How susceptible children are to low-level lead toxicity -- an ailment particularly pervasive among children living in older homes in "high-risk" areas -- may be related to what they eat. Sheri Zidenberg-Cherr, a UC Davis Cooperative Extension nutritionist who studies the relationship between nutrition and children's physiological response to lead, says undernourished children may be affected more by lead than are those with adequate diets. Lead-based paint, lead-contaminated soil and some types of ceramic cookware that have not been properly fired, all contribute to increased lead levels in the blood. The effects in children can include hyperactivity, poor learning ability and lower IQ test results.