Heavy Metals In Your Baby’s Prenatal Vitamins?

5 Steps for Protection While Taking Supplements

By Dr. Berkson

When an expectant mother goes to the trouble to see a specialist, is recommended prenatal vitamins, then buys and takes them, these are all steps she’s taking to “take care.” She is hoping to protect her unborn next generation.

That’s what many of us are trying to accomplish by being more informed, and then taking prophylactic steps to be safer. But sometimes hidden issues can make our efforts not only backfire, but also put your unborn child or yourself at even worse risk.

A number of studies have been pointing a finger at various products that are contaminated with toxic substances that are dangerous for your precious family.


Prenatal vitamins and heavy metals

Several groups of researchers wanted to test the safety of prenatal products available over-the-counter and at pharmacies (but not from physician’s lines that have very strict quality control). These scientists were from the University of Alberta, Canada, a Scandinavia Division of A.L.S. Laboratory Group from Luleå University of Technology, and the Department of Obstetrics and Gynecology from the University of Alberta.

They tested 26 commonly used prenatal vitamin brands, “including one prescription brand,” for toxic element contamination.

All samples contained lead. The average amount of lead exceeded established standards for lead toxicity safety. One sample was way over the safety level of lead and downright toxic. Three samples had inorganic (most dangerous type) arsenic levels that were above acceptable limits. Toxic aluminum, nickel, titanium and thallium were detected in every single prenatal product.

Toxic metals are called “toxic” because they are potentially damaging. They can damage brain function, alter behavior, damage kidney filtering, increase risk of cancer and diabetes, and are even linked to increasing vulnerability to neurologic diseases.

Toxic metals are highly linked to fatigue. Energy comes from ATP production. It is critical for mitochondrial function, which you experience as “energy.” Toxic metals damage energy production. For example, arsenic slows down the production of ATP and makes mitochondrial sluggish and dysfunctional. Toxic metals are also pro-oxidative, which means they damage essential enzymes and other critical physiological processes all throughout your biological real estate. Toxic metals can also act as hormone-altering chemicals.

What if a pregnant mom takes prenatal products that contain toxic heavy metals? There can be silent adverse changes in her baby’s brain development and behavior as well as future risk of disease.

Cumulative intake of prenatal supplements over many months of pregnancy may constitute, say these researchers, a significant source of toxic element exposure to both mother and her unborn child.

Keep in mind, several samples exceeded known standards for gestational toxic element exposure, yet these women were following the orders of their health professionals to safeguard their pregnancy. Most often prenatal products are consumed daily during gestation and postnatally for up to 18–24 months, with both doctors and mother-to-be believing that these supplements help baby and mom.

What to do? Purchase only doctor grade products. These have monthly regular analysis for toxic contaminants and, if any are found, these batches of products are discarded. That is one of the great services of physician lines, such as Biotics (I am going to start lecturing for them I trust their product so much), Thorne, Moss Nutrition, Designs for Health, Metagenics (I used to formulate for them), etc.

These are not the first reports of contamination of products. Studies on over-the-counter probiotics have shown that products sold at reputable drugstores and large chains have either insufficient product compared to what is stated on the label or are contaminated with bacteria or toxic metals.

Supplements aren’t the only potential route of toxicities. Food and water are now known to possibly contains toxic hormone-altering chemicals. So can air. Certain clays, even those used for detox, may contain contaminated toxic metals.


Confounding factors: Vitamin D

Healthy Vitamin D levels have all kinds of benefits. If a pregnant mom has healthy levels of vitamin D, this is linked to preventing premature birth. Vitamin D is a pro-hormone that reduces inflammation and increases a healthy uptake of calcium for bones.

But excessive vitamin D, more than the mom’s body really needs, can increase the uptake of toxic heavy metals. We think of Vitamin D as boosting calcium use by the body. But Vitamin D not only increases the uptake, absorption, and assimilation of calcium; it does the same for your body’s use of many essential inorganic elements (such as calcium, magnesium, copper, zinc, iron, and selenium).

And, of all things, did YOU know this, Vitamin D also can increase the uptake of toxic elements (such as lead, arsenic, aluminum, cobalt, and strontium)!

Thus, you do not want too much vitamin D. Especially during pregnancy!

A healthy level of vitamin D during pregnancy needs to be individualized by a medical nutritionist, and studies show that beneficial levels reduce fetal mortality and pre-eclampsia. On the average, vitamin D supplementation should be lower than 2000 IU/day. However, taking vitamin D daily along with more calcium (which the safe levels are getting lower and lower so much so, calcium supplementation should probably be off your list) has been shown to increase the risk of fetal death.


Which products are safest?

Labdoor is a supplement testing and rating service. Each product they test is sent to an FDA-registered laboratory where scientists perform key purity and label accuracy assays.

