I ran across an interesting research article today in the EPA’s Environmental Health Perspectives that indicates calcium supplementation may decrease the amount of lead found in breast milk. The rationale is that in order to provide adequate calcium to a developing fetus or breast feeding child, the mother’s body will draw calcium from the bones. Because lead is sequestered in the bones as well, the release of calcium from bones also frees the stored lead. This causes higher blood lead levels and higher breast milk lead levels.
From a physiology perspective this makes sense and so does supplementing with some calcium in pregnant or breast feeding mothers – especially if they have a history of lead exposure or toxicity.