A report from the Clean Label Project (CLP) claims protein powders contain high levels of heavy metal contamination, particularly lead and cadmium.
In the report, CLP says it tested 160 products from 70 top-selling brands, finding 47 percent of the products exceeded California Proposition 65 (Prop 65) safety thresholds for toxic metals. The report states there were three times the lead amount and twice the cadmium amount.
CLP says it conducted more than 35,000 tests on contaminants including lead, cadmium, arsenic, mercury and bisphenols.
“This study serves as a wake-up call for consumers, manufacturers, retailers and regulators alike. With a lack of comprehensive federal regulations specifically addressing heavy metals in dietary supplements, it is critical that the industry independently takes proactive measures,” CLP said in the report. “Clean Label Project’s findings call for a new level of transparency and stricter safety standards to protect consumers from long-term exposure to these contaminants.”
The Council for Responsible Nutrition (CRN) and Natural Products Association (NPA) responded to the study, calling it inaccurate and misleading.
NPA said the “study” falsely claims there is a “significant pretense of contaminants in some products and that it could post a serious safety threat to consumers.” NPA said the group denied requests from the association to disclose the methodology and data used in the study. NPA also called out CNN, for its reporting and for failing to contact NPA.
“The Clean Label Project is full of it, and it’s a shame that no one at CNN did basic reporting by neither asking for the methodology for this sham of a study nor contacted the NPA for analysis and comment. Instead, CNN blindly reported what the Clean Label Project told them without verifying,” said Daniel Fabricant, PhD, president and CEO of NPA. “In 2020, they pulled the exact same stunt attacking collagen supplements, but this so-called study is nothing but hot air. When we asked them to disclose its funders and the full methodology of the collagen study, they did not respond and instead hid from the truth. Again, we are demanding that they disclose this so-called study’s methodology instead of peddling misinformation and profiting from referred products to online retailers listed on its website.”
Dr. Andrea Wong, senior vice president, scientific & regulatory affairs at CRN, also responded to the study, stating:
“The Council for Responsible Nutrition supports efforts to ensure the safety and quality of dietary supplements, including protein powders. However, as we have noted in the past, reports like those issued by the Clean Label Project often lack critical context and risk misleading consumers rather than empowering them.
First, it is important to emphasize that the detection of contaminants, as highlighted in this report, does not inherently equate to a health risk. Modern analytical techniques can detect even trace levels of naturally occurring elements, such as heavy metals, which are present in soil, air, and water. These trace levels are often well below established safety thresholds set by federal agencies like the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA).
California Proposition 65, frequently referenced in CLP’s findings, imposes limits that are uniquely stringent and not aligned with federal guidelines. For example, it imposes a 1,000-fold safety factor below the level at which no harmful effects have been observed, and it requires labeling of products over that amount, not a ban on them. While CLP’s intentions to protect consumers are commendable, the lack of harmonization with FDA or EPA standards can result in unnecessary consumer alarm. CRN has consistently advocated for science-based federal standards that balance consumer safety with practicality and consistency across all states. Federal agencies regulate the manufacturing of food and dietary supplements, including testing and monitoring protocols for heavy metals.
The report’s methodology also warrants scrutiny. CLP has not provided sufficient transparency regarding how products were selected, the criteria for contamination thresholds, or the interpretive framework for their findings. Without such clarity, consumers and industry stakeholders cannot fully evaluate the validity of the claims. CRN urges CLP to publish its findings in peer-reviewed journals and provide recommendations grounded in scientific evidence.
Finally, as we move toward ensuring safety and transparency, we must encourage a unified regulatory approach that upholds reasonable, evidence-based standards. Aligning state initiatives like Proposition 65 with federal guidelines would reduce confusion for consumers and manufacturers while maintaining public safety. CRN and its members remain committed to collaborating with stakeholders to promote rigorous, transparent, and uniform safety standards across the dietary supplement industry.”
To read the full report, visit https://cleanlabelproject.org/wp-content/uploads/CleanLabelProject_ProteinStudyWhitepaper_010625.pdf.
