For most of my years on this earth, heavy metal has had nothing to do with food and everything to do with Black Sabbath and teen angst. But recently, the term has taken on a more concerning timbre. Thanks to years of research by public health, consumer, and government experts, studies have revealed elevated levels of arsenic, lead, mercury, and cadmium in a wide variety of baby foods—those generally marketed for children aged two and under.
Heavy metals, which include those listed above as well as zinc, iron, and others are so prevalent in our soils and waterways—naturally, and due to human activities such as mining and pesticide use—that it’s inevitable that they’re taken up by plants we eat. Even in small quantities, lead, arsenic, mercury, and cadmium are known to pose a risk of neurological and developmental impairment in children, who are still growing and eat more food proportional to their body weights than adults do.
In November, a slew of products were recalled when the US Food and Drug Administration (FDA) cited 86 confirmed cases of lead poisoning after (mostly) children ate certain brands of apple purée likely spiked with contaminated cinnamon. This past June, Consumer Reports testing found concerning levels of arsenic, cadmium, and lead in baby food products, particularly those made with rice, sweet potatoes, and, to a lesser extent, carrots. (Elevated levels of heavy metals have also been found in fruit juice, chocolate, and more.) And in February 2021, the US House Oversight and Reform Subcommittee on Economic and Consumer Policy released a 59-page report declaring various packaged baby foods tainted with “dangerous levels” of heavy metals.
The slew of findings have “shed light on how little regulation has been in place for setting industry standards,” says Maya Deyssenroth, DrPH, an assistant professor of environmental health sciences at Columbia University. Though the FDA has only recently started setting stricter standards for heavy metals specifically found in baby foods, the agency does seem to be tightening guidelines for manufacturers in the US.
With California Assembly Bill 899 recently being signed into law by Governor Gavin Newsom, baby foods produced in the state started requiring heavy metal testing before sale as of January 1. Minimizing these heavy metals in the diet, particularly those of kids, has also become an apparent federal priority. The FDA sets action levels for contaminants, like heavy metals, in various foods, defining the maximum permissible amount before federal intervention. While the agency regulates metals like lead in bottled water, it only recently proposed limits for baby and toddler foods. (The exception is arsenic in rice cereal. The FDA set a limit of 100 ppb in 2021, prompting immediate criticism for being not stringent enough to protect vulnerable populations; the European Commission, by comparison, only allows 0.1 ppb or arsenic in “rice destined for the production of food for infants and young children.”)
Earlier this year, as part of its Closer to Zero campaign—a bid to reduce childhood exposure to contaminants—the FDA proposed draft guidance, which, if adopted, would allow the agency to take action against companies that sell products containing more than 10 to 20 parts per billion (ppb) of lead. (For reference, 10 ppb is equal to 10 micrograms per liter/kilogram—think of it like one second in 32 years or one sugar cube dissolved in a swimming pool.) Action plans for arsenic, cadmium, and mercury won’t be announced until 2024 at the earliest.
Still, the Centers for Disease Control and Prevention (CDC) has said there’s no safe level of lead for children—even trace amounts, when consumed over time, can have lifelong consequences. And the FDA’s draft guidance has drawn criticism for being too soft on manufacturers, essentially codifying the industry standard. “These [proposed] levels are not low enough to protect kids,” says Jane Houlihan, the research director at Happy Babies Bright Futures (HBBF), which has extensively researched heavy metals in infant and toddler foods.
According to an FDA spokesperson, the FDA goes through “a thorough process” to set its action levels, seeking to “understand the levels of contaminants in the food supply, the potential for health risks from dietary exposure to the contaminant, and what levels are feasible for industry to achieve.” The spokesperson says the draft lead guidance also includes a tenfold safety factor, meaning that it’s proposed 10 to 20 ppb is nearly 10 times less than the actual amount of lead intake from food that would be required to reach the Center for Disease Control and Prevention’s (CDC) blood reference level (the level at which CDC recommends health care providers monitor children).
In lieu of widespread legislation governing food companies, experts say there are plenty of strategies parents can deploy to minimize their children’s exposure to these contaminants. Here’s what to know about heavy metals in baby foods.
What are heavy metals?