Labdoor did an analysis of 34 best-selling magnesium products in the U.S.

They looked to see how much magnesium was in the product versus what the label stated, and if the product contained heavy metals (arsenic, cadmium, lead, mercury).

What Labdoor testing found:

  • Many products did not have the levels of magnesium the labels stated. Oy! Only 9.5% of the products had what their label stated; 97.5% had more than their label claimed for magnesium. Natural Zest Ultimate Magnesium recorded the worst underage, with only 38.1 mg of its claimed 400 mg of magnesium per serving. On the whole, products deviated from label claims by an average of 11.5%. Natural Vitality Natural Calm had much more, 691.2 mg of magnesium per serving.
  • Magnesium comes on carrier salts.
    • Often when a label reads 180 mg of magnesium glycinate, much of that is the carrier salt and perhaps only 20 or 40 mg of that is the elemental magnesium. Then, you often absorb less than that depending on your levels of vitamin D, digestive enzymes, what foods you consume the mineral with, and other factors.
    • Amino acid chelates like magnesium glycinate demonstrate higher bioavailability than inorganic compounds like magnesium oxide. The bioavailability of magnesium aspartate, magnesium citrate, magnesium lactate, and magnesium malate falls somewhere in between. Magnesium taurate is linked to boosting energy. Magnesium threonate is the best to cross the blood-brain barrier.
  • In a clinical trial of 16 subjects, magnesium chloride absorption was found to be slightly higher than that of magnesium aspartate and magnesium lactate. This is an excellent route for magnesium taken topically. I love Dr. Shealy’s magnesium lotion, which is magnesium chloride.
  • None of the tested products had lead, cadmium, or mercury. But a number had arsenic. Arsenic—a carcinogenic and type-2 diabetes-promoting heavy metal— was found in 25 of 34 products! Total arsenic can be separated into “organic” and “inorganic” arsenic parts.

Inorganic arsenic is the more dangerous form. California Proposition 65 sets a safe daily intake limit on the inorganic portion at 0.1 mcg. In the Labdoor report, 2 out of every 3 products measured total arsenic levels that exceeded the inorganic arsenic limit. Long-term exposure to arsenic can cause cancer, developmental defects, cardiovascular disease, diabetes, and neurotoxicity.

  • Six products contained titanium dioxide, a whitening agent classified as “Generally Recognized as Safe” by the U.S. Food & Drug Administration, despite being linked to cancer and neurological damage.

What should you do? Live in a Seinfeldian bubble?


Five steps to get the best supplements with the least toxic metals:

  • Purchase physician brand nutrients. These are regularly tested for toxic metals and for amounts of constituents reflecting label levels. You can call these “physician” companies and request quality control reports and they fax them pretty much right away. That’s the kind of companies you want to buy and swallow products from.
  • Take sufficient minerals.
    • First, do this through food. A colorful rainbow plant-based diet supplies many natural bioavailable minerals. When your tissues contain sufficient and healthy levels of essential minerals, this “resists” the uptake of toxic Having healthy mineral levels protects your body against accumulation of toxic metals.
    • Second, through supplementation. But be careful. You do not need much calcium. That whole deal of calcium builds bones has been disproven for a long time. Calcium levels over 500 mg a day can promote fractures. It’s the whole spectrum of minerals that protects bones. You need multiple minerals, but do not take excess calcium. And if you have kidney issues, you want to be careful of your mineral intake. That is why a highly-trained medical nutritional practitioner is such a helpful professional.
  • Test and maintain healthy vitamin D levels: Healthy mineral status in conjunction with healthy levels of vitamin D protects you against toxic metals. Minerals help your body remove toxic metals and rinse them out of your body.
    • There is a lot of debate about what is a healthy vitamin D level. Many lab ranges (based on normal people, not scientific ranges) suggest that levels of 20 nanograms/milliliter to 50 ng/mL are healthy while below 20 is insufficient. Many functional doctors say that 50 and 60 ranges are more ideal. Some experts’ claim over 100 is optimal. But there are several papers linking levels of 90 and above to increased risk of cancer.
    • To be conservative, since at this time nobody really knows the optimum level of Vitamin D, and there are diverse types (isomers of vitamin D) and levels for all are still being tested, while too much can increase your toxic metals, in the mid-50s to mid-60’s seems prudent.
  • Healthy levels of magnesium inside cells leads to lower retention and increased excretion of lead. Excess vitamin D supplementation, in the absence of mineral or magnesium sufficiency, may result in more uptake of toxic element absorption and more exposure to toxic metals and endocrine disruptors.
  • Get your vitamin D levels tested, especially during pregnancy, to make sure you do not have too much or too little. You often need to request that your doc test it, as Vitamin D levels are not regularly tested by all practitioners.



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