Protein supplements are hugely popular worldwide, transforming what was a niche product into the centrepiece of a multibillion-dollar wellness craze, driving booming sales and spawning a new crop of protein-fortified foods that now saturate supermarket shelves and social media feeds.
However, recent tests in the US of 23 of these products found that more than two-thirds of them contain more lead in a single serving than experts say is safe to have in a day – some by more than 10 times.
According to Consumer Reports (CR), protein powders still carry troubling levels of toxic heavy metals, and these latest tests of powders and ready-to-drink shakes found that this contamination has become even more common, raising concerns that the risks are growing right alongside the industry itself.
“It’s concerning that these results are even worse than when we tested more than a decade ago,” said Tunde Akinleye, the CR food safety researcher who led the testing project.
In addition to the average level of lead being higher than what was found 15 years ago, there were also fewer products with undetectable amounts of it. The outliers also packed a heavier punch. Naked Nutrition’s Vegan Mass Gainer powder, the product with the highest lead levels, had nearly twice as much lead per serving as the worst product that had been analysed in 2010.
Nearly all the plant-based products CR tested had elevated lead levels, but some were particularly concerning. Two had so much lead that CR’s experts caution against using them at all. A single serving of these protein powders contained between 1 200% and 1 600% of CR’s level of concern for lead, which is 0.5 micrograms per day.
Two others had between 400% and 600% of that level per daily serving. CR experts recommend limiting these to once a week.
The lead levels in plant-based products were, on average, nine times the amount found in those made with dairy proteins like whey, and twice as great as beef-based ones.
Dairy-based protein powders and shakes generally had the lowest amounts of lead, but half of the products still had high enough levels of contamination that CR’s experts advise against daily use.
While many of these powders are fine to have occasionally, and even those with the highest lead levels are far below the concentration needed to cause immediate harm, because most people don’t actually need protein supplements – nutrition experts say the average person already gets plenty – it makes sense to ask whether they are worth the added exposure.
Consumers often assume supplements deliver health benefits without risks, said Pieter Cohen, MD, an associate Professor of Medicine at Harvard Medical School. “But that’s not true.”
CR’s experts agree. “For many people, there’s more to lose than you’re gaining,” said Akinleye, who suggests that regular users of protein supplements consider reducing their consumption.
The FDA doesn’t review, approve, or test supplements like protein powders before they are sold. Federal regulations also don’t generally require supplement makers to prove their products are safe, and there are no federal limits for the amount of heavy metals they can contain.
While no amount of lead is technically safe, the greatest danger comes from repeated or continuous exposure, particularly at high doses, said Rose Goldman, MD, an associate Professor of Medicine and Physician at Cambridge Health Alliance in Massachusetts.
Children and pregnant people are most vulnerable because lead can damage the developing brain and nervous system, which has the potential to cause neurological issues, learning delays, and behavioural problems.
But chronic lead exposure has also been linked to immune suppression, reproductive problems, kidney damage, and high blood pressure in adults.
Lead lingers in the body, so even small amounts can add up over time and contribute to health risks, Goldman said. And unlike some other foods CR has tested for heavy metals, such as chocolate and bubble tea, protein powder isn’t usually treated as an occasional indulgence.
For many people, it’s part of their daily routine. Some products are even marketed as complete meal replacements, with superfans bragging in online forums about surviving on nothing but these powders for weeks or months at a time.
Compounding the problem is the exploding popularity of protein-fortified foods, snacks, and beverages, which are designed to supplant conventional foods in regular everyday diets but are frequently made with the same problematic ingredients as the supplements.
And concerningly, with these types of products so easily available online, they’re not just restricted to American consumers, but are accessible to anyone anywhere, including in South Africa.
What CR’s tests found
For its tests, CR selected a range of bestselling dairy, beef, and plant-based protein supplements, including protein powders and ready-to-drink protein shakes, buying the products from various sources, including popular online retailers like Amazon and Walmart, and at supermarkets and health shops.
Then the lab tested samples from multiple lots of each product for total protein, arsenic, cadmium, lead, and other elements. Because the results are based on an average of these samples, which were collected over a specific period of time, they may not mirror current contaminant levels in every product.
Even so, the findings highlight why consumers should carefully consider the role of protein powders and shakes in their diet.
All products met or exceeded their label claim of protein in the tests, offering between 20 to 60 grams of protein per serving.
Lead was the main heavy metal that emerged as an issue.
About 70% of the products contained more than 120% of CR’s level of concern for lead, which is 0.5 micrograms per day. Three products also exceeded the level of concern for cadmium and inorganic arsenic, toxic heavy metals that have been classified as a probable human carcinogen and known human carcinogen, respectively, by the Environmental Protection Agency.
Two plant-based protein powders contained enough lead that the experts advise against consuming them. Naked Nutrition’s Mass Gainer powder contained 7.7 micrograms of lead per serving, which is roughly 1 570% of CR’s level of concern for the heavy metal.
One serving of Huel’s Black Edition powder contained 6.3 micrograms of lead, or about 1 290% of CR’s daily lead limit.
Two other powders contained lead between 400% and 600% of CR’s level of concern: Garden of Life’s Sport Organic Plant-Based Protein and Momentous’ 100% Plant Protein. Consumers should limit these to once a week, Akinleye says.
The only non-plant-based protein powder with lead detected at more than 200% of CR’s level of concern powder.
Six additional plant-based powders, five dairy-based powders and shakes, and one beef powder contained lead above CR’s level of concern.
Consumer Reports article – Protein Powders and Shakes Contain High Levels of Lead (Open access)
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