Over the years, there have been reports on dangerous levels of heavy metals in protein powders. The latest scary headline reads: “Lead and Cadmium Found in Muscle-Building Protein Powders, Report Says.”[1]
Headlines like this increase fear around consuming protein powders and raise questions from consumers. As a brand that sells protein powders, we get a lot of questions about heavy metals in our products when headlines like this are released. It’s always a good idea to take charge of your health by investigating the products you use, and we’re so happy to field these questions when they come in!
Heavy metals, like other topics in nutrition, involve nuance and context. Today’s article will take a deep dive into heavy metals, why they show up in protein and other foods, and how you can minimize your exposure. We’ll cover:
- The latest protein powder report
- What are heavy metals?
- Heavy metals and the food supply at large
- How to protect yourself as a consumer
- Why you can trust Outwork Nutrition Build Whey Protein
The Latest Report on Protein Powders and Heavy Metals
The Clean Label Project 2024-25 Protein Powder Category Report tested 160 protein powders from 70 top-selling brands. The sample represents 83% of the protein powder market. Investigators tested the protein powders for purity and contamination, including lead, cadmium, arsenic, and mercury.[2]
The report revealed that 47% of the samples had heavy metal contamination that exceeded California’s Prop 65 standards, which are the strictest standards for heavy metal limits in food, much more stringent than federal regulations. In California, products that don’t meet Prop 65 standards must carry a warning label.[2]
However, when we look closer at the results, we can see that not all protein powders carry the same risk of heavy metal contamination. For example, 77% of plant-based protein powders tested over Prop 65 levels for lead, compared to 28% of whey protein powders. On average, plant-based protein powders contain nearly 3 times more lead than whey powders.[2]
Flavorings in the powders matter, too. For example, 65% percent of chocolate protein powders tested over the Prop 65 threshold for lead. Chocolate-flavored powders are the highest risk for heavy metal content across all protein powders.[2]
The findings of this report are not new; the reported heavy metal contamination is similar to other investigations over the years. Yet, the report calls for stricter safety standards to protect consumers and to increase transparency with protein powder and supplement companies.
What Are Heavy Metals?
Heavy metals, including lead, cadmium, mercury, aluminum, and arsenic, are natural elements found in the Earth’s crust. Although they are naturally occurring, heavy metals can concentrate in our environment due to human activities like industrial processing and some agricultural practices. Heavy metals are found in soil, water, air, plants, and indoor dust, which make their way into animals and humans.[3]
At high amounts and long durations of exposure, heavy metals can cause toxic health effects. For example, arsenic is carcinogenic and poisonous. Mercury poisoning can lead to neurological disorders. Lead increases oxidative stress, affecting the nervous and reproductive systems. Infants and children are particularly vulnerable; too much lead exposure can impact brain development and lower IQ.[3][4]
Heavy Metals in the Food Supply
The hard truth is that, because heavy metals are in the environment – air, water, and soil – they are in the food supply. Plants take up heavy metals, like they do nutritious minerals, from the soil they grow in. Nearly all foods, including the produce you buy at the grocery store, contain some trace amounts of heavy metals.
Because heavy metals are in plants, when you concentrate all that plant matter into a powder, the heavy metals will also concentrate. This is why many plant-based protein powders test high in heavy metals. Heavy metals can also get into products via the manufacturing process or packaging.[2]
Certain foods will also have an affinity for certain metals or may come from an environment high in a particular heavy metal. For example:
Heavy metal contamination is not a problem unique to protein powders; it’s a widespread issue in our food supply.
Putting Heavy Metals in Context
Heavy metals are found in nearly all food, yet we aren’t hearing the advice to stop eating fruits or vegetables. Heavy metals are in drinking water, but we aren’t told to stop drinking water. In many cases, the benefit of the food outweighs the risk, especially when you put it in the context of who is eating the food (is it an adult or infant?) and how much they are eating (is it a tiny amount occasionally?).
Your personal health and nutrition habits also play a role in heavy metal absorption. Just because a contaminant goes into your mouth doesn’t automatically mean it will get into your body.
