Content of selected nutrients and heavy metals in prenatal multivitamins and minerals: an observational study

Increasing consumer reliance on prenatal multivitamins and minerals (PMVMs) underscores the importance of ensuring their quality and safety. Adequate choline and iodine intakes during pregnancy are crucial for fetal development, yet discrepancies between labeled and actual content in PMVM products pose significant health risks. Additionally, the potential presence of toxic heavy metals, such as arsenic, lead, and cadmium, raises concerns about potential adverse health effects.

This study aimed to evaluate nonprescription and prescription PMVMs regarding choline and iodine content as well as arsenic, lead, and cadmium.

This observational study evaluated a convenience sample of nonprescription and prescription PMVM products from online retailers and local retail pharmacies. Products were analyzed using liquid chromatograph mass spectrometry for choline and inductively coupled plasma mass spectrometry for iodine, arsenic, lead, and cadmium. Choline and iodine actual amounts were compared with reported label amounts and heavy metal amounts were compared with United States Pharmacopeia standards.

In total, 32 nonprescription and 15 prescription PMVM products were analyzed. Choline amounts were reported on 12 of the 47 (25.6%) products including 5 (41.7%) within 20% of the claimed amount, 2 (16.7%) over the claimed amount by >20%, and 5 (41.7%) under the claimed amount by >20%. Iodine amounts were reported on 25 of the 47 (53.2%) products including 4 (16.0%) within 20% of the claimed amount, 20 (80.0%) under the claimed amount by >20%, and 1 (4.0%) over the claimed amount by >20%. Measurable amounts of arsenic, lead, and cadmium were found in 7 (14.9%), 32 (68.1%) and 29 (61.7%) PMVMs, respectively; however, no PMVMs exceeded United States Pharmacopeia standard limits.

Current PMVM products are misleading through omission or inaccurate content of essential nutrients. Federal regulation of dietary supplements in the United States is needed to ensure accurate content of essential nutrients in PMVM formulations.