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Te weinig vitamine C vergroot kans op beroerte.*
Mensen die te weinig vitamine C krijgen per dag lopen een groter risico op een beroerte, zo blijkt uit nieuw onderzoek in Finland. Dr. Sudhir Kurl van de Universiteit van Kuopio ontdekte dat mannen van middelbare leeftijd die relatief lage spiegels vitamine C in hun bloed hadden een tweemaal zo grote kans hadden op een beroerte.dan mannen met een hogere spiegel. Vooral als de mannen ook nog eens overgewicht hadden of een hoge bloeddruk nam het risico nog verder toe, tot driemaal zoveel. De groep die het hoogste risico liep kreeg minder dan het equivalent van een half glas jus d`orange binnen, tegen de andere mannen die ongeveer twee glazen jus d`orange dronken, of een ander supplement met vitamine C. Vitamine C is een anti-oxidant, die vrije radicalen in het lichaam neutraliseert. Vrije radicalen beschadigen de verder gezonde cellen.
NEW YORK - People
who consume lower-than-average levels of vitamin C may have a higher risk than
others of developing stroke, according to European researchers. Dr. Sudhir Kurl and colleagues from the
University of Kuopio in Finland found that middle-aged men who had relatively
low levels of vitamin C in their blood had a twofold higher risk of stroke than
men with the highest blood levels of the vitamin. Furthermore, the risks
associated with low blood levels of vitamin C were higher in men who were overweight or had high blood pressure,
also known as hypertension.
"I would say that low vitamin C in the
presence of hypertension increases the risk of stroke," Kurl told Reuters
Health. Kurl and his team measured the levels of vitamin C in the blood of 2,419
men who were between 42 and 60 years old when the study began. The investigators
then followed the men for about 10 years, and noted how many had a stroke.
During the study period, 120 study participants suffered a stroke, the authors
report in the June issue of Stroke: Journal of the American Heart Association.
Men who had the lowest levels of vitamin C in their blood--less than half of
what was measured in men with the highest amount--were 2.4 times more likely
than those with the most vitamin C to experience stroke. In addition, men who
took in the smallest amounts of vitamin C and also had hypertension or were
overweight were almost three times as likely to experience stroke as those who
had a high vitamin C intake and did not suffer from either condition. Men with
the lowest amount of vitamin C in their blood consumed only the daily equivalent
of around one-half a glass of orange juice in their diets, whereas those with
the highest blood levels took in the equivalent of about two full glasses per
day. In an interview with Reuters Health, Kurl explained that there are many
methods by which vitamin C might reduce the risk of stroke. The vitamin acts as
an antioxidant, he said, which neutralizes the free radicals generated in the
body during metabolism. Free radicals can be highly damaging to other body cells,
and have been implicated in the aging process and atherosclerosis. Antioxidants
like vitamin C protect the body from free radical damage by helping to prevent
free radicals from forming, and by disarming already-generated free radicals,
Kurl noted. Furthermore, the vitamin can also help prevent atherosclerosis
"by strengthening the artery walls, by taking part in the synthesis of
collagen, and also by preventing the undesired adhesion of white blood cells at
the site of the damaged arteries," Kurl said. Kurl added that people with
more vitamin C in their blood likely ate a diet that was balanced and rich in
fruits and vegetables, and therefore might be more health-conscious overall than
their peers with lower vitamin intake. Therefore, other healthy aspects of their
lifestyles, besides vitamin C intake, could also have influenced stroke risk.
"It is possible that vitamin C alone was not responsible for the results
presented in the present study," Kurl and his colleagues note.
SOURCE: Stroke
2002;33. Juni 2002