Friday Favorites: Lead in Calcium Supplements

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I’ve explored the role calcium supplements may play in reducing lead exposure during pregnancy and breastfeeding, but this is assuming that the supplements aren’t themselves contaminated. It all started with an extraordinary case report published in 1977, entitled “Lead-Contaminated Health Food.”

“A doctor prescribed a dietary supplement…for a young woman with [painful periods].” Not just any woman, though: TV and film actress Allison Hayes, famous for such roles as Attack of the 50-Foot Woman. And, not just any physician, but physician to the stars Dr. Henry Bieler, who told his patients to forget about toxic drugs. “Food is your best medicine”—which, in this case, was a calcium supplement made from horse bone. She took it every day, but got weaker and sicker, and by 1967, her acting career was over, when she was unable to walk without a cane. She saw doctor after doctor after doctor, to no avail. She decided she could give up, commit suicide, or figure it out herself.

So, she had some friends drive her to a medical library. By then, she couldn’t even walk, and “had to be carried in.” She sat on the floor day after day, and finally came across a book on industrial toxicology that described what she soon realized was a classic case of lead poisoning. She paid to have the calcium supplement tested, and indeed, it was full of lead. At first, she was relieved, but “[t]hen the anger set in.” Doctor after doctor had basically dismissed her as hysterical, and she had to depend on herself to end up educating them.

The silver lining was that the FDA, in a letter, actually credited her for being “a ‘key stimulus'” for their plans to look into regulating heavy metals in foods and supplements. Unfortunately, the letter arrived after she had already died, from leukemia, which may have been triggered by the lead poisoning, or the 300 X-ray exams she got from those 22 baffled physicians.

You’d think the supplement industry would clean up its own act, but perhaps “[i[t is unrealistic to expect the ‘health food’…and ‘wellness’ [industry] to dampen their evangelistic promotion of these products” on their own. Where did the lead come from? Well, lead gets stored in your bones; and so, when you eat supplements made out of bones, you can get exposed. So, was that one calcium supplement just “the tip of an iceberg”? At first, we thought it was just from the bone supplements and dolomite, a mineral that can be lead-contaminated. But then, calcium carbonate—oyster shell calcium, chelated calcium─was found to have comparable lead levels to animal bone. And so, this inspired a comprehensive survey of the “Lead content [of] 70 [different] brands of calcium supplements.” And, “lead levels…varied by almost 300-fold,” some of which were two, three, or even four times the tolerable daily intake of lead for children—especially the most common: “natural source calcium,” like oyster shell, with more than half exceeding the benchmark for children.

A follow-up study confirmed that most calcium supplements from natural sources exceeded at least some of the most stringent lead standards, but the levels only got up to about eight micrograms, whereas some of the synthetic sources were up to three times that.

A small human study of calcium citrate was performed, in which bone biopsies were taken before and after about five years of supplementation. No change in the control group, as expected, and only a statistically insignificant increase in the calcium citrate group, though “[O]ne [can’t] assume that a given brand is uniformly safe, because some of their products may have high and others low lead levels.” So, name brands, or “recognized pharmaceutical companies” that should know better, are no guarantee.

But, the good news is that after decades of concern, lead levels in calcium supplements have come down—so much so that lead level changes in your blood, taking the average lead-contaminated calcium supplement, would be “minimal” at this point. So, these findings on supplement lead contamination should be a cause for “celebration,” not “alarm”—or at least according to a calcium supplement manufacturer consultant.

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Motion graphics by Avocado Video