Vitamin C may reduce blood lead levels
Source:	The Journal of the American Medical Association 1999; 281:2289-2293, 2294-2298
Date:	June 22, 1999
NEW YORK, Jun 22 (Reuters Health) -- High intake of vitamin C may help to reduce blood lead levels in individuals exposed to the toxin, researchers report. Experts estimate that millions of American children have high levels of lead in their blood, which can affect their neurological development. These findings ``may have public health implications for control of lead toxicity,'' suggest Drs. Joel A. Simon and Esther S. Hudes of the University of California, San Francisco. Their findings are published in the June 23/30 issue of The Journal of the American Medical Association. Lead has been banned in US paint, gasoline, and other sources since the 1970s. However, children across the country may still be exposed to lead through paint chips and dust found in homes built prior to that time. Lead accumulates in the body and is associated with behavior problems, language deficits, and mental retardation. In their study, the California authors examined data from a large national survey of more than 19,000 individuals 6 years of age and older. They report that high blood levels of vitamin C are associated with lower blood lead levels in youths and adults. In fact, children ranked in the top third in terms of blood levels of vitamin C had an 89% lower incidence of high blood lead levels, compared with children ranked in the bottom third of intake. Among adults, high blood vitamin C appeared to reduce incidence of lead contamination by up to 68%. The authors stress they "cannot be certain" of the exact relationship between blood levels of lead and vitamin C, and it remains unclear whether high vitamin C intake causes a decline in levels of lead in the blood. Still, previous studies have suggested that vitamin C may be a strong 'leaching agent' for lead, helping to eliminate the toxin from the body. Simon and Hudes believe future research should focus on possible mechanisms by which vitamin C might help rid the body of lead. Should such a mechanism be found, dietary recommendations urging ``higher intakes of ascorbic acid may have public health implications for the prevention of lead toxicity,'' according to the investigators. In a statement issued by the University of California, San Francisco, Simon recommended boosting vitamin C intake by increasing the amount of fresh fruits and vegetables in the daily diet. Alternatively, a multivitamin or small dose of vitamin C may be taken ``as an insurance policy.'' "Humans are one of the very few mammals that do not produce vitamin C on their own," he said, "so all of it must be obtained from dietary sources."