pressure, cholesterol levels, BMI, physical
activity, and use of supplements.

When the Cambridge researchers excluded participants who consumed
vitamin C-containing supplements the results were the same, indicating
that the benefits could have been from vitamin C-rich foods, such as
fruit and vegetables.

"We believe that these findings are of interest for several reasons,"
stated the researchers. "First, the strong inverse association between
plasma vitamin C and stroke suggests that plasma vitamin C is likely to
be a good biomarker of whatever causal factors affect stroke risk, most
plausibly the dietary intake of plant foods.

"Second, irrespective of any causal associations, plasma vitamin C
appears to be a good predictive risk indicator of stroke, independent
of known risk factors such as age, BP, smoking, lipids, diabetes, and
BMI.

"Given that about half of the risk of stroke is unexplained by
conventional cardiovascular disease risk factors and that the
predictive validity of traditional cardiovascular disease risk factors
appears to diminish with age, risk markers that may help to identify
those persons at greatest risk of stroke for targeted preventive
interventions with established therapies, such as BP reduction, may be
of interest."
Source: American Journal of Clinical Nutrition, January 2008, Volume
87, Pages 64-69