Watchdogs refute study alleging toxicity and sub-par quality in prenatal vitamins

The Council for Responsible Nutrition (CRN) and the US Pharmacopeia (USP) are expressing “grave concerns” over the accuracy of recent research claiming prenatal vitamins don’t contain enough of the nutrients needed for healthy pregnancy, with some even containing high levels of toxic metals.

The study, published in the American Journal of Clinical Nutrition, checked choline and iodine levels in nonprescription and prescription prenatal vitamins bought online and in local shops.

Researchers claim to have found a significant gap between prenatal vitamins’ labels and actual amounts, with most lacking choline and iodine content. Heavy metals, such as arsenic, lead and cadmium, were also found in some products — amounts higher than the limits set by the USP.

However, CRN says USP purity limits as a standard “does not exist for the finished products tested in the study.” It says the study is inaccurate and has a flawed methodology. 

In its statement, USP said it has “determined that the limits as well as the units were incorrectly applied and that the values presented in the first publication of the study were inaccurate.”

“USP has directly communicated with the author to clarify the correct limits and units.”

Calming consumers

CRN says it seeks to calm pregnant people who have been alarmed by widespread media coverage.

“It is particularly unfortunate that it has taken a month since the study was initially released in pre-publication form and a press release was issued by the author’s university to get acknowledgment that the inflammatory conclusion was in error,” comments CRN president and CEO Steve Mister. 

“During that time, numerous media have erroneously reported on the study’s conclusions in reliance on misinformation. And countless women have unnecessarily experienced anxiety over the safety of their vitamin regimens during their pregnancies.”

Also, CRN details that “the referenced limits pertain to ingredient testing and are measured in mcg/g, not per daily dose. Correct application of the appropriate USP standards (General Chapter 2232 for dietary supplements) shows that all tested products were well below established safety limits for heavy metals.”

“This is consistent with findings from a separate, recent Government Accountability Office report, which confirmed that trace amounts of heavy metals in prenatal supplements are not a health concern based on FDA metrics.”