Heavy Metals in Protein Powder: What 2025 Testing Found, How Risky It Is, and How to Choose Safer Products

A widely shared headline once claimed that only three protein powder brands were free of heavy metals and that many popular “healthy” companies had failed testing. The story was based on testing by an advocacy group, and similar findings have resurfaced repeatedly since. In October 2025, Consumer Reports published its own tests of protein powders and shakes and reported that more than two-thirds contained more lead than its experts consider safe for daily use.

Should people who use protein powder be worried? This article explains what the latest testing found, why heavy metals end up in protein supplements, how different measures of risk compare, what regulations apply, and how to choose and use protein powders more safely.

What the 2025 Testing Found

Consumer Reports tested 23 popular protein powders and ready-to-drink shakes for lead and other heavy metals. As Food Processing reported, more than two-thirds of the products contained more lead per serving than CR’s level of concern, which is 0.5 micrograms per day, and some exceeded it by more than tenfold. CR’s researchers said results were worse than in its previous testing about 15 years earlier, with higher average lead levels and fewer products with undetectable lead.

Plant-based products had the highest levels. On average, they contained about nine times as much lead as products made with dairy proteins such as whey, and twice as much as beef-based products. Two plant-based products contained between 12 and 16 times CR’s level of concern, and CR advised against using them at all. Dairy-based products generally had the lowest levels, though CR still advised against daily use for half of them. CR issued recommendations for how many servings per week of each product it considered reasonable.

NPR’s coverage emphasized context: modern testing can detect very small amounts of naturally occurring metals, detection alone does not equal a health hazard, and some manufacturers disputed CR’s approach, noting that their products meet the limits used by testing organizations. One manufacturer argued that on a per-gram basis its lead content was consistent with other plant-based protein foods. CR acknowledged that there are no federal limits on heavy metals in supplements and encouraged consumers to use its guidance when choosing products.

Why Protein Powders Contain Heavy Metals

Lead, cadmium, arsenic, and mercury occur naturally in soil and water, and human activities such as mining, industry, and past use of leaded gasoline and lead-based pesticides have added to the amounts in some areas. Plants absorb metals from soil and water as they grow, and some crops absorb more than others. When manufacturers concentrate protein from plants such as peas, rice, or hemp, they can concentrate some of the metals as well. Processing equipment and other ingredients can also contribute. Chocolate-flavored products may contain additional cadmium and lead from cocoa, which is known to accumulate these metals.

Animal-based proteins such as whey and casein, derived from milk, tend to contain less lead because animals filter and excrete some metals and milk is not a major route of accumulation. This explains much of the difference between plant-based and dairy-based products in testing.

How Much Lead Is Too Much?

There is no known safe level of lead exposure, particularly for children, whose developing brains are especially vulnerable. In adults, long-term lead exposure is associated with higher blood pressure, kidney damage, and cognitive effects. Because lead accumulates in the body over time, regulators and health groups aim to keep daily intake as low as possible from all sources combined.

Different benchmarks produce different conclusions. Consumer Reports’ 0.5 microgram per day level of concern is based on California’s Proposition 65 threshold for reproductive harm, a deliberately protective standard. The FDA has set interim reference levels for dietary lead of 2.2 micrograms per day for children and 8.8 micrograms per day for women of childbearing age, used to evaluate total dietary exposure from all foods. Against the stricter benchmark, many products exceed it; against the FDA reference levels, most single servings fall below them, though they add to lead from other foods.

A Different Risk Assessment

Not all analyses reach alarming conclusions. A 2020 human health risk assessment in Toxicology Reports by Sherilyn Bandara and colleagues used previously reported heavy metal concentrations from testing of 133 protein powder products and estimated exposure for typical consumers. The authors concluded that, at the reported concentrations, consumption was unlikely to pose non-cancer health risks, with hazard index values below 1. The authors work for a consulting firm, and their analysis relied on exposure assumptions that differ from those used by advocacy testing. Comparing these perspectives shows how conclusions depend on the benchmarks and assumptions used: a strict precautionary threshold flags many products, while a risk-based assessment of typical use finds lower risk.