Research shows that a high-fiber diet blocks heavy metal absorption because the metals bind to fiber and you excrete them via the colon.[8][9]
Further, your mineral status helps prevent the absorption of heavy metals because minerals compete for absorption. Research suggests that calcium, zinc, and iron deficiencies can lead to increased absorption of heavy metals, especially cadmium and lead. So, an overall healthy eating pattern, rich in plant foods and healthy minerals, is protective against heavy metals in the body.[10][11]
Achieving zero heavy metals in food is impossible. Still, it is good for consumers to be aware of food sources that have a higher likelihood of contamination, especially those that are consumed frequently.
Outwork Nutrition Protein Powder
At Outwork Nutrition, we pride ourselves as a transparent brand. We are aware of the heavy metal issue, and so we 3rd party test all our products for heavy metals and other contaminants to ensure the safest possible products.
Our whey protein, Build, uses 100% whey isolate powder, which contains zero heavy metals. Additionally, we test our finished products with 3rd party labs to verify heavy metal content.
Vanilla, Strawberry, Cookies & Cream, and Unflavored contain no detectable levels of heavy metals.
Chocolate and Peanut Butter Cup contain trace amounts due to the chocolate and peanuts used for flavoring, but they are well below Prop 65 limits.
Key Takeaways
- Heavy metals are a natural part of the environment and impossible to avoid. Everyone is exposed to trace amounts of heavy metals in plant foods.
- Plant-based protein powders are the highest risk for heavy metal content, due to the heavy metals that plants naturally absorb from growing in the soil.
- Chocolate flavors are the highest risk for heavy metal content across all protein powders (which makes sense, since cocoa beans come from plants).
- Outwork Build uses 100% whey isolate powder, which contains zero heavy metals. Additionally, we test our finished products with 3rd party labs to verify heavy metal content. Any heavy metals detected (in flavors like Chocolate) are well below Prop 65 limits.
When you need a safe, high quality protein powder for daily use, Outwork Nutrition Build has you covered!
➡️ SHOP NOW
References
1. https://www.cnn.com/2025/01/09/health/protein-powder-heavy-metals-wellness/index.html
2. https://cleanlabelproject.org/protein-study-2-0/
3. Jaishankar, Monisha et al. “Toxicity, mechanism and health effects of some heavy metals.” Interdisciplinary toxicology vol. 7,2 (2014): 60-72. doi:10.2478/intox-2014-0009
4. Papanikolaou, Nikolas C et al. “Lead toxicity update. A brief review.” Medical science monitor : international medical journal of experimental and clinical research vol. 11,10 (2005): RA329-36.
5. Zheng, Na et al. “The Toxicological Effects of Mercury Exposure in Marine Fish.” Bulletin of environmental contamination and toxicology vol. 102,5 (2019): 714-720. doi:10.1007/s00128-019-02593-2
6. Mawia, Amos Musyoki et al. “Inorganic arsenic toxicity and alleviation strategies in rice.” Journal of hazardous materials vol. 408 (2021): 124751. doi:10.1016/j.jhazmat.2020.124751
7. Abt, Eileen, and Lauren Posnick Robin. “Perspective on Cadmium and Lead in Cocoa and Chocolate.” Journal of agricultural and food chemistry vol. 68,46 (2020): 13008-13015. doi:10.1021/acs.jafc.9b08295
8. Román-Ochoa, Yony et al. “Specific dietary fibers prevent heavy metal disruption of the human gut microbiota in vitro.” Food research international (Ottawa, Ont.) vol. 176 (2024): 113858. doi:10.1016/j.foodres.2023.113858
9. Guo, J., et al. "Dietary Fiber Intake Is Inversely Related to Serum Heavy Metal Concentrations Among US Adults Consuming Recommended Amounts of Seafood: NHANES 2013-2014." Food Frontiers, vol. 3, 2022, pp. 142–149. https://doi.org/10.1002/fft2.114
10. Peraza, M A et al. “Effects of micronutrients on metal toxicity.” Environmental health perspectives vol. 106 Suppl 1,Suppl 1 (1998): 203-16. doi:10.1289/ehp.98106s1203
11. Zhai, Qixiao et al. “Dietary strategies for the treatment of cadmium and lead toxicity.” Nutrients vol. 7,1 552-71. 14 Jan. 2015, doi:10.3390/nu7010552
