Consumer Reports: Popular Prenatal Vitamins Show Variations in Potency

Consumer Reports recently conducted a round of testing on 17 over-the-counter prenatal vitamins for label accuracy and contaminants, analyzing products for heavy metals and for potency of specific nutrients.

While only trace amounts of heavy metals were found in only three of the tested products, nearly all (15 of 17) products had overages or shortages of key nutrients, including folate or folic acid.

Gummies, in particular, had significant shortages, with four of eight tested gummies containing folate levels well below the amounts listed on the Supplement Facts panel.

“Only two products, Carlyle for Her Prenatal Multi-Vitamin & Mineral Formula and Bird&Be Complete Prenatal Pack, contained nutrient levels that aligned with the labeled amounts in our testing,” wrote Jessica D’Argenio Waller, nutritionist and baby and health writer at CR. “Prenatal vitamins can play a critical supporting role in maternal and fetal health. All of the products we tested are safe to consume … our findings underscore the lack of oversight and label standardization around prenatal supplements specifically – and dietary supplements in general.”

D’Argenio Waller reported that CR analyzed capsules, tablets, softgel, and gummy formats, analyzing nine vitamins and minerals from each, compared against both Supplement Facts panels and USP thresholds. USP tolerance thresholds specify allowable ranges in a multivitamin relative to the amount stated on the label; the minimum is typically 90% and the upper limit differs based on the nutrient and supplement format. USP verification, among other things, confirms adherence to this threshold.

Secret shoppers from CR purchased one to three lots of each prenatal and sent them to an outside laboratory for testing.

Each product was tested for calcium, iron, zinc, vitamins A, C, D, and E, folate, and riboflavin. Most products evaluated didn’t contain DHA. Testing confirmed whether nutrients exceeded USP tolerable upper intake level, or USP minimums.

Capsules

Carlyle For Her Prenatal Multi-Vitamin & Mineral Formula and Bird&Be Complete Prenatal Pack each passed with flying colors. However:

• Up&Up Prenatal Daily Vitamins had vitamin A levels below USP tolerance;
• Spring Valley Prenatal Mini Multivitamin/Mineral had vitamins C and E below threshold;
• Needed Prenatal had vitamins C and B9 below threshold;
• Seeking Health Optimal Prenatal had vitamins A and B2 below threshold and vitamin D above USP upper limit;
• Pink Stork Total Prenatal + DHA had vitamins A, D, and B2 below threshold;
• Perelel 1st Trimester Prenatal Pack (Core Prenatal Only) had vitamins A, C, E, and B2 below threshold;
• Thorne’s Basic Prenatal’s vitamin B2 level was below threshold, while vitamin B9 and iron exceeded USP’s upper limit.

Gummies

Vitafusion Prenatal gummies; Nature Made Prenatal Folic Acid + DHA + Choline gummies; and Olly Essential Prenatal Folic Acid + DHA gummies each met label claims within USP threshold. However:

• SmartyPants Prenatal Organic Multi & Omegas had levels of vitamin D below threshold;
• CVS Health Prenatal Gummies had vitamin B9 levels below threshold;
• One A Day Prenatal Multi Gummy had vitamin B9 below threshold;
• Amazon Basics Prenatal & DHA gummies ahd vitamin B9 below threshold;
• Centrum PreNatal Multivitamin Gummy had vitamin B9 below threshold.

Of all 124 nutrients analyzed across 17 products, 38 (31%) were outside the acceptable threshold, D’Argenio Waller reported, and while, in many cases, overages don’t have safety implications, there may be some health implications specific to fat-soluble nutrients when a consumer consistently takes a product that consistently exceeds labeled amounts.

Several brands that were tested responded to Consumer Reports’ analysis, noting that their products are formulated with overages to guarantee 100% of the label claim for the entire shelf life of the product, while overages are reviewed to ensure that they do not reach upper limit levels.

• Piping Rock, which manufactures Vitafusion and Carlyle, stated that they undertake rigorous testing to prevent excessive overages, and include a disclaimer on Vitafusion Prenatal Gummies that advises consumers about intentional overages.
• Thorne noted that certain nutrients may be formulated with “scientifically justified overages,” and that its product is third-party verified by NSF International.
• Pink Stork responded, noting that its own third-party lab testing found that nutrients met 100% of label claims, and that variation may “reflect differences in analytical methodology or other testing conditions.”
• Walmart told CR that it is committed to “safe, high-quality products and work continuously with our [sic] suppliers to review and ensure standards are met.”
• SmartyPants noted that acerola cherry extract is the source of its vitamin C, which can cause variation. “We formulate with carefully controlled overages where scientifically justified to ensure products continue to meet labeled potency throughout their shelf life, as required under FDA regulations,” the company told CR.
• CVS Health responded, noting that while it doesn’t manufacture its store brand products, it regularly tests its supplements with independent third parties.
• Amazon reported that Consumer Reports’ testing methodology is not appropriately calibrated for gummy vitamin formulations and is inaccurate.
• One A Day also noted that it intentionally includes overages in its products consistent with industry standards, “within levels considered acceptable from a health and safety perspective.”
• Perelel responded, noting that a re-test of its products confirmed CR’s findings, and has since made formulation adjustments to vitamin B2 levels. Other nutrients, which were within the USP range, may have varied due to differences in testing factors.
• Needed reported that its test results also differed from CR, and “we believe differences in analytical methodology may be a factor.”

Industry Responds

The Council for Responsible Nutrition (CRN) reported that CR’s findings require context. CR selected USP tolerance ranges as its benchmark, but those ranges are voluntary for products that do not claim to be USP verified, and falling outside them doesn’t violate FDA requirements.

“Several manufacturers reported different results from their own or independent laboratory testing. Analytical methodology, nutrient forms, product matrices, and calculation methods can all affect results,” CRN stated. “Certain nutrient forms and complex product matrices may require fit-for-purpose, scientifically valid analytical methods, and results can differ when a method has not been designed for the specific analyte and matrix being tested.”

Bird&Be reported that its products are developed by fertility doctors and OB-GYNs, and are Clean Label Project Certified to meet Prop 65 standards for heavy metals, and that CR’s findings back up years of the brand’s third-party testing. “Expecting parents deserve products they can trust,” said Samantha Diamond, CEO. “Bird&Be is committed to making supplements that are safe and effective, and its consistent recognition of Bird&Be confirms the commitment to high quality that we’ve made to our customers and healthcare providers since day one.”

Bayer conducted extensive testing internally and through a third-party laboratory in response to CR’s testing, and stands behind the label claims made for nutrient potencies. “Improper sample preparation methods can produce inaccurate folic acid results. This may explain the discrepancy between the two tests. Bayer repeated this testing on five different samples of One A Day Prenatal Gummies from the same lot under each condition and determined that sample preparation was critical to accurate results. The difference in results may have been caused by how the product was prepared for testing, not by the actual amount of folic acid in the product … the low reading reflected how the product was tested, not the amount of folic acid in the gummies.”