Many protein powders on the market may contain dangerous amounts of heavy metals such as lead and cadmium.

Clean Label Project, a consumer product safety nonprofit, tested 160 products from 70 top-selling supplement brands. Nearly half of the protein powders tested had unsafe levels of heavy metals. The report also found that plant-based protein powders had three times the amount of lead as whey-based products, and chocolate-flavored powders had four times more lead than vanilla versions.

This isn’t the first time protein powders have been found to contain heavy metals. A 2018 Clean Label Project report found measurable levels of lead in 75% of the tested protein powders.

However, experts say you don’t need to throw out your protein powder just yet.

“While it’s wise to be mindful, the good news is that small, incremental changes—like choosing brands that prioritize rigorous testing for heavy metals—can make a big difference. Awareness doesn’t mean avoiding certain foods altogether; it means being intentional about the ones you pick,” Jaclyn Bowen, MPH, MS, executive director of Clean Label Project, told Verywell in an email.

How Do Heavy Metals Get Into Protein Powders?

Heavy metals like lead, cadmium, and arsenic occur naturally in the earth’s crust and can enter the soil through volcanic eruptions and erosion. Plants absorb heavy metals from the soil, and humans and animals can be exposed to them by consuming these plants.

This may explain why the report found that chocolate-flavored protein powders contain four times more lead than vanilla-flavored powders. “Because chocolate comes from a plant and vanilla can be synthetic, it does make more sense that the chocolate products would have more heavy metals than the vanilla products,” Kelly Krisna Johnson-Arbor, MD, a medical toxicologist at MedStar Georgetown University Hospital, told Verywell.

Toxic heavy metals have been detected in other foods and consumer products like baby food, Florida-grown lettuce, and wine. Last year, lead and arsenic were found in tampons, possibly due to cotton absorbing metals during the growing process.

However, growing condition isn’t the only source of heavy metals in these items. Manufacturing processes—either intentionally or unintentionally—can also introduce heavy metals into certain products, Johnson-Arbor added.

Should You Stop Using Protein Powders?

It’s concerning to hear that popular protein powders contain heavy metals, but you don’t necessarily need to stop using these supplements. A 2020 study found that heavy metal exposure from protein powders doesn’t increase the risk of negative health outcomes.

“For most adults, the negative effects from exposure to cadmium and lead result from repeated, long-term exposures,” Tunde Akinleye, an analytical chemist and test program leader of food safety and nutrition testing at Consumer Reports, told Verywell in an email.

However, the high lead levels detected in the study “would be a good reason to reduce the frequency of consumption of protein supplement or look for different, safer sources of protein,” Akinleye added.

Pregnant people and children may especially want to consider other protein sources because lead and other heavy metals can lead to pregnancy loss or harm a developing brain.

Check for Certification on Protein Powder Labels

The Food and Drug Administration (FDA) has a Toxic Elements Working Group that is trying to find ways to reduce exposure to these heavy metals in food, cosmetics, and supplements, but protein powders and other dietary supplements are not tested for safety by the agency before hitting store shelves.

When you purchase a protein powder or a vitamin product, you don’t necessarily know what’s in it, Johnson-Arbor said. But you can look for certification from USP, ConsumerLab, and NSF.

“It’s not perfect,” she added. “But it’s probably the best way of ensuring that your supplements have been tested and have been found to be free of contamination.”