Arnold Schwarzenegger is taking a hard look at his supplement shelf. In his July 8, 2026, Arnold’s Pump Club newsletter, he warned of potential heavy metal contaminants in creatine products.
“Do You Know What Else Is In Your Creatine? — Creatine is probably the most studied supplement on the shelf. At this point, it has more than 600 human trials alone across the last three decades.
Creatine works for a variety of health benefits. But there’s a question almost nobody asks on the way to checkout: what else made it into the tub along with it?”
Schwarzenegger has long touted the benefits of creatine, describing it as a low-risk, high-reward supplement. He shared that it can help with muscle gain, fat loss, sleep deprivation, and even cognitive performance.
Through the years, Schwarzenegger has shot down myths around creatine, from bloating to hair loss. Now, he’s discussing what you could be getting from the supplement beyond the listed ingredients.
Arnold Schwarzenegger on Hidden Heavy Metals in Creatine Products
In the newsletter, Schwarzenegger pointed out that contamination in creatine isn’t from the creatine itself.
“After a deep dive into lab reports, we found that contamination in creatine mostly doesn’t come from the creatine. Researchers who’ve traced contaminant sources in commercial creatine supplements point to a specific list of culprits, and most of them are not the ingredient itself.”
He explained that reagents (substances used in chemical reactions), solvents, and processing equipment could contaminate the powder with heavy metals such as mercury and cadmium.
“Some studies point to the reagents and solvents used during synthesis, while others point to the metal tubing and equipment the powder passes through on the production line, or to the containers.”
“Mercury and cadmium turn up because they’re used in plastics manufacturing. Nobody’s adding these on purpose. It’s just what happens when a product moves through a supply chain that wasn’t built with purity as the first priority.”
While Europe regulates many of these heavy metals, the US has yet to adopt similar measures:
“Europe regulates this. EFSA, the EU’s food safety authority, set specific limits years ago on the amounts of arsenic, cadmium, mercury, and lead that a batch of creatine monohydrate may contain. However, the US never adopted anything comparable.”
“The FDA doesn’t require heavy metal testing on supplements at all — which is why we are so so consistent in recommending you only buy supplements with third-party testing — and PFAS and microplastics don’t appear on most brands’ testing checklist, period.”
He shared that eliminating exposure is challenging, but the goal should be to keep it to a minimum.
“Remember, single-serving exposure at those levels isn’t a reason to panic. The goal with heavy metals isn’t zero exposure; it’s limiting exposure where you can, such as by not microwaving food in plastic or drinking from a plastic water bottle daily.”
Schwarzenegger isn’t the only top name in fitness to break down creatine supplementation. ATHLEAN-X founder Jeff Cavaliere recently outlined how creatine works. He also explained why it won’t cause kidney damage.
Creatine continues to prove itself as one of the strongest supplements on the market. Schwarzenegger believes impurities are unavoidable to a degree, which is why it’s important to choose a third-party tested brand.