Both perspectives agree on a practical point: lower is better, and people who consume protein supplements daily, especially at multiple servings, should pay attention to product quality.

What Regulations Apply

In the United States, dietary supplements, including protein powders, do not require FDA approval before sale, and there are no federal limits specifically for heavy metals in supplements. Manufacturers must follow current good manufacturing practices and are responsible for ensuring their products are safe and not adulterated. California’s Proposition 65 requires warnings on products sold in the state that expose consumers to chemicals above certain levels, including lead, which is why some protein powders carry warning labels. The FDA’s Closer to Zero initiative has focused on reducing heavy metals in foods for babies and young children rather than supplements.

Third-party certification programs fill some of the gap. Programs such as NSF Certified for Sport and Informed Choice test for banned substances and contaminants, and some, like the Clean Label Project, focus on heavy metals and other contaminants. Certification criteria differ, so it helps to understand what each seal covers.

Types of Protein Powder

Whey concentrate and isolate. Derived from milk during cheese making; whey isolate is more refined, with less lactose and fat. Whey digests quickly and is rich in leucine, an amino acid important for muscle building.

Casein. Another milk protein that digests slowly, sometimes used before sleep.

Egg white protein. A dairy-free animal protein option.

Beef and collagen proteins. Beef protein isolates and collagen peptides are animal-based; collagen lacks some essential amino acids and is not a complete protein on its own.

Soy protein. A complete plant protein with a long research history.

Pea, rice, hemp, and blends. Popular plant-based options, often blended to improve amino acid profiles. These tended to have the highest heavy metal levels in recent testing.

Each type has trade-offs in digestibility, taste, cost, allergens, and contaminant levels. People with dairy allergies or who avoid animal products may still choose plant proteins, ideally from brands with transparent contaminant testing.

How Much Protein Do People Need?

The recommended dietary allowance for protein for healthy adults is 0.8 grams per kilogram of body weight per day, a level designed to meet the needs of most people. Athletes, older adults, and people recovering from illness or surgery may benefit from more, and sports nutrition organizations have suggested higher ranges for people engaged in intense training. For most people, these amounts can be reached through regular meals. A single serving of protein powder typically provides 20 to 30 grams of protein, similar to a serving of chicken, fish, or Greek yogurt plus a glass of milk.

How Heavy Metal Testing Works

Laboratories typically measure heavy metals using inductively coupled plasma mass spectrometry, which can detect extremely small amounts, often parts per billion. Results can be expressed per gram of powder or per serving, and the distinction matters: products with large serving sizes, such as mass gainers, may deliver more metal per serving even if the concentration per gram is similar. Some testing organizations also consider recommended servings per day. Because lead levels can vary between production batches, a single test may not represent every container. Brands that test each batch and publish certificates of analysis offer more assurance than one-time results.

Reading a Certificate of Analysis

Some brands publish certificates of analysis (COAs) showing laboratory results for specific batches. A useful COA lists the lot number, testing laboratory, test methods, and measured levels of lead, cadmium, arsenic, and mercury, along with the units used. Check whether results are reported per gram or per serving, whether the lab is independent and accredited, and whether the lot number matches your container. A COA that shows only “pass” without numbers provides limited information.

How to Choose and Use Protein Powder More Safely

Step	Why it helps
Ask whether you need it	Most people can meet protein needs from food; supplements add convenience, not necessity.
Prefer dairy-based protein if tolerated	Whey and casein products tested lower in lead on average.
Look for third-party testing	Certifications and published certificates of analysis show contaminant testing.
Limit servings	Using one serving a few times a week rather than multiple daily servings reduces exposure.
Rotate products	Avoids repeated exposure to any single product’s contaminant profile.
Be cautious with chocolate flavors and mass gainers	Cocoa adds metals; large-serving products deliver more powder per serving.
Check for Prop 65 warnings	Indicates exposure above California’s strict thresholds.