The term refers to naturally occurring elements in our environment that are typically present in very small amounts. The heavy designation is literal: The metals we’re talking about have “a relatively high density compared to water,” says Deyssenroth. There are numerous heavy metals, but in a dietary context, four are considered to pose significant human health risks—lead, arsenic, cadmium, and mercury. (Though arsenic is technically a metalloid, meaning it’s both metal and non-metal, it’s typically grouped in with the heavy metals based on similar levels of concern.)
Not all heavy metals are toxic to human health, and some—like iron, zinc, and manganese—are actually “essential nutrients at low doses,” says Deyssenroth. Even the toxic ones are only so in certain amounts and over time. Technologies used to measure heavy metals in foods have become way more precise over the years, says Joe Zagorski, PhD, a toxicologist at Michigan State University’s Center of Research on Ingredient Safety, which means we can discover even miniscule amounts now. “But simply detecting a contaminant in our food supply doesn’t mean the food becomes unsafe,” he says.
How do heavy metals end up in food?
Heavy metals have existed in the earth’s crust since prehistory—meaning, as rocks weather and erode, these metals end up in the soils and waterways that we use to grow food. Human activities can also increase heavy metal concentrations. “For example, crops can absorb arsenic leached into soil from [human-made] pesticides used in agricultural practices or they can be introduced via food packaging during industrial production,” says Zagorski. Mining also tends to contaminate the surrounding soils and waterways with an excess of heavy metals.
To the foods we eat, the source or the type of heavy metal doesn’t matter. “Plants and organisms do not differentiate between naturally occurring or human-made compounds,” says Zagorski. “They will take up whatever is in their environment and whatever they can absorb.” And they do so at different rates: Rice is a known arsenic sponge, for example, and spinach sucks in more cadmium than other plants.
What are the health effects associated with eating heavy metals?
Research has found heavy metals in protein powder, root vegetables, spices, bone broth, leafy greens, and more. What we don’t really know is how dietary sources alone impact people. Most of what we understand about how heavy metals influence health is extrapolated from biomarkers, such as measurable levels in urine or blood. These tests “integrate exposure from all sources and often reflect exposure over a period of weeks or years, meaning we cannot easily attribute a harmful effect to diet,” says Katarzyna Kordas, an associate professor of public health at the University of Buffalo. This knowledge gap is important, because nutrients found in food may, for example, “counteract the absorption or toxicity of such metals.”
Still, we know that ingesting heavy metals is related to various health effects. (Recently, podcaster Joe Rogan had elevated arsenic levels in his blood after eating too many sardines, which are known to contain the compound.) While an excess is not good for anyone, kids are particularly vulnerable to heavy metals. For example, they absorb four to five times as much lead as adults. Consumption of lead and arsenic has also been shown to negatively impact neurological development. And “depending on how long children are exposed to these toxins and how much they are exposed to, they may be at risk for lowered IQ, behavioral problems (such as attention deficit hyperactivity disorder), type 2 diabetes, and cancer, among other health issues,” according to a Consumer Reports study on heavy metals in apple juice. Each contaminant comes with its own specific risks too.
Arsenic, which occurs naturally but can also concentrate in water supplies due to pesticide use, is both likely carcinogenic and linked to cardiovascular issues. In adults, excessive lead exposure (from car exhaust, pesticides, battery manufacture, and more) can cause high blood pressure, along with brain, kidney, and reproductive issues. Too much cadmium (which might have come from tin, paint, and zinc manufacturing, along with tobacco smoke and rechargeable batteries) increases the likelihood of bone damage and kidney disease, among other issues. And, as stated on the Environmental Protection Agency’s website, children exposed to mercury “while they are in the womb can have impacts to their cognitive thinking, memory, attention, language, fine motor skills, and visual spatial skills.”
Which foods tend to contain the most heavy metals?
“It will depend on the metal,” says Kordas, as well as “the geographical area where food crops are grown because many metals are quite common in some soils” but less so in others. It’s also important to keep in mind that there’s no perfect food. “Many nourishing foods have trace amounts of metals but the nutritional benefits of these foods often outweigh any risk of heavy metal exposure,” says Venus Kalami, MNSP, RD, CSP, a pediatric dietician and nutritionist at Solid Starts, a child feeding resource.
