Your morning muscle gains may be coming with a side of metal poisoning.
A Consumer Reports investigation released this week found that many protein shakes and powders contain “troubling levels” of toxic heavy metals.
Protein has long been a staple of fitness fanatics and those looking to improve their muscle mass, but recently protein and supplements have broken into the mainstream. It’s more than just powders, shakes and bars; protein has become the latest health phenomenon. From oatmeal, ice cream, chips, pasta sauce — anything you can imagine — hundreds if not thousands of people on the internet have built followings around protein-focused meals and eating. Even the Kardashians jumped on the trend with Khloe recently dropping a line of protein popcorn.
But maybe you should think twice before grabbing that shake or mixing a scoop in your morning oats. Consumer Reports found that as protein popularity has skyrocketed, the presence of lead and heavy metals has only gotten worse.
Of the 23 powders and ready-to-drink shakes that were analyzed, more than two-thirds had heavy metal levels (arsenic, calcium, lead) higher than food safety experts say is safe to consume in a day, some registered as high as ten times over the healthy limit.
“We advise against daily use for most protein powders, since many have high levels of heavy metals and none are necessary to hit your protein goals,” said chemist and food safety researcher Tunde Akinleye in the research report.
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Lead was the most commonly reported metal with 70% of the products exceeding 120% of Consumer Report’s concern (0.5 micrograms per day). The study found that plant-based protein products had nine times the amount of lead, on average, compared to dairy-based or beef-based products.
Fifteen years ago, Consumer Reports conducted another study of heavy metal in protein powders. At that time, researchers said there were fewer products with detectable metal levels, and even the largest outliers had reported less than half the levels they are reporting now.
If you have been regularly using these products, experts say not to panic. Even those that tested at the highest levels are far below the concentration that would cause immediate harm. However, you should consider lowering your use to occasionally or swapping powders for more natural protein altogether.
