Protein powder is a popular go-to for fueling workouts, building muscle, and supporting overall nutrition. But recent findings might make you think twice before scooping that powder into your next smoothie. A new report has revealed that many popular protein powders contain concerning levels of lead and cadmium, two toxic heavy metals that can pose serious health risks.

What the Study Found

The Clean Label Project, a nonprofit organization focused on consumer safety, tested 160 protein powder products from 70 top-selling brands.

Nearly half (47%) of the tested protein powders exceeded California's Proposition 65 safety limits for heavy metals. Surprisingly, organic protein powders weren't necessarily safer, containing on average three times more lead and twice the amount of cadmium compared to non-organic products. Plant-based options, often perceived as healthier, showed higher levels of contamination, with three times more lead than whey-based alternatives.

Even your flavor choice matters — chocolate-flavored powders contain up to four times more lead than vanilla-flavored options.

How Do Lead and Cadmium Get Into Protein Powder?

This begs the question of how these heavy metals even end up in protein powder. Lead and cadmium are naturally occurring elements found in soil and water. As plants grow, they can absorb these metals, which can then make their way into plant-based protein powders derived from ingredients like peas, rice, and hemp. However, even whey-based protein powders can be affected if the cows producing the milk are exposed to contaminated feed or water.

Why Is This Concerning?

While occasional exposure to trace amounts of heavy metals may not cause immediate harm, long-term consumption can lead to serious health effects. According to the World Health Organization (WHO), exposure to lead can affect multiple body systems and is particularly harmful to young children and women of childbearing age.

Lead can impair brain function, lower energy levels, and affect heart health, according to the United States Environmental Protection Agency (EPA). Prolonged exposure has been linked to high blood pressure, kidney damage, and reproductive issues. The EPA states that no level of lead is safe for human consumption.

The U.S. Department of Labor adds that cadmium may interfere with kidney function and bone health, and has been linked to an increased risk of certain cancers.

This is especially concerning considering the rise in popularity of protein supplementation in teens. According to a recent C.S. Mott Children’s Hospital National Poll, two in five parents report that their teen has consumed protein supplements in the past year. Lead can permanently affect children’s brain development, resulting in reduced IQ, behavioral changes including reduced attention span and increased antisocial behavior, and reduced educational achievement.

How to Identify Safer Protein Powders

The good news is that you can take steps to reduce your risk. Here’s how to choose a cleaner protein powder:

• Look for third-party testing – Brands that voluntarily test their products for heavy metals often provide certificates of analysis (COAs). Look for labels that mention testing by organizations like NSF Certified for Sport or the Clean Label Project.
• Choose organic, but verify testing – While organic protein powders may have fewer pesticide residues, they can still contain heavy metals from soil contamination. Always check for third-party test results.
• Go vanilla – If you're a chocolate lover, consider switching to vanilla-flavored powders, which typically contain less lead and cadmium.
• Check independent reports – Consumer advocacy groups periodically test protein powders for heavy metals. Reviewing these reports can help you make informed choices.

Other Ways to Get Your Protein Safely

If you’re concerned about potential contaminants in protein powders, consider incorporating more whole-food protein sources into your diet, which is the safest option. Mix up your protein intake with lean meats, fish, eggs, dairy, legumes, nuts, and seeds to provide high-quality protein without the risk of heavy metal exposure from processing.

The Bottom Line

While these findings are concerning, they don't mean you need to completely avoid protein powders. By making informed choices and being mindful of your consumption, you can continue to support your fitness goals while prioritizing your long-term health.

By being a smart consumer — checking for third-party testing, reviewing ingredient sources, and opting for whole-food protein when possible — you can protect your health while still meeting your nutritional needs.