Researchers at HBBF also tested hundreds of different foods for heavy metals. After analyzing the varying concentrations of contaminants in each, the organization advises parents to consider the following rotational framework when meal planning for babies. It’s broken foods down, based on their metal contents, into four categories:
- Serve (eat freely): HBBF suggests serving ample fresh/frozen fruit; vegetables, including green beans, peas, and butternut squash; eggs, meats, beans, cheeses, and yogurt; and infant formula (made with lead-free water).
- Limit or rotate (eat less than daily): The organization suggests eating various foods less often. These include cantaloupe and canned fruit; root and tubers, like sweet potato, potato, and carrot; leafy greens, such as baby spinach; a variety of non-rice grains like oatmeal, barley, millet, and farro (serving different ones each day); some 100% fruit juices; and non-rice teething biscuits and crackers.
- Serve rarely (high in heavy metals): HBBF recommends avoiding ingredients like dried fruit; mature spinach (baby spinach is safer); sunflower seed butter; grape juice; oat ring cereal; and rice-based teething biscuits and arrowroot teething crackers.
- Avoid (highest in heavy metals): According to the organization, parents should try to skip the crisped rice cereal, brown rice cooked with no extra water used, and rice puffs and rice cakes.
The general guidance for feeding children, according to various experts I spoke with, is to provide a decent variety of ingredients. “This broad guidance holds well for reducing children’s dietary exposure to heavy metals,” says Kordas. “By offering different foods on a daily or weekly basis, we lower the contribution of any one food to heavy metal exposure.”
While most heavy metals testing is done using packaged goods, further research by HBBF also found that homemade baby foods are “just as likely to be contaminated with heavy metals,” says Houlihan, the organization’s research director. And, because the primary dietary sources are soil and water, even organic foods aren’t necessarily any better.
How else can parents minimize exposure?
Researchers are working to reduce the heavy metal load in our foods, says Deyssenroth, citing several strategies still under development to prevent crop uptake of heavy metals present in the environment. “For example, certain strains of bacteria and vegetation show the potential to sequester contaminants present in soil,” she says. “Alternatively, crops may be genetically engineered to block absorption of heavy metals.” But these findings are still years away from becoming reality, and in the near term, personal exposure reduction is still the best way to protect your family. According to experts, here are some other ways to do so:
- Buy from trusted brands: Shopping for products certified by the Clean Label Project “would be my first recommendation,” says Cinthia Scott, RD, IBCLC, a pediatric dietitian, lactation counselor, and owner of The Baby Dietitian. The organization purchases foods at retail outlets and tests them for heavy metals, as well as pesticide residues and plasticizers.
- Focus on overall nutrition: “Ensure your child is consuming adequate amounts of calcium, zinc, and iron, which can help reduce the amount of toxic metals absorbed into your child’s body,” says Scott.
- Encourage proper hand hygiene: Have kids wash their hands thoroughly before meals, says Scott, “to reduce the risks of heavy metal contamination from dirt or soil that may be present on their [skin].”
- Test your drinking water: “This continues to be a potentially important source of exposure to lead among children in the United States,” says Kordas. “Periodically asking your utility to test water or sending your well water for tests is a good idea.”
- Go to regular checkups: Though not all blood metal levels can be easily determined, lead is one exception, and parents can ask doctors to test for it. “A finger prick is performed, and the results are available within minutes,” says Kordas.
- Make simple food swaps: For example, replace teething biscuits (especially anything rice based) with frozen bananas or chilled cucumber, swap canned fruit for the fresh or frozen stuff, and go with infant oatmeal instead of rice-based cereals.
- Cook with heavy metals in mind: Vegetable skins are a great source of fiber and antioxidants. But peeling sweet potatoes and carrots specifically tends to lower their heavy metal risks. Also, cooking rice like pasta (in lots of water) reduces the amount of arsenic present, and scrubbing all fruits and vegetables under running water can remove some surface metals.
Though reducing heavy metal exposure can feel overwhelming, Kalami, the pediatric dietician, says it’s important to remember that the nutritional benefit of many baby foods outweigh the risks of serving them. She says, “The key is to focus on variety.”