Getting Protein From Food

For most people, food provides enough protein without supplements. Eggs, dairy products, fish, poultry, meat, beans, lentils, tofu, tempeh, nuts, and seeds are all good sources. Plant foods contain trace metals too, but eating a varied diet spreads exposure across many sources and provides fiber and nutrients that powders lack. Protein supplements can be useful for athletes with high needs, older adults struggling to eat enough, or people with specific medical conditions, ideally with guidance from a dietitian.

Who Should Be Most Careful

Pregnant and breastfeeding people, because lead can affect fetal and infant brain development.

Children and teenagers, who are more vulnerable to lead and rarely need protein supplements.

Heavy users, such as people using multiple servings daily or meal-replacement products as their main food source.

People with kidney disease, who may need to limit protein and should consult their clinician before using supplements.

Myths About Protein Powder and Heavy Metals

“Organic protein powder is free of heavy metals.” Organic certification addresses farming practices, not metals that occur naturally in soil.

“Plant-based always means cleaner.” Recent testing found plant-based powders averaged higher lead levels than dairy-based ones.

“If it were unsafe, it wouldn’t be sold.” Supplements do not require pre-market approval, and there are no federal heavy metal limits for them.

“One serving can poison you.” The concern is cumulative exposure over time, not acute poisoning from occasional use.

“More protein is always better.” Beyond your needs, extra protein offers little benefit and may add contaminants and cost.

Key Terms

Heavy metals: Elements such as lead, cadmium, arsenic, and mercury that can be toxic at certain exposures.

Level of concern: A threshold set by a testing organization or regulator above which exposure is considered undesirable.

Proposition 65: A California law requiring warnings for products exposing consumers to listed chemicals above set levels.

Certificate of analysis: A laboratory report documenting test results for a specific production batch.

Third-party certification: Independent verification that a product meets specific quality or safety standards.

The Bottom Line

Most protein powders contain some heavy metals, and recent Consumer Reports testing found that many, especially plant-based products, exceed a strict daily lead benchmark. Other risk assessments suggest typical use poses low risk, illustrating how conclusions depend on the standards applied. Because there are no federal limits, consumers who use protein supplements regularly should favor third-party tested products, consider dairy-based proteins when suitable, limit and rotate servings, and remember that whole foods can meet most people’s protein needs.

What Responsible Manufacturers Do

Manufacturers can reduce heavy metals in protein powders through ingredient sourcing, choosing suppliers whose crops are grown in lower-contamination soils, testing raw materials before use, testing each finished batch, and setting internal limits below regulatory or certification thresholds. Some companies publish their test results or participate in certification programs focused on contaminants. Formulation choices also matter: reducing cocoa content, avoiding high-metal botanical additives, and offering smaller serving sizes can lower metal content per serving. Consumers can reward these practices by choosing brands that are transparent about testing.

Comparing Protein Sources by Cost and Contaminants

Whole-food protein sources generally offer better value and nutrition than powders, along with fiber, vitamins, and minerals. Eggs, canned beans, lentils, milk, yogurt, canned fish, and chicken provide protein at modest cost. Protein powders are convenient, especially for people with busy schedules or high needs, but they are concentrated products whose contaminant levels depend on sourcing and processing. Using them as a supplement to a varied diet, rather than as a main protein source, limits exposure while keeping the convenience.

Special Note on Meal Replacements

Some powders sold as complete meal replacements are designed to be consumed several times a day, which can multiply exposure to any contaminants they contain. Two of the products with the highest lead levels in the 2025 testing were large-serving or meal-type products. People who rely on meal replacement powders for a large share of their nutrition should pay particular attention to contaminant testing and discuss their diet with a clinician or dietitian.

