In a shocking revelation, researchers of a new study published in The American Journal of Clinical Nutrition found alarming levels of lead and arsenic in several prenatal vitamins, while many others missed vital nutrients such as choline and iodine, which has raised concerns about the safety of expecting mothers taking these supplements during pregnancy.
Around 47 prenatal vitamins including 32 over-the-counter and 15 prescription were tested by the researchers from the University of Colorado Anschutz Medical Campus for their choline and iodine levels as well as the levels of arsenic, lead and cadmium in them.
In what can pose a significant risk to pregnant women, as many as seven products had arsenic amounts above the purity limits set by the US Pharmacopeia, two had too much lead, and 13 had excess amounts of cadmium.
Risks of lead, cadmium and arsenic exposure during pregnancy
Lead, cadmium, and arsenic exposure during pregnancy can significantly harm both the mother and the developing baby. Lead can affect the nervous system, leading to developmental delays and learning disabilities in children. Cadmium can damage kidneys and bones, and long-term exposure increases the risk of preterm birth. Arsenic exposure is linked to an increased risk of miscarriage, low birth weight, and developmental issues. These toxins can also impair fetal growth.
“The presence of contaminants, especially cadmium, was … concerning,” said Laura Borgelt, the study’s first author.
The research team also found out that the products were missing in certain key nutrients and did not match what was listed on the labels.
The missing nutrients in many prenatal supplements
Around 450 milligrams per day of choline, an important nutrient for brain development, cognitive function, and preventing birth defects is recommended during pregnancy while 550 mg is needed during lactation.
The researchers discovered that only 12 of the 47 products, which comes to around 26%, listed choline, and only five products contained the amount of choline promised on the label.
Similarly, iodine is crucial for producing thyroid hormones which can ensure proper fetal growth and development. The recommended iodine intake is 220 micrograms per day for pregnant women and 290 mcg/day for lactating moms. However, only four out of the 25 products that listed iodine content, had the amount mentioned on the label.
Essential nutrients needed during pregnancy
During pregnancy, essential nutrients and their approximate daily recommended amounts include:
Folic Acid (Folate): 600 mcg – critical for preventing neural tube defects.
Iron: 27 mg – supports increased blood volume and oxygen delivery.
Calcium: 1,000 mg – for fetal bone and teeth development.
Vitamin D: 600 IU – aids in calcium absorption and immune health.
Protein: 70–100 g – supports fetal growth and maternal tissue repair.
Omega-3 Fatty Acids (DHA/EPA): 200–300 mg – important for brain and eye development.
Iodine: 220 mcg – essential for fetal brain development.
Vitamin C: 85 mg – enhances iron absorption and supports tissue repair.
Zinc: 11 mg – necessary for growth and immune function.
(Picture courtesy: Freepik)
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I’m Manas Ranjan Sahoo: Founder of “Webtirety Software”. I’m a Full-time Software Professional and an aspiring entrepreneur, dedicated to growing this platform as large as possible. I love to Write Blogs on Software, Mobile applications, Web Technology, eCommerce, SEO, and about My experience with Life.