English: This flow chart shows how mercury exposure may impact child learning. The form of mercury is not relevant. Exposure may occur via inhalation or ingestion. Upon exposure to mercury (Hg), in a healthy child with adequate nutrition, the Metallothionein (MT) gene will produce MT metal carrier protein which will help eliminate the Hg from the body. If the child consumes an unhealthy diet of excessive ultra-processed food intake with exposures to high fructose corn syrup (HFCS), mineral imbalances may occur (e.g., zinc (Zn) loss and copper (Cu) gain) and there will not be enough Zn to build the MT protein to eliminate the Hg. As the Hg builds up in the child's bloodstream, there will be oxidative stress and this stress in the brain will reduce neuronal plasticity and impair the child's learning ability. Hg exposure from fish consumption is a special case. As long as the fish or diet contains enough selenium (Se) to support the glutathione system then the Hg in fish should not be a problem. Metallothionein and glutathione proteins are both needed to successfully detoxify and excrete Hg. Dufault et al. (2009). Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children. Behavioral and Brain Functions. 5:44.