Children, Teens, and Protein Supplements

Protein powders are increasingly marketed to teenagers involved in sports and fitness, and some parents give them to children who are picky eaters. Pediatric experts generally advise that children and teens can meet their protein needs through food, and that supplements are rarely necessary unless recommended by a clinician for a specific medical reason. Because children are more vulnerable to lead and other heavy metals, and because supplements may contain other ingredients not suitable for young people, families should be especially cautious. A registered dietitian can help young athletes plan meals that support training without relying on powders.

Pregnancy and Breastfeeding

Lead can cross the placenta and can be stored in bones for years, released during pregnancy and breastfeeding. Health authorities emphasize minimizing lead exposure during pregnancy. People who are pregnant or breastfeeding and use protein supplements should discuss them with their clinician, choose third-party tested products with published low heavy metal levels, and prioritize whole-food protein sources. Prenatal care providers can also check for other sources of lead exposure, such as older housing or certain imported products.

What the Research Still Doesn’t Know

Important questions remain. Few studies measure blood lead or other biomarkers in people who regularly use protein supplements, so actual contributions to body burden are uncertain. Testing by different organizations uses different methods, benchmarks, and product samples, making comparisons difficult. Batch-to-batch variation means one test may not represent a brand over time. Research on cumulative exposure from multiple sources, including food, water, and supplements, would help put protein powder risks into context. Until then, a precautionary approach that limits unnecessary exposure is reasonable.

Questions to Ask a Protein Powder Brand

Do you test every batch for lead, cadmium, arsenic, and mercury? Which laboratory performs the testing, and is it accredited? Can I see the certificate of analysis for my lot number? What limits do you use, and how do they compare with Proposition 65 or other benchmarks? Where do your protein ingredients come from? Have you changed suppliers recently? Brands committed to quality should be able to answer these questions clearly, and reluctance to share information may itself be informative.

Balancing Convenience and Caution

Protein powders can be genuinely useful: they help athletes recover, older adults maintain muscle, and busy people meet protein targets. The goal is not to frighten people away from them but to encourage informed use. Choosing products with transparent testing, matching serving frequency to actual needs, and getting most nutrition from whole foods allows people to enjoy the convenience of protein supplements while keeping heavy metal exposure as low as practical.

Key Facts at a Glance

Consumer Reports’ October 2025 testing of 23 protein powders and shakes found that more than two-thirds exceeded its daily lead level of concern of 0.5 micrograms, a benchmark based on California’s Proposition 65. Plant-based products averaged about nine times more lead than dairy-based ones and twice as much as beef-based ones; all plant-based products tested used pea protein. The highest products contained 7.7 and 6.3 micrograms of lead per serving. A 2020 risk assessment based on earlier testing of 133 products concluded that typical consumption was unlikely to pose non-cancer risks. There are no federal heavy metal limits for supplements, so third-party testing and published certificates of analysis are the best indicators of quality.

These figures describe products tested at specific times; brands may change suppliers and formulations, so current testing information is the most relevant guide when choosing a product today.

A Practical Weekly Approach

For someone who wants to keep using protein powder while limiting exposure, a practical approach might look like this: identify how much protein you actually need from a dietitian or reliable guidance; plan meals that provide most of it from foods such as eggs, dairy, fish, poultry, legumes, and tofu; use protein powder only on days when meals fall short or after particularly demanding workouts; choose a third-party tested product, ideally dairy-based if tolerated; and switch between two or three trusted products rather than relying on one. This approach preserves convenience while keeping heavy metal intake from supplements low.

People with specific goals, such as athletes in intense training or older adults with poor appetites, can adapt this approach with professional guidance, balancing the benefits of adequate protein against the small but avoidable exposures that some products add.

Further Reading

Readers who want to learn more can consult Consumer Reports’ published testing, the FDA’s information on dietary supplements and on its Closer to Zero initiative, California’s Proposition 65 resources, and the NIH Office of Dietary Supplements. Independent certification organizations publish their standards, which help consumers understand what each seal covers. Comparing information from testing organizations, manufacturers, and independent scientists gives the most balanced picture.

