High dose vitamin C linked to lower heart attack risk

People who supplement with high doses of vitamin C could be reducing their risk of major heart disease events like heart attack, suggests a new analysis of prospective studies.

Epidemiologic research has suggested that higher intakes of fruit, vegetables, and wholegrains can lower risk of coronary heart disease.

However it is not yet clear whether the antioxidant vitamins in these foods are responsible for this protection or if other factors are playing a role too, said the researchers.

The international team pooled data from nine prospective studies that included information on intakes of vitamin E, carotenoids, and vitamin C, with a 10-year follow-up to check for major incident coronary heart disease events in people who without the disease when the study began.

Dietary intake of antioxidant vitamins was only weakly related to a reduced coronary heart disease risk, they write in the December issue of the American Journal of Clinical Nutrition.

However subjects who took more than 700 mg of vitamin C daily in supplement form appeared to reduce their risk of heart disease events by 25 per cent compared to those who took no supplements.

Earlier this year, researchers at the University of California produced results showing that vitamin C appears to reduce levels of C-reactive protein, a marker of inflammation and possibly a better predictor of heart disease than cholesterol levels.

Supplemental vitamin E intake was not significantly related to reduced coronary heart disease risk, according to the authors.

Reference
Knekt P, Ritz J, Pereira MA, O'Reilly EJ, Augustsson K, Fraser GE, Goldbourt U, Heitmann BL, Hallmans G, Liu S, Pietinen P, Spiegelman D, Stevens J, Virtamo J, Willett WC, Rimm EB, Ascherio A. Antioxidant vitamins and coronary heart disease risk: a pooled analysis of 9 cohorts. Am J Clin Nutr. 2004 Dec;80(6):1508-20