Content of selected nutrients and potential contaminants in prenatal multivitamins and minerals: an observational study

Background: 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.

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

Methods: 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 chromatography 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 contaminant amounts were compared with United States Pharmacopeia (USP) standards.

Results: 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%. Amounts of arsenic, lead, and cadmium above USP purity limits were found in 7 (14.9%), 2 (4.3%) and 13 (27.7%) PMVMs, respectively.

Conclusions: Current PMVM labels are misleading with the potential to harm pregnant persons and fetuses through omission or inaccurate content of essential nutrients and inclusion of heavy metals. Regulation is needed, and the Food and Drug Administration needs sufficient authority and staffing to oversee these dietary supplements.