Optimal - The Blog

January 30, 2025

Avoid Excess Heavy Metals in Protein Powders

Recent analyses by Consumer Reports and the Clean Label Project have revealed that all tested protein powder supplements contain heavy metals such as arsenic, cadmium, mercury, and lead, potentially surpassing the safety limits established by the U.S. Pharmacopeia.

Plant-based protein powders are particularly concerning, with 70-74% of these products showing measurable levels of lead and cadmium, and organic plant-based options frequently containing more than twice the heavy metal content of their non-organic counterparts.

Source: Bandara, Suren B et al. “A human health risk assessment of heavy metal ingestion among consumers of protein powder supplements.” Toxicology reports vol. 7 1255-1262. 21 Aug. 2020, doi:10.1016/j.toxrep.2020.08.001 This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

This contamination primarily originates from the ingredients used in these supplements, as plants absorb heavy metals from their environment—air, water, and soil—which persist in the final product even after processing. Similarly, whey protein can be contaminated if the source of milk is polluted. Mass gainer supplements exhibit exceptionally high hazard indices due to elevated arsenic and cadmium levels, posing significant health risks such as kidney disease, thyroid problems, weakened bones, skin lesions, and various toxic effects on the nervous, reproductive, and cardiovascular systems.

Although studies suggest that the non-carcinogenic risks associated with protein powder consumption are generally below harmful levels, the elevated hazard indices in some mass gainer products still present potential health threats.

To mitigate the risk of heavy metal exposure, it is advisable to use protein powder supplements in moderation, limiting intake to about one 30-gram serving per day. When possible, consumers should prefer animal-based protein powders over plant-based ones and select reputable brands that thoroughly test contaminants.

Additionally, being informed about the sources and types of protein powders can help individuals make safer choices, reducing their exposure to harmful heavy metals while still benefiting from protein supplementation.