It’s no secret that protein is big business right now. Browse the shelves of your local supermarket and you’ll see just how many products tout their protein content, whether it’s from natural sources, such as meat and milk, or in more processed items, like breakfast cereals and pasta.
And for anyone looking to supplement their protein intake or get it from non-animal sources – gym users or vegans, for example – there are protein powders.
But a worrying new report has identified another substance, besides protein, hiding in some of these powders: lead. Given this news, just how worried should you be about your protein powder?
Lead levels
Consumer Reports, an independent nonprofit organisation based in the US that assesses the quality of consumer products, tested the makeup of 23 protein powders and shakes.
Their results, published in October, were shocking – over two-thirds of the products contained more lead in a single serving than Consumer Reports’ food safety experts consider safe to consume in a day.
More worrying still, a single serving of some of the products contained as much as ten times Consumer Reports’ dietary consumption limit.
On the face of it, these sound like extremely unsafe amounts of lead to find in a product intended for human consumption. It’s worth noting, however, that Consumer Reports sets its daily dietary consumption limit relatively low: 0.5 micrograms (μg) per day. In contrast, the US Food and Drug Administration’s (FDA) daily dietary consumption limit is 12.5μg per day.
Why such a huge disparity between these recommendations? “My guess is that Consumer Reports uses much lower benchmark levels than the FDA because they’re filling a regulatory gap,” says Dr Kathrin Schilling, assistant professor of environmental health sciences at Columbia University, in the US.
That regulatory gap exists in the US because supplements like protein powders aren’t classed as food or drugs. They’re classed as dietary supplements and governed by a different set of FDA regulations, the Dietary Supplement Health and Education Act of 1994 (DSHEA).
“Supplements in the US don’t have federal limits for heavy metals, and manufacturers aren’t required to prove their products are safe before they reach the market,” says Schilling. “Given that science shows there’s no safe level of lead [consumption], Consumer Reports may have set its own targets based solely on health protection.”
In the UK and Europe, however, protein powders are classed as food products, not dietary supplements as they are in the US. That means companies must follow standard food-safety laws, including routine testing for contaminants. But does this guarantee that UK protein powders contain no lead?
“No,” says Schilling. “Even with stricter oversight, trace levels can still appear.”
The dangers
As Schilling states, there’s no safe level of lead. This is according to both the World Health Organization (WHO) and the environmental-health research that Schilling has been a part of.
Exposure to the toxic heavy metal can severely impact the brain, heart, liver and kidneys, and the harm it can cause has been extremely well documented.
For example, a major US study published in The Lancet Public Health journal measured the blood lead levels of 14,000 adults over the course of 20 years. Researchers found that people with the highest blood lead levels were 37 per cent more likely to die from any cause than people with the lowest lead levels, and 70 per cent more likely to die from heart disease.
Similarly, the WHO estimated that in 2019, overexposure to, or overconsumption of, lead contributed to more than 300,000 stroke deaths worldwide.
This is because lead damages the inner lining of blood vessels, which can cause inflammation, plaque buildup and high blood pressure. It’s for this reason that the American Heart Association lists lead as a risk factor for cardiovascular disease.
Other than the damage it can cause, one of the reasons why lead is so deadly is it can stay in the body for a long time.
“Once lead enters the body, it accumulates in bones, teeth and other tissues,” says Schilling. “It can then remain locked in the skeleton for 10–30 years, steadily leaking back into the bloodstream over time.”
This, unfortunately, compounds with the fact that it doesn’t take a lot of lead to damage the body. Even when people are only consuming microgram amounts of lead each day, studies have linked this to a higher risk of developing heart disease, kidney problems and high blood pressure.
And, as previously mentioned, the body removes lead extremely slowly. So, even tiny, daily amounts of it accrue faster than they diminish.
Metal detecting
Consumer Reports’ testing also found that the two protein powders with the highest lead content (up to 6.3μg and 7.7μg per serving) were plant-based products.
“There’s a good scientific reason why some plant-based protein powders showed higher metal levels,” says Schilling.
“Crops like peas, soy and hemp naturally take up metals from the soil. If the soil or irrigation water contains even small amounts of lead, the plants absorb it as they grow.
“When those plants are processed, the metals that were in the original plant become concentrated in the final protein powder. So, the pattern Consumer Reports found is plausible. Their investigation only looked at 23 products, however. We don’t know where the crops were grown or how the powders were manufactured.”
We absorb lead from our environment in a similar way to plants and, unfortunately, decades of industrial lead use in paint, fuel, pipes and other materials have left residues that still enter our food, water and air today.
“Lead remains in soil, dust and old infrastructure,” Schilling says. “It can still find its way into our homes, water and food. And because it’s so widespread in the environment, achieving absolute zero exposure is nearly impossible.”
In fact, a 2019 study by the FDA estimated that the average American adult is exposed to up to 5.3μg of lead each day through their diet alone. If you unknowingly added a scoop of high-lead protein powder to this amount, you could easily be exceeding the FDA’s limits without realising it.
Worse news still, according to Schilling, protein powders in the US have been known to have high lead levels for years. “Reports like this have come out before, but little has changed,” she says. “So, this isn’t just about one brand or one batch. It’s a systemic problem of contamination and oversight.”
So, given all of the above, just how worried should we be about lead in protein shakes and powders?
“Protein powder is just one piece of the puzzle,” says Schilling. “The key message isn’t to panic over a single shake, but to recognise that small amounts of lead from multiple sources add up and that we need stronger oversight to keep lead out of the products people use every day.”
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