A Balanced View

Headlines about heavy metals in protein powder can be alarming, but context matters. Trace metals are present in many foods, including vegetables, grains, rice, and chocolate, because they occur naturally in soil. The concern with supplements is that they add to this baseline, sometimes substantially, and that some products contain much more than others. Testing by consumer organizations has helped identify outliers and push manufacturers toward better practices. Using that information to choose products wisely, rather than either ignoring it or abandoning protein supplements entirely, is the most sensible response for most people.

Signs to Talk With a Clinician

Low-level lead exposure usually causes no obvious symptoms, which is why prevention matters. People who have used high-lead products heavily for long periods, especially those who are pregnant, planning pregnancy, or have children who consumed such products, can ask a clinician whether a blood lead test is appropriate. Symptoms associated with higher lead exposure, such as abdominal pain, fatigue, headaches, irritability, memory problems, or high blood pressure, have many possible causes, but a clinician can evaluate them and consider exposure history. For most adult users of protein supplements, the more relevant step is simply choosing lower-metal products going forward.

Clinicians and dietitians can also help people decide whether they need protein supplements at all, which may be the simplest way to reduce exposure for those who can meet their needs through regular meals.

How the Industry Has Responded

After testing reports, some manufacturers have reformulated products, changed ingredient suppliers, published more testing data, or sought third-party certification. Others have disputed the methods or benchmarks used, arguing that comparing products to a very strict daily threshold overstates risk or that per-gram concentrations are comparable to other plant foods. Trade associations have generally emphasized compliance with existing regulations and good manufacturing practices. For consumers, these responses underscore the value of independent testing and transparency: brands that publish detailed, batch-specific data allow shoppers to judge for themselves.

Over time, consumer attention, independent testing, and potential future regulation are likely to push heavy metal levels in protein products downward. Until federal standards exist, informed purchasing decisions remain the most direct way for consumers to influence product quality, and transparent companies that publish their results make those decisions easier for everyone.

If you are unsure whether your current product is a good choice, look up its most recent independent test results, check whether the brand publishes batch-level data, and compare it with alternatives that meet your dietary needs. Small changes, such as switching to a tested dairy-based product or reducing daily servings, can substantially lower exposure without giving up the convenience of protein supplements.

Above all, remember that protein powder is optional for most people, while a varied diet built on whole foods remains the foundation of good nutrition and the most reliable way to meet protein needs with the fewest unwanted extras.

A Note on Collagen Powders

Collagen peptides are often marketed alongside protein powders but lack the essential amino acid tryptophan, so they are not a complete protein and should not be relied on to meet protein needs.

Frequently Asked Questions

Do all protein powders contain heavy metals?

Most contain at least trace amounts because metals occur naturally in soil and water. Levels vary widely between products and protein sources.

Are plant-based protein powders worse?

In Consumer Reports’ 2025 testing, plant-based products averaged about nine times more lead than dairy-based ones. Individual products vary.

Is it safe to use protein powder every day?

Consumer Reports advised against daily use for most products it tested. A risk assessment using other benchmarks found typical use unlikely to pose non-cancer risks. Choosing tested products and limiting servings reduces exposure.

Are there legal limits on heavy metals in supplements?

There are no federal limits in the U.S. California requires Proposition 65 warnings above certain exposure levels.

How can I find a cleaner protein powder?

Look for third-party certifications, check published contaminant testing, prefer dairy-based proteins if you tolerate them, and avoid large-serving mass gainers.

References

1. Food Processing. Consumer Reports Rips Protein Powders, Shakes for High Lead Levels. October 17, 2025. foodprocessing.com
2. NPR via KPBS. A study found lead in popular protein powders. Here’s why you shouldn’t panic. October 2025. kpbs.org
3. Nutraceuticals World. Consumer Reports testing of 23 protein powders. October 15, 2025. nutraceuticalsworld.com
4. Bandara SB, Towle KM, Monnot AD. A human health risk assessment of heavy metal ingestion among consumers of protein powder supplements. Toxicology Reports. 2020;7:1255–1262. PMID 33005567

Last updated: October 6, 2026