Pregnancy, Calcium, and Levels of Lead
( NY Times )
For pregnant women, low calcium levels can let more lead find its way into their blood, according to a new study that also found that the problem increased with age.
As much as 95 percent of the body's lead is locked inside bone tissue. Writing in this month's issue of The American Journal of Epidemiology , researchers from the University of North Carolina say pregnancy and the early years of menopause are the times when bone tissue is most likely to "demineralize," releasing lead into the blood.
In their study they checked blood lead levels in 195 pregnant women and compared the results against information gathered from patient histories. The researchers found that women whose calcium intake was below normal had lead levels significantly higher than normal. High levels can impair mental development in the child.
The researchers also found that older women with low calcium levels released more lead from their bones because more had accumulated over the years, particularly during the era of leaded gasoline. While the lead levels of 18-year-old pregnant women with low calcium intakes were 25 percent above those of their healthier peers, the gap widened to 99 percent at age 43.
Commentary: (Dr. Kaczor) We are all exposed to some level of lead throughout our lives and once ingested, it largely has two fates: either we excrete it through urination or it gets stored in bone. The article above implies that lead is released into the blood when calcium is deficient. The explanation is fairly simple: when there is not enough calcium in the diet, the body withdraws some calcium from its largest storage site, our bones. Calcium and lead are very similar elements in size and charge. Unfortunately, they are so similar that the body cannot distinguish between them, so both get released into the bloodstream.
Clearly, pregnant women and women likely to conceive, should take precautions to lower exposure to all heavy metals (lead, mercury, cadmium and arsenic are the most common) as well as maintain adequate calcium levels. It is important to remember that fetal development may be damaged by heavy metals before a woman knows she is pregnant.
While this article looked at pregnant women, where the health risk to the fetus is a grave concern, we are all at some risk from heavy metal toxicity. Nutrient deficiency (as mentioned above), stress and genetic weaknesses that limit excretion of metals may all play a role in accumulating heavy metals. This accumulation is called "body burden," and it can be tested and treated if need be. I encourage anyone with allergies, fibromyalgia, chronic fatigue syndrome, an autoimmune disease, a family or personal history of cancer, osteoporosis, memory loss, inexplicable rashes and children with behavioral disorders to be tested.
If you would like further information about heavy metal testing-method, cost, etc.-please call our office and we will be happy to speak with you.