Why do so many foods contain lead? How much is safe? Experts explain.
The amount of lead in food is under the microscope after the Food and Drug Administration proposed tighter limits on levels of the metal in processed baby food.
In a press release, the FDA announced plans to reduce lead in foods to under 10 parts per billion (ppb) for fruits, vegetables, yogurts, custards and single-ingredient meats, along with limits of 20 ppb for root vegetables and dry infant cereals. Lead has been linked with a slew of serious health issues in children, which prompted the reduced limits, the FDA says.
The move has gotten a lot of attention — and raised questions about lead in food in general. So, how does lead get into food, and what can you do to limit your exposure? Here's what you need to know.
First, here's why there's lead in your food.
It's important to note up front that food manufacturers aren't deliberately adding lead to their products. The metal can get into food in various ways. First, it simply seeps into the ingredients naturally. "Lead is naturally found in the Earth’s core," Katie Boss, a pediatric dietician at Helen DeVos Children’s Hospital, tells Yahoo Life, pointing out that it can be in the soil that foods are grown in.
"Lead in the food chain comes mostly from direct deposit from the air to plants and from livestock eating soil laced with lead as they eat the plants," Darin Detwiler, an associate professor of food safety at Northeastern University, tells Yahoo Life. "Plants and animals can absorb lead from their environment, meaning that when these plants — such as fruits, veggies and grains — are harvested for food and when animals are slaughtered for their meat, traces of lead remain present."
Lead "gets into all food," Detwiler says, but baby food can have increased levels if manufacturers add vitamins or enzymes to a product. He cites a 2021 congressional report that found many baby foods in the United States — including organic brands — were contaminated with lead and other heavy metals, including cadmium and arsenic. "The levels found were higher than those allowed for other products, like candy and bottled water," he points out.
Lead can also leach into food from industrial processing or packaging, Dr. Diane Calello, executive medical director of the New Jersey Poison Control Center, tells Yahoo Life. "Historically, lead was found in the lining of food cans, but that was, fortunately, phased out decades ago," she says.
How much lead is considered "safe"?
In a perfect world, adults and children wouldn't be exposed to lead. However, it's everywhere in the environment. The World Health Organization (WHO) specifically notes that there is "no known safe blood lead concentration," and that even blood lead concentrations as low as 3.5 µg/dL (micrograms per deciliter) can lead to decreased intelligence, behavioral issues and learning problems in kids.
However, the Centers for Disease Control and Prevention (CDC) recommends that children have blood level concentrations below 5 µg/dL. Anything above that can indicate that lead levels may be unsafe for children, according to the Mayo Clinic. For adults, less than 10 µg/dL is considered normal. A simple blood test can detect the amount of lead in the blood.
Why is lead so harmful for babies and young children?
The focus on lead exposure for babies and young children is greater because they absorb four to five times as much ingested lead as adults from any given source, according to WHO. Kids also tend to put things in their mouths, raising the risk that they'll swallow things that contain or are coated with lead, such as contaminated soil, dust or flakes from paint, per the WHO.
"In the short term, kids would have to have a pretty high lead level to be symptomatic," Dr. Danelle Fisher, a pediatrician and chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, Calif., tells Yahoo Life. "Kids will complain about things like abdominal pain, headaches and dizziness." However, most children can have elevated lead levels and have no symptoms, which is why the American Academy of Pediatrics (AAP) recommends that kids be screened for lead exposure between the ages of 12 and 24 months old.
Over the long term, lead can cause neurocognitive deficits, leading to lower IQ, a decreased ability to pay attention and underperformance at school, the CDC says.
"Lead can be damaging to the developing brain," Calello says. "While adults can have effects from excess lead exposure as well, the effects are more severe in children and occur at lower levels."
How can you avoid lead in food for both adults and babies?
Dr. Sarah Shafer, assistant professor of emergency medicine at Baylor College of Medicine, tells Yahoo Life that parents shouldn't panic about lead in foods, but should be aware that it's there. "Significant lead exposure in processed foods is uncommon, because of FDA monitoring and regulations regarding foods produced and imported into the U.S.," she says.
Detwiler agrees that it can be tough to get rid of all lead in food. "Avoiding lead exposure from foods is rather difficult, as parents have little means of detecting or preventing its presence, beyond knowing where the product comes from and relying on certifications and declarations of lower detected lead levels," he says.
Still, lead is in some foods children are consuming, which is why Fisher recommends being smart about what you feed your child. "When it comes to baby food, we want variability," she says. "No baby should eat only one food. If you vary the types of foods that your baby gets, you won't have so much exposure to lead."
Fisher suggests giving your child a combination of grains, fruits, vegetables, protein and dairy. "When we do that, baby is not going to have an increase in their lead level just from the food they eat," she says. "But if you're constantly giving baby rice cereal three times a day, which can have higher degrees of lead, they will have higher exposure than if you gave it to them once a day."
Detwiler stresses that the biggest sources of unsafe lead exposure for children are often from the environment. The CDC flags these sources in particular for parents to be wary of:
Paint in homes built before 1978 that is deteriorating or chipping
Soil near older buildings, airports or busy roads
Drinking water from lead pipes, faucets and plumbing fixtures
Toys, jewelry, antiques and collectible items
Certain foods, cosmetics and traditional medicines imported from other countries
Parents working in jobs or doing hobbies that involve working with lead-based products that they may bring home
On the food front, Calello stresses the importance of eating a varied diet — for both children and adults. "At this point, it's mostly about avoiding recalled foods and trying to vary your diet," she says. "If one particular food has a small amount of heavy metals, eating a lot of that one food can give you a lot of that metal."
Wellness, parenting, body image and more: Get to know the who behind the hoo with Yahoo Life's newsletter. Sign up here.