Scientists are not sure why lead apparently causes tooth decay, but one theory is that "it may alter saliva, the best mouth cleanser and cavity fighter there is," says Horowitz. Scientists are also not sure about the full implications of another lead study reported in the same AMA journal. This second study found that people with more vitamin C in their blood had lower levels of lead. Scientists are not ready to certify vitamin C as a lead antidote -- more study is needed -- but kids should be eating vitamin C-packed foods anyhow, says Horowitz. "Parents worried about their children’s exposure to lead now have one more reason to encourage them to eat foods like citrus fruits," she adds.
To the many detrimental consequences of lead poisoning (one of the most serious of which is brain damage), add one more: tooth decay. A new study published in Wednesday’s Journal of the American Medical Association indicates that children with higher levels of lead in their blood risk having more problems with tooth decay. About a million youngsters in the U.S. have high lead levels in their blood, and the study suggests that the poison could be responsible for as many as 11 percent of cavities in children nationwide. "The study illuminates the fact that lead is a systematic problem," says TIME health reporter Janice Horowitz. "Once ingested, it goes to many parts of the body."