Aluminum additives used in vaccines are not linked to serious medical problems or long-term conditions in children, according to a report published today in The BMJ. In particular, researchers found no increased risk of asthma, autism, or autoimmune conditions such as type 1 diabetes.
The analysis, which included 59 studies conducted over many years, adds to a large body of research finding no ties between aluminum in childhood vaccines and serious health problems, including a 24-year study of more than 1.2 million Danish children published last year in the Annals of Internal Medicine.
“The evidence shows that vaccines containing aluminum are safe,” said Joseline Zafack, MD, PhD, MPH, senior author of the study and an epidemiologist at the Centre for Immunization Surveillance and Programs at the Public Health Agency of Canada.
The researchers found only one, benign medical condition potentially related to certain aluminum-containing vaccines: small skin nodules that go away on their own. Fewer than 1% of people given vaccines that prevent diphtheria, tetanus, and pertussis (DTaP) develop these nodules.
Vaccine makers have safely used tiny amounts of aluminum in vaccines for 100 years as a way to generate a better immune response. By boosting the immune system’s response, aluminum allows people to get strong protection from disease with a smaller quantity of vaccine and fewer doses.
Aluminum is used in routinely recommended childhood vaccines such as those that prevent hepatitis A, hepatitis B, diphteria-tetanus-pertussis, Haemophilus influenzae type b, human papillomavirus (HPV), meningococcus B and ABCWY, and pneumococcus.
A review of all available evidence
One strength of the new report is that it considers the totality of the evidence, not just one study, Zafack said.
Individual studies can be flawed or biased. Anti-vaccine activists and others who spread misinformation often cherry-pick single studies that confirm their opinions, holding them up as proof of vaccine injuries even after the research is retracted or discredited, said Peter Hotez, MD, co-director Texas Children’s Hospital Center for Vaccine Development, who was not involved in the new report.
The evidence shows that vaccines containing aluminum are safe.
The report is a systematic review, a type of analysis that collects all available evidence, assesses its quality, then synthesizes the results. These types of reviews give more weight to rigorous, well-done studies than to ones with weaker designs. They consider a specific, predefined question, such as “Does aluminum in vaccines cause harm?”
Especially important, systematic reviews explain their process very clearly, so that other researchers using the same methods can get the same results.
“People should not be drawing conclusions about one study that is presented in the media,” Zafack said. “We should review all of the evidence that’s available and account for the quality of the evidence in order to draw conclusions.”
Aluminum-containing vaccines under attack
Anti-vaccine activists, including Health and Human Services Secretary Robert F. Kennedy Jr., have attacked the use of aluminum in vaccines for years.
Kennedy, an attorney who has made millions of dollars working with a law firm suing a vaccine manufacturer, last year called for the Annals of Internal Medicine to retract the 2025 Danish study that found no link between aluminum in vaccines and autism. The journal’s editors refused.
There’s no reason to suspect aluminum as a cause of autism, Hotez said.
“This is what they do,” Hotez said. “It’s just made up.”
Dozens of studies have consistently found no link between vaccines and autism or other serious illnesses. But vaccines have saved more than 150 million lives over the past 50 years, according to the World Health Organization.
In spite of that research, anti-vaccine activists are constantly finding new reasons to oppose vaccination, Hotez said, whether it’s aluminum or some other ingredient.
When science shows that anti-vaccine arguments have no merit, and that a vaccine ingredient is safe, activists move on to another reason to attack vaccines, Hotez said.
“It’s a game of Whack-A-Mole,” he said.
There’s no escaping aluminum
Humans are constantly exposed to aluminum, not just in vaccines, but from pots, pans, soda cans, food, and hundreds of other products, according to Children’s Hospital of Philadelphia Vaccine Education Center. Aluminum, the third-most abundant mineral on the planet, is found in plants, water, soil, and air.
Adults ingest 7 to 9 milligrams of aluminum a day, and babies are exposed to much more aluminum from breast milk and formula than from vaccines.
“You have levels of aluminum in your bloodstream that are higher than anything you would get in a vaccine,” said Paul Offit, MD, director of the Vaccine Education Center.
Will the new report end questions about aluminum in vaccines?
“In a normal world, this would reassure people like Robert F. Kennedy Jr.,” said Offit, who was not involved in the report. “But he has a fixed, immutable, science-resistant belief.”
You have levels of aluminum in your bloodstream that are higher than anything you would get in a vaccine.
Hotez agreed the new report won’t satisfy anti-vaccine activists.
“The anti-vaccine lobby will try to find ways to poke holes in the paper, and even if they would accept that aluminum doesn’t cause autism, they will come up with something else,” Hotez said. “They will move the goal posts.”
But Offit said he hopes the new report will reassure parents that vaccines containing aluminum are safe.
“It’s perfectly reasonable to ask the question,” Offit said. “The good news is that there are systems in place that allow us to answer the question. We look to see whether there is any difference [in health] in children who receive vaccines that contain aluminum and those who don’t. But once the question has been answered, we have to accept that answer.”
