The study in rats, one of the first scientific inquiries into
soy milk and ADHD, indicates that the mineral manganese may
cause behavioral problems if consumed in high doses. The study
appears in the August issue of NeuroToxicology. Francis
Crinella, professor of pediatrics, and his colleagues at UCI and
UC Davis found that giving rats increasing levels of manganese
during infancy resulted in behavioral changes at higher doses.
The researchers also found that manganese exposure resulted in
lowered levels of the neurotransmitter dopamine, which plays a
key role in inhibiting behavior seen in cases of ADHD.
"Manganese is a mineral that's essential for life. But past
studies on manganese miners have shown that it causes a number
of behavioral problems," Crinella said. "Soy milk formula
contains about 80 times the levels of manganese found in breast
milk, posing the risk that infants could receive too much
manganese in the first weeks of life. While we've shown that
behavioral problems can result from manganese e