Early exposure to natural elements that are toxic – cadmium, mercury, and lead – can have long-term adverse health consequences. Children exposed to these elements while still in the uterus and while breast-feeding may suffer lasting damage to the brain and nervous system and to the kidneys and liver. The question is: to what extent can selenium supplementation reduce the risk of toxic damage?
Given the dangerous nature of these poisonous heavy metals – cadmium, mercury, and lead – both for the mother and for the fetus and the neonate, it is difficult to carry out randomized controlled studies. Instead, the best evidence we have for the beneficial effects of selenium supplementation comes from studies that relate the degree of exposure and the selenium status of the mother and the child.